Next Article in Journal
Correlation of the Photocatalytic Activities of Cu, Ce and/or Pt-Modified Titania Particles with their Bulk and Surface Structures Studied by Reversed Double-Beam Photoacoustic Spectroscopy
Next Article in Special Issue
Perovskites in the Energy Grid and CO2 Conversion: Current Context and Future Directions
Previous Article in Journal
CO2 Methanation over Hydrotalcite-Derived Nickel/Ruthenium and Supported Ruthenium Catalysts
Previous Article in Special Issue
Ni Catalysts Based on Attapulgite for Hydrogen Production through the Glycerol Steam Reforming Reaction
 
 
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Hydrogen Production from Ammonia Borane over PtNi Alloy Nanoparticles Immobilized on Graphite Carbon Nitride

1
Key Laboratory of Metallurgical Emission Reduction & Resources Recycling, Ministry of Education, School of Metallurgical Engineering, Anhui University of Technology, Ma’anshan 243002, China
2
School of Chemistry and Chemical Engineering, Anhui Province Key Laboratory of Coal Clean Conversion and High Valued Utilization, Anhui University of Technology, Ma’anshan 243002, China
3
College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
4
Ahut Chemical Science & Technology Co., Ltd., Ma’anshan 243002, China
*
Author to whom correspondence should be addressed.
Catalysts 2019, 9(12), 1009; https://doi.org/10.3390/catal9121009
Submission received: 31 October 2019 / Revised: 26 November 2019 / Accepted: 29 November 2019 / Published: 1 December 2019
(This article belongs to the Special Issue Catalysis for Energy Production)

Abstract

:
Graphite carbon nitride (g-C3N4) supported PtNi alloy nanoparticles (NPs) were fabricated via a facile and simple impregnation and chemical reduction method and explored their catalytic performance towards hydrogen evolution from ammonia borane (AB) hydrolysis dehydrogenation. Interestingly, the resultant Pt0.5Ni0.5/g-C3N4 catalyst affords superior performance, including 100% conversion, 100% H2 selectivity, yielding the extraordinary initial total turnover frequency (TOF) of 250.8 molH2 min−1 (molPt)−1 for hydrogen evolution from AB at 10 °C, a relatively low activation energy of 38.09 kJ mol−1, and a remarkable reusability (at least 10 times), which surpass most of the noble metal heterogeneous catalysts. This notably improved activity is attributed to the charge interaction between PtNi NPs and g-C3N4 support. Especially, the nitrogen-containing functional groups on g-C3N4, serving as the anchoring sites for PtNi NPs, may be beneficial for becoming a uniform distribution and decreasing the particle size for the NPs. Our work not only provides a cost-effective route for constructing high-performance catalysts towards the hydrogen evolution of AB but also prompts the utilization of g-C3N4 in energy fields.

Graphical Abstract

1. Introduction

With the ever-growing consumption of fossil energy, accompanied with serious environmental issues, searching for green, sustainable, abundant, and alternative energy sources is of burgeoning urgency [1,2]. Hydrogen, as a clean energy source, has attracted significant research interest owing to its distinctive merits such as producing only water as a by-product and possessing more energy density than that of fossil fuels [3,4,5]. However, hydrogen, possessing the feature of low density, makes it difficult to liquefy and compress, thus hindering the large-scale applications [4,5,6]. Therefore, the exploration and seek for hydrogen storage materials with outstanding performance remains a challenging issue.
Tremendous efforts, in the past decades, have been made to explore and design hydrogen storage materials such as hydrazine, formic acid, and ammonia borane and so forth [7,8,9,10,11,12,13]. Among various hydrogen storage materials conducted, ammonia borane (AB), a white solid with excellent stability at room temperature and high hydrogen content (19.6 wt%), has aroused considerable interest as a promising hydrogen storage material [14,15]. There are two main approaches for AB to release hydrogen: (i) thermal dehydrogenation and (ii) hydrolytic dehydrogenation [14,15,16]. However, compared with thermal dehydrogenation, proceeding under high temperature, hydrolysis dehydrogenation process is easier to accomplish the industrial application under mild conditions [15,16,17]. With the aid of the suitable catalyst, 1 mol of AB can be controlled to release 3 mol of hydrogen under moderate conditions. The catalytic hydrolysis reaction can be described in detail as follows [18,19,20,21,22]:
N H 3 B H 3 ( aq ) + 2 H 2 O ( l ) C a t a l y s t N H 4 B O 2 ( aq ) + 3 H 2 ( g ) .
In recent years, a large number of supported metal catalysts including noble metal and non-noble metal, have been constructed for the hydrolysis of AB, among which Pt-based noble catalysts, as one of the most studied catalysts both in industrial and scientific fields, demonstrate more extraordinary catalytic performance than that of other metal catalysts for hydrolysis of AB [20,21,22,23,24,25,26,27]. However, the features of Pt with its high prices and limited reserves severely restrict its extensive utilization of Pt metal as the catalyst [27,28,29]. Currently, to actually reduce the utilization amount of Pt, assembling with the enhancement of catalysts, the fabrication of Pt alloy nanomaterials, especially coupling with the noble-free metals, such as Fe, Co, Ni, etc., has been identified to be an effective approach due to its structural and electronic effects [30,31,32,33]. Previous studies have revealed that Pt-M bimetallic catalysts could display higher catalytic activity than that of their single counterparts as well as lower cost [32,33,34,35,36]. For instance, Han et al. applied a chemical reduction route to synthesize amino modified SiO2 nanospheres supported CoPt-Co hybrid at 278 K, affording a turnover frequency (TOF) value of 25.59 molH2min−1molM−1, almost two-fold as high as that of unsupported Pt0.1Co0.9 nanoparticles (NPs) [37]. Xu et al. fabricated hierarchical nanoporous PtCu alloy nanoflowers by means of the two-step dealloying method with a maximum TOF value up to 108 molH2min−1molM−1 [38]. Lu et al. reported the synthesis of PtNi/NiO clusters coated by hollow silica using atomic sacrifice method, reaching a TOF of 1240.3 molH2min−1molPt−1 [39]. However, Pt-M NPs are readily tending to aggregate to form a bigger particle, resulting in a momentous decrease in the catalytic performance including activity, stability, and efficiency. Therefore, in order to obtain high catalytic performance for hydrolytic dehydrogenation of AB, considerable effort has been devoted to fabricate high efficiency catalysts involving many types of supporting materials.
It is noted that assembling alloy with appropriate supports, such as metal oxides, carbon nanotubes, mesoporous carbon nitride, graphene, etc., emerges as one of the novel encouraging approaches to further improve the catalytic activities and stability [39,40,41,42,43,44,45,46]. It is well known that the supporting materials play a critical role in enhancing its catalytic properties due to the synergistic effects between alloy and supports. Graphitic carbon nitride (g-C3N4), a promising two-dimensional non-metal material, is regarded as a promising candidate owing to its attractive electronic structure, high nitrogen content, excellent chemical and thermal stability, and environment friendliness [45,46,47,48]. Chen et al. constructed Au−Co nanoparticles (Au−Co@CN), displaying exceedingly good catalytic activity with a TOF value reaching 2897 mol H2molmetal −1h−1 at 298 K [49]. Fan et al. reported the in-situ construction of g-C3N4 supported Rh NPs, giving a very high TOF value of 969 mol H2molRh −1h−1 [50]. Encouraged by these achievements, the construction of PtNi alloy anchored into g-C3N4 for hydrogen production from the hydrolysis of AB is of paramount significance and has rarely been reported. Additionally, investigating the construction of bi-metal NPs in g-C3N4 as well as the exploration of the synergistic effect between them are also of outmost importance.
Hence, in this work, we focused on the construction of PtNi with different ratios immobilized on g-C3N4, preparing via the direct pyrolysis of melamine under nitrogen atmosphere [51,52], through a simple impregnation and co-reduction method under an ambient atmosphere. The resulting materials were evaluated as catalysts towards the hydrogen production from AB hydrolysis dehydrogenation under mild conditions. The influence of some parameters, such as metal concentration, catalyst concentration, AB concentration, and reaction temperature, on the catalytic performance of PtNi/g-C3N4 were conducted in detail. Especially, the Pt0.5Ni0.5/g-C3N4 demonstrates optimal catalytic performance for the hydrolysis of AB compared with the samples of other molar ratios of PtNi. Furthermore, the stability of the optimum catalyst was investigated as well.

2. Results and Discussion

The synthesis process of PtNi/g-C3N4 is schematically emerged in Scheme 1. Typically, g-C3N4 was prepared via a direct pyrolysis route employing melamine as precursor. Then, the Pt and Ni precursor with different contents immobilized on g-C3N4 was fabricated, using a simple impregnation and reduction process, where sodium borohydride is employed as a reducing agent, and then applied as catalysts towards hydrogen production of AB. The accurate composition of PtNi/g-C3N4 was analyzed by inductively coupled plasma atomic emission spectroscopy (ICP-AES), which were close to their desired contents (Table S1). Elemental analysis revealed that the composition of C, H, and N of g-C3N4 was 34.71 wt%, 1.89 wt%, and 61.47 wt%, respectively. As displayed in Table S1, Figure S1, the Brunner−Emmet−Teller (BET) specific areas of PtNi/g-C3N4 was around 10 m2/g, which was close to the values reported in the literature [51,52]. Figure 1 shows the XRD patterns of PtNi/g-C3N4 with different contents.
It is evident that a strong peak at 27.5° for all samples was attributed to the (200) plane of g-C3N4. For Ni/g-C3N4, other than the characteristic peak of g-C3N4, there were three peaks centered at 44.5°, 51.8°, and 76.4°, respectively, which could be ascribed to the (111), (200), and (220) planes of Ni (JCPDS no: 65-0380). For Pt/g-C3N4, three peaks at 39.8°, 46.2°, and 67.5° were assigned to the (111), (200), and (220) planes of Pt (JCPDS no: 65-2868). Furthermore, it was evident that a shift to a higher angle compared to that of the Pt (111) peak in Pt/g-C3N4, indicating that PtNi existed in the form of an alloy, which was consistent with the previous literatures yet reported [39,53,54,55]. The chemical structures of g-C3N4, Pt/g-C3N4, Ni/g-C3N4, and Pt0.5Ni0.5/g-C3N4 were further investigated by Fourier transform infrared (FTIR), as presented in Figure 2. A similar FT-IR spectra could be observed for all samples. An obvious absorption peak centered at 810 cm−1 for all samples was ascribed to the bending vibration of the s-triazine ring. A series of peaks detected in 1200–1600 cm−1 were identified as the stretching modes of aromatic CN heterocycles. In addition, the broad absorption ranging from 3000 to 3400 cm−1 was attributed to the stretching mode of O–H (adsorbed water molecules) and N–H (amino groups) [31,32,33,34,35,36,51,52].
To gain the valence state of Pt and Ni, X-ray photoelectron spectroscopy (XPS) analysis was employed for Pt0.5Ni0.5/g-C3N4, and the result is illustrated in Figure 3, which presents the characteristic peaks for Pt and Ni, thus implying the coexistence of both metals. The binding energy (BE) of C and N in Pt0.5Ni0.5/g-C3N4 were in accordance with the previous reported literatures about g-C3N4 (Figure S2) [50,51,52]. As given in Figure 3a, the BE observed at 852.5 and 869.9 eV were ascribed to the Ni 2p3/2 and Ni 2p1/2 of metallic Ni, respectively. The oxidized Ni centered at 858.1 and 876.5 eV were detected, which might likely attribute to the partial oxidation of Ni during the sample treatment route for the XPS measurements, as revealed before [56,57,58]. The BE of 71.4 and 74.6 eV in Figure 3b corresponded to the Pt 4f7/2 and Pt 4f5/2 of metallic Pt. In addition, there was a positive shift toward 0.1 eV for the BE of Pt in Pt0.5Ni0.5/g-C3N4 compared with that of pure Pt, while a negative shift with 0.4 eV could be observed for Ni in Pt0.5Ni0.5/g-C3N4 in comparison with that of pure Ni, thereby confirming the formation of the PtNi alloy, which was in good agreement with those of alloys previously reported [56,57,58,59,60,61].
To further explore the morphology and microstructure of the Pt0.5Ni0.5/g-C3N4 catalyst, we conducted TEM, high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), and energy-dispersive X-ray spectroscopic (EDS) measurements, as depicted in Figure 4a–i. The TEM images of Ni/g-C3N4 revealed that almost all the nanoparticles were uniformly dispersed into the surface of g-C3N4 with an average size of 4.3 nm (Figure S3a,b). Furthermore, for Pt/g-C3N4, there were many homogeneous distribution of nanoparticles with their size ranging from 3.6 to 6.0 nm, as depicted in Figure S3d,e. However, TEM images revealed that the PtNi nanoparticles in Pt0.5Ni0.5/g-C3N4 catalyst had a uniform diameter distribution with a mean diameter of 3.2 nm and were homogeneously dispersed on the surface of g-C3N4 (Figure 4a–c), which might be due to the alloy effect. Figure 4b presents that the d-spacing of the particle was 0.211 nm, which differed from the (111) plane of Pt (0.227 nm; Figure S3f) and Ni (0.204 nm; Figure S3c), further revealing that Pt0.5Ni0.5 was in the form of the alloy state [54,55,56,58,59,60,61]. The energy dispersive X-ray (EDX) result (Figure S4) further verified the coexistence of Pt and Ni in the Pt0.5Ni0.5/g-C3N4. A representative high-angle annular dark-field scanning TEM (HAADF-STEM) image confirmed the homogeneous distribution of Pt and Ni elements on the g-C3N4 catalyst surface at the same position (Figure 4d–i), which confirmed again the formation of a PtNi alloy.
Figure 5a presents the hydrogen release from AB catalyzed by PtxNi1-x/g-C3N4 catalyst with different components. Among all the PtxNi1-x/g-C3N4 conducted, Pt0.5Ni0.5/g-C3N4 revealed optimum catalytic performance towards the dehydrogenation of AB in comparison with that of another molar ratio of PtxNi1-x/g-C3N4. The hydrogen production from AB hydrolysis dehydrogenation over Pt0.5Ni0.5/g-C3N4 could be completed within only 1.5 min, giving a TOF value of 250.8 molH2 min−1 (molPt)−1 (Figure 5b), which was the highest as compared with other as-prepared PtNi alloy catalysts, as well higher than most reported Pt-based or other noble metal-based catalysts towards the hydrogen evolution of AB hydrolysis dehydrogenation as displayed in Table 1 [38,40,62,63,64,65,66,67,68]. The results showed that the platinum coupling with nickel could significantly improve the hydrolytic activity of AB. The superior catalytic performance of the Pt0.5Ni0.5/g-C3N4 can be ascribed to the synergetic effect between Pt and Ni atoms as well as the enhanced interaction between PtNi NPs and g-C3N4.
Given that Pt0.5Ni0.5/g-C3N4 demonstrated the best catalytic performance towards the dehydrogenation of AB in this work, Pt0.5Ni0.5/g-C3N4, as the representative, was selected to further explore its dehydrogenation kinetics. As illustrated in Figure 6a, the catalyst concentrations-dependent test of Pt0.5Ni0.5 NPs was investigated at 10 °C by modifying the catalyst concentration ranging from 6.25 to 25 mM. The hydrogen generation rate demonstrated an obvious upward tendency with the increasing of catalyst concentrations. The relation between logarithmic plots of dehydrogenation rate and catalyst concentrations is illustrated in Figure 6b. The slope of straight line was estimated to be 1.08, implying that the dehydrogenation reaction was first-order in terms of the catalyst concentration. Furthermore, to explore the influence of AB concentration on the dehydrogenation of AB, a series of experiments with different concentrations of AB were performed, where the AB concentrations were modulated from 250 to 1000 mM, as shown in Figure 6a, and Pt0.5Ni0.5/g-C3N4 NPs was kept at 0.100 g. Figure 7a shows corresponding hydrogen amount versus time. As the concentration of AB increased, the dehydrogenation reaction time increased clearly from 0.8 to 1.5 min. Figure 7b displays logarithmic plots of dehydrogenation rate versus AB concentrations, where the line slope was 0.05, suggesting that the dehydrogenation reaction of AB presents zero-order regarding the catalyst concentrations.
To explore the influence of temperature, the AB concentration was maintained at 1000 mM and the Pt0.5Ni0.5/g-C3N4 was kept at 0.100 g. Plot of the molar ratio of H2/AB versus time for hydrogen evolution from AB catalyzed by Pt0.5Ni0.5/g-C3N4 catalyst at different temperatures are presented in Figure 8a. As the reaction temperature changed from −5 to 10 °C, the dehydrogenation rate significantly increased. According to the slop of the straight line in Figure 8b, the activation energy was estimated to be 38.09 kJ/mol, which was lower than most of the reported Ea values of many different Pt-based and some other catalysts [62,63,64,65,66,67,68].
Combining the XRD, FT-IR, XPS, and TEM, a possible mechanism for the hydrogen evolution from ammonia borane catalyzed by Pt0.5Ni0.5/g-C3N4 can be proposed. The obtained results endow persuasive and obvious evidence regarding the synergistic effects between Pt and Ni in the Pt0.5Ni0.5 NPs and the synergistic electronic effects between Pt0.5Ni0.5 nanoparticles and g-C3N4, which could efficiently activate the B–N bonds in AB, thereby lowering the reaction energy barrier and prompting hydrogen evolution, as verified by Table S1. As shown in Scheme 2, firstly, both H2O and AB were adsorbed on the surface of the catalyst, and then, the B–H bond of AB was broken to form H3NBH2−OH by attacking BH3* group in H3NBH3 using OH*, the OH* further attacked other B–H to dissociate hydrogen atoms. At last, the dissociated hydrogen atoms in the surface of the catalysts could combine to release hydrogen gas [69,70,71,72]. In addition, the active energy for the dehydrogenation catalyzed by Pt0.5Ni0.5/g-C3N4 was calculated to as low as 38.09 kJ mol−1 and its kinetics were also obviously improved.
The stability, as a significant issue for the large-scale application of one catalyst, of the Pt0.5Ni0.5/g-C3N4 in the hydrolytic dehydrogenation of AB was studied and displayed in Figure 9a. However, after 10 successive cycles, the hydrolysis of AB can also be completed within 3 min, generating a TOF value of 136.8 molH2 min−1 (molPt)−1, which is only 55% of its initial catalytic activity. To further explore the reason for the decreased dehydrogenation performance, the morphology of Pt0.5Ni0.5/g-C3N4 after the cycle test was characterized by TEM, as presented in Figure 9b. The slight aggregation can be observed, which may be attributed to the activity decay of Pt0.5Ni0.5/g-C3N4.

3. Materials and Methods

3.1. Materials and Chemicals

Ammonia borane (NH3BH3, AB, ≥90%,) and melamine (C3H6N6, ≥99%) were obtained from Aldrich (Shanghai, China). Chloroplatinic acid (H2PtCl6) was supplied by Nanjing Chemical Reagent Co., Ltd. (Nanjing, China). Nickel(II) chloride hexahydrate (NiCl2·6H2O, AR), sodium hydroxide (NaOH, ≥96.0%), and sodium borohydride (NaBH4, ≥98%) were purchased from Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China). All chemicals were purchased and used without further treatment.

3.2. Synthesis of g-C3N4

Pure g-C3N4 was prepared by the direct pyrolysis of melamine, as reported by previous literatures [51,52]. Specifically, 2.00 g of melamine, placed into an alumina crucible with a cover, was annealed at 520 °C in a muffle furnace for 2 h at a ramp rate of 3 °C/min. After cooling to room temperature naturally, the resulting yellow-colored material was g-C3N4.

3.3. Synthesis of PtNi/g-C3N4

PtNi/g-C3N4 was fabricated via a simple and facile impregnation and chemical reduction method. In a typical procedure, for Pt0.5Ni0.5/g-C3N4, 200 mg of g-C3N4 and 0.4 mmol of metal precursors (0.2 mmol of H2PtCl6 and 0.2 mmol of NiCl2) were firstly mixed under ultrasonic for 30 min, and then the mixture was continuously stirred for 24 h at room temperature. After that, a mixture solution containing 0.08 g of NaBH4 was added the above-mentioned solution at −3 °C, and then stirring for 5 h. Finally, the resulting mixture was centrifuged and dried at 80 °C in a vacuum oven. The obtained powder was denoted as Pt0.5Ni0.5/g-C3N4. The g-C3N4 supported Pt/Ni with other molar ratios could be labeled as PtxNi1-x/g-C3N4 (x = 0, 0.2, 0.4, 0.6, 0.8, and 1).

3.4. Characterization

The crystal structure of the catalysts was recorded at a scanning rate of 4 °min−1 using a X-ray diffraction (XRD, Bruker, Berlin, Germany) D8-Advance, Cu Ka radiation source (λ = 0.154178 nm)). The Fourier transformed infrared spectra (FTIR) was investigated by a Tensor 27 spectrometer (Bruker, Berlin, Germany). The metal composition of the catalysts was conducted by employing inductively coupled plasma-atomic emission spectrometer (ICP-AES, Thermo iCAP6300, Washington, USA). The specific surface area was measured using Micromeritics ASAP2020 (Washington, USA) according to adsorption/desorption nitrogen isotherms. The electronic states of the surface of the as-obtained catalyst were measured by X-ray photoelectron spectroscopy (XPS, Thermo scientific Escalab 250Xi, Washington, USA). The morphologies and sizes of the catalysts were obtained using a transmission electron microscope (TEM, JEOL JEM 2100F, Freising, Germany) equipped with an energy dispersive X-ray detector (EDX, Freising, Germany) at a working voltage of 200 kV. The composition of the generated gas was evaluated through a Hiden QIC-20 quadruple mass spectrometer (Warrington, UK) using Ar as carrying gas.

3.5. Catalytic Activity Measurement

In a typical experiment, 0.1 g of the as-obtained PtNi/g-C3N4 was dispersed into 2 mL water in a two-necked round-bottom flask. A solution containing 2 mL of AB (2 M) was injected through one neck with a syringe under stirring, and the other was connected with a gas burette to estimate the volume of gas. Upon the injection of AB aqueous solution, the amount of H2 production was estimated via water-displacement approach by measuring the volume of drained water. The reaction time was recorded as the first bubble appeared. The reaction was over when there was no gas released. The reaction was carried out under designed temperature, controlling by cryogenic bath. The turnover frequency (TOF, molH2 molPt−1 min−1) was calculated according to the linear relationship between volume and time in AB hydrolysis.
In order to explore the influence of catalysts concentration, AB concentration over the dehydrogenation of AB, AB hydrolysis for the Pt0.5Ni0.5/g-C3N4 was evaluated in the same way as described above, except that the parameters, such as catalysts concentration, AB concentration, were changed, respectively. In addition, to acquire the activation energy (Ea) value of the hydrogen production of AB over Pt0.5Ni0.5/g-C3N4 catalyst, the hydrolysis of AB was conducted at a series of temperatures including −5 °C, 0 °C, 5 °C, and 10 °C.

3.6. Stability Tests

The catalyst was recovered by centrifugation, washed with ethanol and water, and dried in an oven after the completion of the dehydrogenation reaction. Then the recovered catalyst was set into a two-necked round-bottom flask according to the above-mentioned dehydrogenation procedure for stability tests. A similar operation was repeated ten times.

4. Conclusions

In summary, we reported a simple and facile impregnation and chemical reduction approach to synthesize PtNi/g-C3N4 nanoparticles as a catalyst for boosting the hydrogen generation of AB. Among the PtxNi1-x/g-C3N4 catalysts, the resultant Pt0.5Ni0.5/g-C3N4 catalyst demonstrated outstanding performance, including 100% conversion, 100% H2 selectivity, yielding the extraordinary initial total turnover frequency (TOF) of 250.8 molH2 min−1 (molPt)−1 for hydrogen production from AB at 10 °C, a relatively low activation energy of 38.09 kJ mol−1, and a remarkable reusability (at least 10 times), which outperformed most of the noble metal heterogeneous catalysts. This notably improved activity was attributed to the charge interaction between PtNi NPs and g-C3N4 support. Especially, the nitrogen-containing functional groups on g-C3N4, serving as the anchoring sites for PtNi NPs, might be beneficial for forming a uniform distribution and decreasing the particle size for the NPs. Moreover, the fabrication of g-C3N4-based catalysts might prompt the utilization of g-C3N4 in energy fields.

Supplementary Materials

The following are available online at https://www.mdpi.com/2073-4344/9/12/1009/s1, Figure S1: N2 adsorption-desorption isotherms of Pt0.5Ni0.5/g-C3N4, Figure S2: XPS spectra for Pt0.5Ni0.5/g-C3N4 showing C 1s, N 1s, Figure S3: (a) TEM images of Ni/g-C3N4, (b) amplified HRTEM image of Ni/g-C3N4, (c) Particle size distribution of Ni/g-C3N4, (d) TEM images of Pt/g-C3N4, (e) amplified HRTEM image of Pt/g-C3N4, (f) Particle size distribution of Pt/g-C3N4, Figure S4: SEM−energy-dispersive X-ray spectroscopic (EDS) spectrum of Pt0.5Ni0.5/g-C3N4, Table S1: ICP-AES results of PtNi/g-C3N4 catalysts.

Author Contributions

Data curation, M.Z.; Writing—original draft, X.X.; Investigation, Y.W.; Formal analysis, Y.A.; Funding acquisition, L.X.; Supervision, Writing—review and editing, C.W.

Funding

This work was financially supported by Anhui Provincial Natural Science Foundation (1608085QF156, 1908085QB68), the Natural Science Foundation of the Anhui Higher Education Institutions of China (KJ2019A0072), Foundation of Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology (Grant No. ZJKL-ACEMT-1802), China Postdoctoral Science Foundation (2019M662060), Research Fund for Young Teachers of Anhui University of Technology (QZ201610) and National Natural Science Foundation of China (21376005).

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Graetz, J. New approaches to hydrogen storage. Chem. Soc. Rev. 2009, 38, 73–82. [Google Scholar] [CrossRef] [PubMed]
  2. Yu, X.B.; Tang, Z.W.; Sun, D.L.; Ouyang, L.Z.; Zhu, M. Recent advances and remaining challenges of nanostructured materials for hydrogen storage applications. Prog. Mater. Sci. 2017, 88, 1–48. [Google Scholar] [CrossRef]
  3. He, T.; Pachfule, P.; Wu, H.; Xu, Q.; Chen, P. Hydrogen carriers. Nat. Rev. Mater. 2016, 1, 16059. [Google Scholar] [CrossRef]
  4. Liu, T.; Wang, Q.T.; Yuan, J.Z.; Zhao, X.; Gao, G.H. Highly Dispersed Bimetallic Nanoparticles Supported on Titanium Carbides for Remarkable Hydrogen Release from Hydrous Hydrazine. ChemCatChem 2018, 10, 2200–2204. [Google Scholar] [CrossRef]
  5. Yadav, M.; Xu, Q. Liquid-phase chemical hydrogen storage materials. Energy Environ. Sci. 2012, 5, 9698–9725. [Google Scholar] [CrossRef]
  6. Schlapbach, L.; Züttel, A. Hydrogen-storage materials for mobile applications. Mater. Sustain. Energy 2011, 265–270. [Google Scholar]
  7. Yao, F.; Li, X.; Wan, C.; Xu, L.X.; An, Y.; Ye, M.F.; Lei, Z. Highly efficient hydrogen release from formic acid using a graphitic carbon nitride-supported AgPd nanoparticle catalyst. Appl. Surf. Sci. 2017, 426, 605–611. [Google Scholar] [CrossRef]
  8. Staubitz, A.; Robertson, A.P.M.; Manners, I. Ammonia-Borane and related compounds as dihydrogen sources. Chem. Rev. 2010, 110, 4079–4124. [Google Scholar] [CrossRef]
  9. Zhou, Y.-H.; Wang, S.Q.; Zhang, Z.Y.; Williams, N.; Cheng, Y.; Gu, J. Hollow Nickel–Cobalt Layered Double Hydroxide Supported Palladium Catalysts with Superior Hydrogen Evolution Activity for Hydrolysis of Ammonia Borane. ChemCatChem 2018, 10, 3206–3213. [Google Scholar] [CrossRef]
  10. Huang, X.Y.; Wang, A.J.; Zhang, L.; Fang, K.M.; Wu, L.J.; Feng, J.J. Melamine-assisted solvothermal synthesis of PtNi nanodentrites as highly efficient and durable electrocatalyst for hydrogen evolution reaction. J. Colloid Interface Sci. 2018, 531, 578–584. [Google Scholar] [CrossRef]
  11. Wan, C.; Yao, F.; Li, X.; Hu, K.; Ye, M.F.; Xu, L.X.; An, Y. Bimetallic AgPd Nanoparticles Immobilized on Amine-Functionalized SBA-15 as Efficient Catalysts for Hydrogen Generation from Formic Acid. ChemistrySelect 2016, 1, 6907–6913. [Google Scholar] [CrossRef]
  12. Chen, J.M.; Lu, Z.H.; Yao, Q.L.; Feng, G.; Luo, Y. Complete dehydrogenation of N2H4BH3 with Ni-MCr2O3 (M = Pt, Rh, and Ir) hybrid nanoparticles. J. Mater. Chem. A 2018, 6, 20746–20752. [Google Scholar] [CrossRef]
  13. Zhang, L.T.; Cai, Z.L.; Yao, Z.D.; Ji, L.; Sun, Z.; Yan, N.H.; Zhang, B.Y.; Xiao, B.B.; Du, J.; Zhu, X.Q.; et al. A striking catalytic effect of facile synthesized ZrMn2 nanoparticles on the de/rehydrogenation properties of MgH2. J. Mater. Chem. A 2019, 7, 5626–5634. [Google Scholar] [CrossRef]
  14. Akbayrak, S.; Özçifçi, Z.; Tabak, A. Regular Article Noble metal nanoparticles supported on activated carbon: Highly recyclable catalysts in hydrogen generation from the hydrolysis of ammonia borane. J. Colloid Interface Sci. 2019, 546, 324–332. [Google Scholar] [CrossRef] [PubMed]
  15. Qu, X.P.; Jiang, R.; Li, Q.; Zeng, F.N.; Zheng, X.; Xu, Z.M.; Chen, C.H.; Peng, J. The hydrolysis of ammonia borane catalyzed by NiCoP/OPC-300 nanocatalysts: High selectivity and efficiency, and mechanism. Green Chem. 2019, 21, 850–860. [Google Scholar] [CrossRef]
  16. Li, J.; Li, F.; Liao, J.; Liu, Q.; Li, H. Cu0.4Co0.6MoO4 Nanorods Supported on Graphitic Carbon Nitride as a Highly Active Catalyst for the Hydrolytic Dehydrogenation of Ammonia Borane. Catalysts 2019, 9, 714. [Google Scholar] [CrossRef]
  17. Torres, D.A.; Garcia, M.N.; Mori, K.; Kuwahara, Y.; Yamashita, H. Nitrogen-doped carbon materials as a promising platform toward the efficient catalysis for hydrogen generation. Appl. Catal. A Gen. 2019, 571, 25–41. [Google Scholar] [CrossRef]
  18. Bandaru, S.; English, N.J.; Phillips, A.D.; MacElroy, J.M.D. Exploring Promising Catalysts for Chemical Hydrogen Storage in Ammonia Borane: A Density Functional Theory Study. Catalysts 2017, 7, 140. [Google Scholar] [CrossRef]
  19. Wei, Z.H.; Liu, Y.; Peng, Z.K.; Song, H.Q.; Liu, Z.Y.; Liu, B.Z.; Li, B.J.; Yang, B.; Lu, S.Y. Cobalt-Ruthenium Nanoalloys Parceled in Porous Nitrogen-Doped Graphene as Highly Efficient Difunctional Catalysts for Hydrogen Evolution Reaction and Hydrolysis of Ammonia Borane. ACS Sustain. Chem. Eng. 2019, 7, 7014–7023. [Google Scholar] [CrossRef]
  20. Chen, W.Y.; Wang, Z.J.; Duan, X.Z.; Qian, G.; Chen, D.; Zhou, X.G. Structural and kinetic insights into Pt/CNT catalysts during hydrogen generation from ammonia borane. Chem. Eng. Sci. 2018, 192, 1242–1251. [Google Scholar] [CrossRef]
  21. Xu, C.L.; Wang, H.; Wang, Q.; Wang, Y.; Zhang, Y.; Fan, G.Y. Ruthenium coordinated with triphenylphosphine-hyper-crosslinked polymer: An efficient catalyst for hydrogen evolution reaction and hydrolysis of ammonia borane. Appl. Surf. Sci. 2019, 466, 193–201. [Google Scholar] [CrossRef]
  22. Zhang, J.K.; Chen, W.Y.; Ge, H.B.; Chen, C.Q.; Yan, W.J.; Gao, Z.; Gan, J.; Zhang, B.Y.; Duan, X.Z.; Qin, Y. Synergistic effects in atomic-layer-deposited PtCox/CNTs catalysts enhancing hydrolytic dehydrogenation of ammonia borane. Appl. Catal. B 2018, 235, 256–263. [Google Scholar] [CrossRef]
  23. Liu, Y.; Zhang, J.; Guan, H.J.; Zhao, Y.F.; Yang, J.H.; Zhang, B. Preparation of bimetallic Cu-Co nanocatalysts on poly (diallyldimethylammonium chloride) functionalized halloysite nanotubes for hydrolytic dehydrogenation of ammonia borane. Appl. Surf. Sci. 2018, 427, 106–113. [Google Scholar] [CrossRef]
  24. Hou, C.C.; Li, Q.; Wang, C.J.; Peng, C.Y.; Chen, Q.Q.; Ye, H.F.; Fu, W.F.; Che, C.M.; López, N.; Chen, Y. Ternary Ni–Co–P nanoparticles as noble-metal-free catalysts to boost the hydrolytic dehydrogenation of ammonia-borane. Energy Environ. Sci. 2017, 10, 1770–1776. [Google Scholar] [CrossRef]
  25. Zhao, W.; Wang, R.Y.; Wang, Y.; Feng, J.W.; Li, C.C.; Chen, G.Z. Effect of LDH composition on the catalytic activity of Ru/LDH for the hydrolytic dehydrogenation of ammonia borane. Int. J. Hydrogen Energy 2019, 44, 14820–14830. [Google Scholar] [CrossRef]
  26. Özhava, D.; Özkar, S. Nanoceria supported rhodium (0) nanoparticles as catalyst for hydrogen generation from methanolysis of ammonia borane. Appl. Catal. B 2018, 237, 1012–1020. [Google Scholar] [CrossRef]
  27. Akbayrak, S.; Özkar, S. Ammonia borane as hydrogen storage materials. Int. J. Hydrogen Energy 2018, 43, 18592–18606. [Google Scholar] [CrossRef]
  28. Wen, M.; Wu, Q.N.; Peng, J.; Wu, Q.S.; Wang, C.X. Fabrication of Pt-loaded NiCo nanochains with superior catalytic dehydrogenation activity. J. Colloid Interface Sci. 2014, 416, 220–226. [Google Scholar] [CrossRef]
  29. Wan, C.; Cheng, D.G.; Chen, F.Q.; Zhan, X.L. Fabrication of CeO2 nanotube supported Pt catalyst encapsulated with silica for high and stable performance. Chem. Commun. 2015, 51, 9785–9788. [Google Scholar] [CrossRef]
  30. Wang, S.; Zhang, D.; Ma, Y.Y.; Zhang, H.; Gao, J.; Nie, Y.T.; Sun, X.H. Aqueous solution synthesis of Pt-M (M = Fe, Co, Ni) bimetallic nanoparticles and their catalysis for the hydrolytic dehydrogenation of ammonia borane. ACS Appl. Mater. Interfaces 2014, 6, 12429–12435. [Google Scholar] [CrossRef]
  31. Du, Y.S.; Su, J.; Luo, W.; Cheng, G.Z. Graphene-Supported Nickel−Platinum Nanoparticles as Efficient Catalyst for Hydrogen Generation from Hydrous Hydrazine at Room Temperature. ACS Appl. Mater. Interfaces 2015, 7, 1031–1034. [Google Scholar] [CrossRef] [PubMed]
  32. Zhao, B.H.; Feng, K.; Wang, Y.; Lv, X.X.; Zheng, H.C.; Ma, Y.Y.; Yan, W.S.; Sun, X.H.; Zhong, J. PtxNi10−xO nanoparticles supported on N-doped graphene oxide with a synergetic effect for highly efficient hydrolysis of ammonia borane. Catal. Sci. Technol. 2017, 7, 5135–5142. [Google Scholar] [CrossRef]
  33. Xia, Y.; Ye, J.R.; Cheng, D.G.; Chen, F.Q.; Zhan, X.L. Identification of a flattened Pd–Ce oxide cluster as a highly efficient catalyst for low-temperature CO oxidation. Catal. Sci. Technol. 2018, 8, 5137–5147. [Google Scholar] [CrossRef]
  34. Huang, X.Y.; Zhu, X.Y.; Zhang, X.F.; Zhang, L.; Feng, J.J.; Wang, A.J. Simple solvothermal synthesis of uniform Pt66Ni34 nanoflowers as advanced electrocatalyst to significantly boost the catalytic activity and durability of hydrogen evolution reaction. Electrochim. Acta 2018, 271, 397–405. [Google Scholar] [CrossRef]
  35. Chen, X.L.; Zhang, H.X.; Huang, X.Y.; Feng, J.J.; Han, D.M.; Zhang, L.; Chen, J.R.; Wang, A.J. Facile solvothermal fabrication of Pt47Ni53 nanopolyhedrons for greatly boosting electrocatalytic performances for oxygen reduction and hydrogen evolution. J. Colloid Interface Sci. 2018, 525, 260–268. [Google Scholar] [CrossRef]
  36. Karaca, T.; Sevim, M.; Metin, Ö. Facile Synthesis of Monodisperse Copper–Platinum Alloy Nanoparticles and Their Superb Catalysis in the Hydrolytic Dehydrogenation of Ammonia Borane and Hydrazine Borane. ChemCatChem 2017, 9, 4185–4190. [Google Scholar] [CrossRef]
  37. Zhang, H.M.; Ke, D.D.; Cheng, L.N.; Feng, X.L.; Hou, X.W.; Wang, J.; Lia, Y.; Han, S.M. CoPt-Co hybrid supported on amino modified SiO2 nanospheres as a high performance catalyst for hydrogen generation from ammonia borane. Sci. Mater. 2019, 29, 1–9. [Google Scholar] [CrossRef]
  38. Zhou, Q.X.; Qi, L.; Yang, H.X.; Xu, C.X. Hierarchical nanoporous platinum–copper alloy nanoflowers as highly active catalysts for the hydrolytic dehydrogenation of ammonia borane. J. Colloid Interface Sci. 2018, 513, 258–265. [Google Scholar] [CrossRef]
  39. Ge, Y.Z.; Ye, W.Y.; Shah, Z.H.; Lin, X.J.; Lu, R.W.; Zhang, S.F. PtNi/NiO Clusters Coated by Hollow Sillica: Novel Design for Highly Efficient Hydrogen Production from Ammonia–Borane. ACS Appl. Mater. Interfaces 2017, 9, 3749–3756. [Google Scholar] [CrossRef]
  40. Zhou, Q.X.; Xu, C.X. Nanoporous PtCo/Co3O4 composites with high catalytic activities toward hydrolytic dehydrogenation of ammonia borane. J. Colloid Interface Sci. 2017, 508, 542–550. [Google Scholar] [CrossRef]
  41. Chen, W.Y.; Ji, J.; Feng, X.; Duan, X.Z.; Qian, G.; Li, P.; Zhou, X.G.; Chen, D.; Yuan, W.K. Mechanistic Insight into Size-Dependent Activity and Durability in Pt/CNT Catalyzed Hydrolytic Dehydrogenation of Ammonia Borane. J. Am. Chem. Soc. 2014, 136, 16736–16739. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  42. Kamegawa, T.; Nakaue, T. Complete hydrogen release from aqueous ammonia-borane over a platinum-loaded titanium dioxide photocatalyst. Chem. Commun. 2015, 51, 16802–16805. [Google Scholar] [CrossRef] [PubMed]
  43. Zhu, M.Y.; Xu, L.X.; Du, L.; An, Y.; Wan, C. Palladium supported on carbon nanotubes as a high-performance catalyst for the dehydrogenation of dodecahydro-N-ethylcarbazole. Catalysts 2018, 8, 638. [Google Scholar] [CrossRef] [Green Version]
  44. Ke, D.D.; Wang, J.; Zhang, H.M.; Li, Y.; Zhang, L.; Zhao, X.; Han, S.M. Fabrication of Pt-Co NPs supported on nanoporous graphene as high-efficient catalyst for hydrolytic dehydrogenation of ammonia borane. Int. J. Hydrogen Energy 2017, 42, 26617–26625. [Google Scholar] [CrossRef]
  45. Wang, C.L.; Tuninetti, J.; Wang, Z.; Zhang, C.; Ciganda, R.; Salmon, L.; Moya, S.; Ruiz, J.; Astruc, D. Hydrolysis of Ammonia-Borane over Ni/ZIF-8 Nanocatalyst: High Efficiency, Mechanism, and Controlled Hydrogen Release. J. Am. Chem. Soc. 2017, 139, 11610–11615. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  46. Wang, W.; Lu, Z.H.; Luo, Y.; Zou, A.H.; Yao, Q.L.; Chen, X.S. Mesoporous Carbon Nitride Supported Pd and Pd-Ni Nanoparticles as Highly Efficient Catalyst for Catalytic Hydrolysis of NH3BH3. ChemCatChem 2018, 10, 1620–1626. [Google Scholar] [CrossRef]
  47. Han, C.H.; Meng, P.; Waclawik, E.R.; Zhang, C.; Li, X.H.; Yang, H.Q.; Antonietti, M.; Xu, J.S. Palladium/Graphitic Carbon Nitride (g-C3N4) Stabilized Emulsion Microreactor as a Store for Hydrogen from Ammonia Borane for Use in Alkene Hydrogenation. Angew. Chem. Int. Ed. 2018, 57, 14857–14861. [Google Scholar] [CrossRef]
  48. Ong, W.J.; Tan, L.L.; Ng, Y.H.; Yong, S.T.; Chai, S.P. Graphitic Carbon Nitride (g-C3N4)-Based Photocatalysts for Artificial Photosynthesis and Environmental Remediation: Are We a Step Closer To Achieving Sustainability? Chem. Rev. 2016, 116, 7159–7329. [Google Scholar] [CrossRef]
  49. Guo, L.T.; Cai, Y.Y.; Ge, J.M.; Zhang, Y.N.; Gong, L.H.; Li, X.H.; Wang, K.X.; Ren, Q.Z.; Su, J.; Chen, J.S. Multifunctional Au−Co@CN Nanocatalyst for Highly Efficient Hydrolysis of Ammonia Borane. ACS Catal. 2015, 5, 388–392. [Google Scholar] [CrossRef]
  50. Lu, R.; Hu, M.; Xu, C.L.; Wang, Y.; Zhang, Y.; Xu, B.; Gao, D.J.; Bi, J.; Fan, G.Y. Hydrogen evolution from hydrolysis of ammonia borane catalyzed by Rh/g-C3N4 under mild conditions. Int. J. Hydrogen Energy 2018, 43, 7038–7045. [Google Scholar] [CrossRef]
  51. Wang, X.C.; Blechert, S.; Antonietti, M. Polymeric Graphitic Carbon Nitride for Heterogeneous Photocatalysis. ACS Catal. 2012, 2, 1596–1606. [Google Scholar] [CrossRef]
  52. Xu, L.X.; Liu, N.; Hong, B.; Cui, P.; Cheng, D.G.; Chen, F.Q.; An, Y.; Wan, C. Nickel–platinum nanoparticles immobilized on graphitic carbon nitride as highly efficient catalyst for hydrogen release from hydrous hydrazine. RSC Adv. 2016, 6, 31687–31691. [Google Scholar] [CrossRef]
  53. Fu, F.Y.; Wang, C.L.; Wang, Q.; Martinez-Villacorta, A.M. Highly Selective and Sharp Volcano-type Synergistic Ni2Pt@ZIF-8-Catalyzed Hydrogen Evolution from Ammonia Borane Hydrolysis. J. Am. Chem. Soc. 2018, 140, 10034–10042. [Google Scholar] [CrossRef] [PubMed]
  54. Jiao, W.L.; Hu, X.P.; Ren, H.; Xu, P.F.; Yu, R.B.; Chen, J.; Xing, X.R. Magnetic Ni and Ni/Pt hollow nanospheres and their catalytic activities for hydrolysis of ammonia borane. J. Mater. Chem. A 2014, 2, 18171–18176. [Google Scholar] [CrossRef]
  55. Li, Z.; He, T.; Matsumura, D.J.; Miao, S.; Wu, A.A.; Liu, L.; Wu, G.T.; Chen, P. Atomically Dispersed Pt on the Surface of Ni Particles: Synthesis and Catalytic Function in Hydrogen Generation from Aqueous Ammonia–Borane. ACS Catal. 2017, 7, 6762–6769. [Google Scholar] [CrossRef]
  56. Wan, C.; Zhu, M.Y.; Du, L.; Xu, L.X.; Ye, M.F.; An, Y. Highly efficient aerobic oxidation of tetralin to alpha-tetralone over MnOx-CoOy/γ-Al2O3 catalysts. Catal. Commun. 2019, 125, 87–92. [Google Scholar] [CrossRef]
  57. Yao, Q.L.; Lu, Z.H.; Huang, W.; Chen, X.S.; Zhu, J. High Pt-like activity of the Ni–Mo/graphene catalyst for hydrogen evolution from hydrolysis of ammonia borane. J. Mater. Chem. A 2016, 4, 8579–8583. [Google Scholar] [CrossRef]
  58. Wan, C.; Sun, L.; Xu, L.X.; Cheng, D.G.; Chen, F.Q.; Zhan, X.L.; Yang, Y.R. Novel NiPt alloy nanoparticle decorated 2D layered g-C3N4 nanosheets: A highly efficient catalyst for hydrogen generation from hydrous hydrazine. J. Mater. Chem. A 2019, 7, 8798–8804. [Google Scholar] [CrossRef]
  59. Aranishi, K.; Singh, A.K.; Xu, Q. Dendrimer-encapsulated bimetallic Pt-Ni nanoparticles as highly efficient catalysts for hydrogen generation from chemical hydrogen storage materials. ChemCatChem 2013, 5, 2248–2252. [Google Scholar] [CrossRef]
  60. Yang, X.J.; Cheng, F.Y.; Liang, J.; Tao, Z.L.; Chen, J. Carbon-supported Ni1-x@Ptx (x = 0.32, 0.43, 0.60, 0.67, and 0.80) core-shell nanoparticles as catalysts for hydrogen generation from hydrolysis of ammonia borane. Int. J. Hydrogen Energy 2011, 36, 1984–1990. [Google Scholar] [CrossRef]
  61. Zhang, M.Y.; Liu, L.; Lu, S.; Xu, L.X.; An, Y.; Wan, C. Facile Fabrication of NiPt/CNTs as an Efficient Catalyst for Hydrogen Production from Hydrous Hydrazine. ChemistrySelect 2019, 4, 10494–10500. [Google Scholar] [CrossRef]
  62. Hu, Y.J.; Wang, Y.Q.; Lu, Z.H.; Chen, X.S.; Xiong, L.H. Core–shell nanospheres Pt@SiO2 for catalytic hydrogen production. Appl. Surf. Sci. 2015, 341, 185–189. [Google Scholar] [CrossRef]
  63. Zhou, Q.X.; Xu, C.X. Nanoporous PtRu alloys with unique catalytic activity toward hydrolytic dehydrogenation of ammonia borane. Chem. Asian J. 2016, 11, 705–712. [Google Scholar] [CrossRef] [PubMed]
  64. Cao, N.; Hu, K.; Luo, W.; Cheng, G.Z. RuCu nanoparticles supported on graphene: A highly efficient catalyst for hydrolysis of ammonia borane. J. Alloy. Compd. 2014, 590, 241–246. [Google Scholar] [CrossRef]
  65. Wang, X.; Liu, D.P.; Song, S.Y.; Zhang, H.J. Graphene oxide induced formation of Pt–CeO2 hybrid nanoflowers with tunable CeO2 thickness for catalytic hydrolysis of ammonia borane. Chem. Eur. J. 2013, 19, 8082–8086. [Google Scholar] [CrossRef]
  66. Rachiero, G.P.; Demirci, U.B.; Miele, P. Bimetallic RuCo and RuCu catalysts supported on γ–Al2O3 a comparative study of their activity in hydrolysis of ammonia-borane. Int. J. Hydrogen Energy 2011, 36, 7051–7065. [Google Scholar] [CrossRef]
  67. Yang, X.J.; Cheng, F.Y.; Liang, J.; Tao, Z.L.; Chen, J. PtxNi1-x nanoparticles as catalysts for hydrogen generation from hydrolysis of ammonia borane. Int. J. Hydrogen Energy 2009, 34, 8785–8791. [Google Scholar] [CrossRef]
  68. Rakap, M. Poly(N–vinyl–2–pyrrolidone)–stabilized palladium–platinum nanoparticles–catalyzed hydrolysis of ammonia borane for hydrogen generation. J. Power Sources 2015, 276, 320–327. [Google Scholar] [CrossRef]
  69. Kalidendi, S.B.; Sanyal, U.; Jagirdar, B.R. Nanostructured Cu and Cu@Cu2O core shell catalysts for hydrogen generation from ammonia–borane. Phys. Chem. Chem. Phys. 2008, 10, 5870–5874. [Google Scholar] [CrossRef] [Green Version]
  70. Ma, H.; Na, C. Isokinetic Temperature and Size-Controlled Activation of Ruthenium-Catalyzed Ammonia Borane Hydrolysis. ACS Catal. 2015, 5, 1726–1735. [Google Scholar] [CrossRef]
  71. Gao, M.Y.; Yang, W.W.; Yu, Y.S. Monodisperse PtCu alloy nanoparticles as highly efficient catalysts for the hydrolytic dehydrogenation of ammonia borane. Int. J. Hydrogen Energy 2018, 43, 14293–14300. [Google Scholar] [CrossRef]
  72. Xu, D.; Wang, W.D.; Tian, M.; Dong, Z.P. Immobilization of Pt nanoparticles in hollow mesoporous silica nanocapsules: An aggregation- and leaching-resistant catalyst. J. Colloid Interface Sci. 2018, 516, 407–415. [Google Scholar] [CrossRef] [PubMed]
Scheme 1. Schematic illustration of the fabrication of PtNi/g-C3N4.
Scheme 1. Schematic illustration of the fabrication of PtNi/g-C3N4.
Catalysts 09 01009 sch001
Figure 1. XRD patterns of PtNi/g-C3N4 composites with different molar ratio of PtNi: (a) g-C3N4, (b) Ni/g-C3N4, (c) Pt/g-C3N4, (d) Pt0.8Ni0.2/g-C3N4, (e) Pt0.6Ni0.4/g-C3N4, (f) Pt0.5Ni0.5/g-C3N4, (g) Pt0.4Ni0.6/g-C3N4, and (h) Pt0.2Ni0.8/g-C3N4.
Figure 1. XRD patterns of PtNi/g-C3N4 composites with different molar ratio of PtNi: (a) g-C3N4, (b) Ni/g-C3N4, (c) Pt/g-C3N4, (d) Pt0.8Ni0.2/g-C3N4, (e) Pt0.6Ni0.4/g-C3N4, (f) Pt0.5Ni0.5/g-C3N4, (g) Pt0.4Ni0.6/g-C3N4, and (h) Pt0.2Ni0.8/g-C3N4.
Catalysts 09 01009 g001
Figure 2. FT-IR spectra of (a) g-C3N4, (b) Pt/g-C3N4, (c) Ni/g-C3N4, and (d) Pt0.5Ni0.5/g-C3N4.
Figure 2. FT-IR spectra of (a) g-C3N4, (b) Pt/g-C3N4, (c) Ni/g-C3N4, and (d) Pt0.5Ni0.5/g-C3N4.
Catalysts 09 01009 g002
Figure 3. X-ray photoelectron spectroscopy (XPS) spectra for catalyst Ni/g-C3N4, Pt/g-C3N4, and Pt0.5Ni0.5/g-C3N4 showing (a) Ni 2p and (b) Pt 4f.
Figure 3. X-ray photoelectron spectroscopy (XPS) spectra for catalyst Ni/g-C3N4, Pt/g-C3N4, and Pt0.5Ni0.5/g-C3N4 showing (a) Ni 2p and (b) Pt 4f.
Catalysts 09 01009 g003
Figure 4. (a) TEM images of Pt0.5Ni0.5/g-C3N4, (b) amplified High Resolution Transmission Electron Microscopy (HRTEM) image of Pt0.5Ni0.5/g-C3N4, (c) particle size distribution of Pt0.5Ni0.5 NPs, (d) high-angle annular dark-field scanning TEM (HAADF-STEM) image, and (g) mix distribution of C, N, Ni, and Pt of Pt0.5Ni0.5/g-C3N4, (e,f,h,i) C, Ni, N, and Pt elemental mapping images of Pt0.5Ni0.5/g-C3N4.
Figure 4. (a) TEM images of Pt0.5Ni0.5/g-C3N4, (b) amplified High Resolution Transmission Electron Microscopy (HRTEM) image of Pt0.5Ni0.5/g-C3N4, (c) particle size distribution of Pt0.5Ni0.5 NPs, (d) high-angle annular dark-field scanning TEM (HAADF-STEM) image, and (g) mix distribution of C, N, Ni, and Pt of Pt0.5Ni0.5/g-C3N4, (e,f,h,i) C, Ni, N, and Pt elemental mapping images of Pt0.5Ni0.5/g-C3N4.
Catalysts 09 01009 g004
Figure 5. (a) Time plots of catalytic dehydrogenation of AB (4 mmol) by PtNi/g-C3N4 catalyst with different ratios at 10 °C; and (b) time needed to complete the reaction and turnover frequency (TOF) values (obtained based on the overall Pt moles) of the PtNi/g-C3N4 catalysts.
Figure 5. (a) Time plots of catalytic dehydrogenation of AB (4 mmol) by PtNi/g-C3N4 catalyst with different ratios at 10 °C; and (b) time needed to complete the reaction and turnover frequency (TOF) values (obtained based on the overall Pt moles) of the PtNi/g-C3N4 catalysts.
Catalysts 09 01009 g005
Figure 6. (a) Plots of moles of H2 per mole of AB versus time for the hydrolysis of AB (4 mmol) in the presence of Pt0.5Ni0.5/g-C3N4 at different catalyst concentrations at 10 °C, and (b) the logarithmic plot of hydrogen evolution rate versus PtNi concentrations.
Figure 6. (a) Plots of moles of H2 per mole of AB versus time for the hydrolysis of AB (4 mmol) in the presence of Pt0.5Ni0.5/g-C3N4 at different catalyst concentrations at 10 °C, and (b) the logarithmic plot of hydrogen evolution rate versus PtNi concentrations.
Catalysts 09 01009 g006
Figure 7. (a) Plot of H2 mole versus time for hydrogen generation from AB hydrolysis catalyzed by Pt0.5Ni0.5/g-C3N4 catalyst at different AB concentrations ([Pt0.5Ni0.5/g-C3N4] = 0.100 g, T = 10 °C), and (b) the logarithmic plot of hydrogen evolution rate versus AB concentrations.
Figure 7. (a) Plot of H2 mole versus time for hydrogen generation from AB hydrolysis catalyzed by Pt0.5Ni0.5/g-C3N4 catalyst at different AB concentrations ([Pt0.5Ni0.5/g-C3N4] = 0.100 g, T = 10 °C), and (b) the logarithmic plot of hydrogen evolution rate versus AB concentrations.
Catalysts 09 01009 g007
Figure 8. (a) Plot of equivalent H2 per mole of AB versus time for hydrogen generation from AB hydrolysis catalyzed by Pt0.5Ni0.5/g-C3N4 catalyst at different temperatures ([Pt0.5Ni0.5/g-C3N4] = 0.100 g, [AB] = 4 mM), and (b) Arrhenius plot of ln k vs. (1/T).
Figure 8. (a) Plot of equivalent H2 per mole of AB versus time for hydrogen generation from AB hydrolysis catalyzed by Pt0.5Ni0.5/g-C3N4 catalyst at different temperatures ([Pt0.5Ni0.5/g-C3N4] = 0.100 g, [AB] = 4 mM), and (b) Arrhenius plot of ln k vs. (1/T).
Catalysts 09 01009 g008
Scheme 2. Possible mechanism of hydrogen evolution from NH3BH3 in aqueous solution over Pt0.5Ni0.5/g-C3N4.
Scheme 2. Possible mechanism of hydrogen evolution from NH3BH3 in aqueous solution over Pt0.5Ni0.5/g-C3N4.
Catalysts 09 01009 sch002
Figure 9. (a) Durability test of Pt0.5Ni0.5/g-C3N4 in ten runs for hydrogen generation from hydrolysis of aqueous AB solution, and (b) TEM image of Pt0.5Ni0.5/g-C3N4 after ten cycles.
Figure 9. (a) Durability test of Pt0.5Ni0.5/g-C3N4 in ten runs for hydrogen generation from hydrolysis of aqueous AB solution, and (b) TEM image of Pt0.5Ni0.5/g-C3N4 after ten cycles.
Catalysts 09 01009 g009
Table 1. Catalytic activities and the activation energy of catalysts in the hydrolysis of AB.
Table 1. Catalytic activities and the activation energy of catalysts in the hydrolysis of AB.
CatalystsTOF (molH2min−1mol−1M) M = Pt, Ru, AgEa (kJ mol−1)Refs.
Pt0.5Ni0.5/g-C3N4250.838.09This work
NP–Pt40Co60 composite13138.840
Pt@SiO215853.662
PtRu59.638.963
RuCu/graphene13530.8964
Pt/CeO2/RGO48-65
RuCo(1:1)/γ–Al2O332.94766
Pt0.65Ni0.3544.339.067
hnp–Pt35Cu6510840.538
Pd–Pt@PVP NPs12551.768

Share and Cite

MDPI and ACS Style

Zhang, M.; Xiao, X.; Wu, Y.; An, Y.; Xu, L.; Wan, C. Hydrogen Production from Ammonia Borane over PtNi Alloy Nanoparticles Immobilized on Graphite Carbon Nitride. Catalysts 2019, 9, 1009. https://doi.org/10.3390/catal9121009

AMA Style

Zhang M, Xiao X, Wu Y, An Y, Xu L, Wan C. Hydrogen Production from Ammonia Borane over PtNi Alloy Nanoparticles Immobilized on Graphite Carbon Nitride. Catalysts. 2019; 9(12):1009. https://doi.org/10.3390/catal9121009

Chicago/Turabian Style

Zhang, Mingya, Xue Xiao, Yan Wu, Yue An, Lixin Xu, and Chao Wan. 2019. "Hydrogen Production from Ammonia Borane over PtNi Alloy Nanoparticles Immobilized on Graphite Carbon Nitride" Catalysts 9, no. 12: 1009. https://doi.org/10.3390/catal9121009

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop