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Article

Ta3N5 Nanobelt-Loaded Ru Nanoparticle Hybrids’ Electrocatalysis for Hydrogen Evolution in Alkaline Media

by
Xinyu Zhang
1,
Lulu Xu
1,
Xingcai Wu
1,*,
Yourong Tao
1,* and
Weiwei Xiong
2,*
1
Key Laboratory of Mesoscopic Chemistry of MOE, State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
2
School of Environmental & Chemical Engineering, Jiangsu University of Science and Technology, Jiangsu 212003, China
*
Authors to whom correspondence should be addressed.
Molecules 2023, 28(3), 1100; https://doi.org/10.3390/molecules28031100
Submission received: 26 December 2022 / Revised: 11 January 2023 / Accepted: 16 January 2023 / Published: 21 January 2023
(This article belongs to the Special Issue Nanomaterials: Synthesis of New Few- or Free-Noble Metal Electrocatalysts for Water Splitting)
Browse Figures
Review Reports Versions Notes

Abstract

:
Electrochemical hydrogen evolution is a highly efficient way to produce hydrogen, but since it is limited by high-cost electrocatalysts, the preparation of high-efficiency electrocatalysts with fewer or free noble metals is important. Here, Ta3N5 nanobelt (NB)-loaded Ru nanoparticle (NP) hybrids with various ratios, including 1~10 wt% Ru/Ta3N5, are constructed to electrocatalyze water splitting for a hydrogen evolution reaction (HER) in alkaline media. The results show that 5 wt% Ru/Ta3N5 NBs have good HER properties with an overpotential of 64.6 mV, a Tafel slope of 84.92 mV/dec at 10 mA/cm2 in 1 M of KOH solution, and good stability. The overpotential of the HER is lower than that of Pt/C (20 wt%) at current densities of 26.3 mA/cm2 or more. The morphologies and structures of the materials are characterized by scanning electron microscopy and high-resolution transmission electron microscopy, respectively. X-ray photoelectron energy spectroscopy (XPS) demonstrates that a good HER performance is generated by the synergistic effect and electronic transfer of Ru to Ta3N5. Our electrochemical analyses and theoretical calculations indicate that Ru/Ta3N5 interfaces play an important role as real active sites.

Graphical Abstract

1. Introduction

Hydrogen is a high-energy-density and environmentally friendly gas. Its only combustion product is pollution-free water, so hydrogen is considered an ideal alternative to traditional fossil fuels and is important in future energy systems [1,2]. Research demonstrates that water electrolysis [3,4,5,6] and photoelectrolysis [7,8] are very effective methods of hydrogen production, which can convert solar and wind energies into hydrogen fuel [9,10]. However, large-scale electrochemical hydrogen evolution is still a challenge because it is limited by high-cost and inefficient electrocatalysts. Water electrolysis is usually carried out in alkaline or acid aqueous solution to improve conductivity. Because of its suitable manufacture safety and stable output, alkaline hydrogen evolution reaction (HER) is considered an important cathode reaction, with application potential in the chlor-alkali industry and anion exchange membrane (AEM)-based water electrolysis. Compared with acidic HER, alkaline HER can use various non-precious metal materials for electrocatalysis, such as transition metal oxides, phosphides, carbides, sulfides, and so on [11,12,13,14]. Nevertheless, alkaline HER is generally rather inactive at a high current density due to the low proton concentration. The sluggish kinetics of alkaline HER derived from extra water dissociation can result in higher overpotentials and reaction rates 2–3 orders of magnitude lower than those in the acid condition [15]. Therefore, developing high-efficiency and low-cost electrocatalysts to accelerate the alkaline HER kinetics is very important for water electrolysis.
Platinum (Pt) is considered the best HER electrocatalyst due to its optimal hydrogen adsorption energy [16,17], but it cannot yet be applied large-scale because it is rare in nature. Ruthenium (Ru) has a higher natural abundance than Pt, and its price is only 1/25 that of Pt [18,19]. Its hydrogen binding energy (65 Kcal mol−1) is slightly higher than that of Pt (62 Kcal mol−1) to increase the energy of hydrogen desorption, to prevent the regeneration of active sites [18]. If Ru is modified, alloyed, or doped, its HER catalytic activity can visibly improves [20,21,22,23]. For example, Sun et al. prepared a B-Ru@CNT (carbon nanotube) electrocatalyst with excellent HER activity, yielding overpotentials of 17 and 62 mV at a current density of 10 mA cm−2 in alkaline and acidic solutions, respectively. These experimental and theoretical results indicate that the incorporation of B weakens the Ru–H bond and downshifts the d-bond center of Ru from the Fermi level by reducing the electron density of Ru [24]. Similarly, the 3 wt% Ru/CeO2 electrocatalyst also demonstrates excellent HER performance, which confirms the downshift of the d-band of Ru, and the reduction of the Ru–H bond energy [25]. Therefore, Ru is an up and coming material for electrocatalytic HER. Ta3N5 is a red powder with an octahedral structure and a narrow band gap of about 2.08 eV, which has good photosensitive properties [26] and is widely applied in solar-driven photocatalytic or photoelectrochemical (PEC) water splitting [27,28]. Its analog TaON is also a good photosensitive agent [29] and an ideal photoelectro-catalyst for hydrogen evolution [30,31]. This begs the question, if Ru/Ta3N5 is used in electrocatalytical HER under a non-solar-driven condition, how do its properties support HER?
Here, Ta3N5 nanobelts (NBs) are used as a supporter of Ru nanoparticles to construct electrocatalysts for water splitting in alkaline media. The results show that the hydrogen evolution performance of 5 wt% Ru/Ta3N5 NBs is comparable to 20 wt% Pt/C. This excellent performance is due to the valence electrons on the Ru surface transferring to Ta3N5, which favors the dissociation of water and reduces the adsorption energy of hydrogen.

2. Results

2.1. Structures and Morphologies of Catalysts

To prepare Ru/Ta3N5 NBs, we synthesized TaS3 NBs and then converted them to Ta3N5 NBs in NH3 atmospheres. Subsequently, various quantities of Ru3+ were adsorbed on the surface of Ta3N5 NBs by the dipping method, before Ru was loaded on the Ta3N5 NBs by reduction. The structures and morphologies of the catalysts were characterized by X-ray diffractometry (XRD) and scanning electron microscopy (SEM), respectively.
Figure 1a–d show the SEM images of TaS3 NBs, Ta3N5 NBs, 5 wt% Ru/Ta3N5 NBs, and 5 wt% Ru/TaS3 NBs, respectively, which reveal that TaS3 NBs are nanobelts with a width of 1–4 μm, a thickness of about 10–200 nm, and a length of up to a centimeter, and that the sizes of Ta3N5 NBs are close to those of TaS3 NBs. Because Ru nanoparticles (NPs) were loaded on the surface of Ta3N5 and TaS3 NBs by reduction of Ru3+ in an aqueous solution, the lengths of Ta3N5 and TaS3 NBs were diminished. The sizes of Ru NPs loaded were about 3–15 nm. Figure 1e shows the XRD patterns of TaS3 NBs, Ta3N5 NBs, 5 wt% Ru/Ta3N5 NBs, and 5 wt% Ru/TaS3 NBs. TaS3 and Ta3N5 NBs were assigned to orthogonal phases of TaS3 (JCPDS no. 18-1313) and Ta3N5 (JCPDS no. 79-1533), respectively [26]. No Ru diffraction peaks can be observed in the XRD profiles of 5 wt% Ru/TaS3 and 5 wt% Ru/Ta3N5, which may be attributed to the small size and low load of Ru.
The Ta, N, and Ru elements in the 5 wt% Ru/Ta3N5 NBs are confirmed by the energy dispersive X-ray spectroscopy (EDX) shown in Figure 1f, and the mass ratio (%) of Ta, N and Ru is 83.98:14.00:2.02, demonstrating that the percentage of Ru is lower than 5 wt% (real value), although it is possible that the EDX analysis is only approximate.
Figure 2a,b present the high-resolution transmission electron microscopy (HRTEM) images of 5 wt% Ru/Ta3N5 NBs, and it is evident that the addition of Ru does not alter the morphology of Ta3N5. The Ru NPs with a size of about 3–15 nm can be observed on Ta3N5. As shown in Figure 2a,b, lattice stripe spacing of 0.22 nm and 0.50 nm belong to the (100) plane of Ru and the (002) plane of Ta3N5, respectively.
To find the optimal load for Ru, we prepared Ru/Ta3N5 NB catalysts with different mass fractions of Ru (1 wt%, 3 wt%, 7 wt%, and 10 wt%). Figure 3a–d show SEM images of those, respectively, and the XRD patterns are shown in Figure S1, which are indexed as orthogonal Ta3N5 (JCPDS no. 79-1533). Because Ru NPs are too little or the strong peak (2θ: 44°) of Ru overlaps with that of Ta3N5, it is difficult to observe the Ru peak.

2.2. The Surface Properties

Figure 4a–d present the X-ray photoelectron energy spectroscopy (XPS) of Ru NPs, Ta3N5 NBs, and 5 wt% Ru/Ta3N5 NBs. Figure 4a shows the XPS survey spectra of those, which further confirm the existence of Ru, N, and Ta in 5 wt% Ru/Ta3N5 NBs. As shown in Figure 4b, the peaks at 396.23 eV and 403.28 eV of 5 wt% Ru/Ta3N5 NBs correspond to the binding energies (BEs) of N 1s and Ta 4p3/2, respectively, while the peaks at 395.89 eV and 403.11 eV of Ta3N5 NBs correspond to the BEs of N 1s and Ta 4p3/2 [32,33], respectively. Figure 4c presents the fine XPS spectra of Ta 4f of the Ta3N5 and 5 wt% Ru /Ta3N5 NBs. The two peaks at 24.21 and 26.17 eV of 5% Ru/Ta3N5 correspond to the BEs of Ta 4f7/2 and Ta 4f5/2, respectively, while the two peaks at 24.24 eV and 26.16 eV correspond to the BEs of Ta 4f7/2 and Ta 4f5/2 of Ta3N5, respectively.
Figure 4d presents the Ru 3d5/2 spectra of 5 wt% Ru /C and 5% Ru/Ta3N5 NBs, where the peaks at 280.30 and 281.46 eV correspond to their Ru3d5/2 BEs, respectively, and the bias is 1.2 eV. The increase in the Ru 3d5/2 BEs from 5 wt% Ru/C to 5 wt% Ru/Ta3N5NBs demonstrates that the electrons of Ru transfer to Ta3N5 on the surface of 5 wt% Ru/Ta3N5NBs so that the adsorption energy of H on Ru lowers, which is helpful to increase the electrocatalytic activity for HER.

2.3. Hydrogen Evolution Performance

Figure 5a,b show the linear scanning voltammetry (LSV) and Tafel curves of 5 wt% Ru/Ta3N5 NBs, Ta3N5 NBs, 5 wt% Ru/TaS3 NBs, Ru (5 wt% Ru/C, C: conductive carbon), and 20 wt% Pt/C in 1M of nitrogen-saturated KOH solution at a rotating rate of 1600 rpm and a scanning rate of 5 mV/s.
Their overpotentials are 64.6, 394.6, 261.6, 96.6, and 49 mV at a current density of 10 mA/cm2, respectively, while their Tafel slopes are 84.92, 135.98, 139.24, 123.04, and 59.9 mV/dec, respectively. Clearly, the activity of 5 wt% Ru/Ta3N5 NBs for HER is superior to those of the other three, except for 20 wt% Pt/C at 10 mA/cm2, but when the current density is greater than 26.3 mA/cm2, the activity of 5 wt% Ru/Ta3N5 NBs is superior to 20 wt% Pt/C. Because the HER properties of 5 wt% Ru/Ta3N5 NBs are superior to 5 wt% Ru/ TaS3 NBs, Ta3N5 NBs as supporters are better than TaS3 NBs.
In order to compare the effects of different Ru-loaded quantities on HER, we experimented on Ru/Ta3N5 NBs with various ratios. Figure 5c,d demonstrate the LSV and Tafel curves of 1 wt%, 3 wt%, 5 wt%, 7 wt%, and 10 wt% Ru/Ta3N5 NBs, respectively, where their overpotentials are 176.6, 154.6, 64.6, 214.6, and 220.6 mV at a current density of 10 mA/cm2, respectively, and their Tafel slopes are 119.38, 109.72, 84.92, 138.31, and 135.08 mV/dec, respectively, so 5 wt% for Ru/Ta3N5 NBs is the optimal ratio. Because 5 wt% for Ru/Ta3N5 NBs has the gentlest Tafel slope, this reveals it has favorable electrocatalytic kinetics with a high transfer coefficient.
To explain the difference in the catalytic activities, the Cdl (double-layer capacitance) of 5 wt% Ru/Ta3N5 NBs, Ta3N5 NBs, and 5 wt% Ru/TaS3 NBs was measured as 7.28, 3.74, and 1.94 mF/cm2, respectively, as shown in Figure 5e, and the CV curves at 1.1–1.35 V are shown in Figure S2 (Supplementary Materials). The Cdl values of 1 wt%, 3 wt%, 5 wt%, 7 wt%, and 10 wt% Ru/Ta3N5 NBs were measured as 4.12, 3.99, 7.28, 3.81, and 3.54 mF/cm2, respectively, as shown in Figure 5f, and the CV curves at 1.1–1.35 V are shown in Figure S2. Hence, the good catalytic activity of 5 wt% Ru/Ta3N5 NBs can be attributed to their high electrochemical activity surface area (ECSA).
Electrochemical impedance spectroscopy (EIS) reveals the interfacial properties between the electrolyte and the electrode, and the semicircle in the high-frequency region (Nyquist plot) represents the charge transfer process. Figure 6a shows the Nyquist plots of 5 wt% Ru/Ta3N5 NBs, Ta3N5 NBs, 5 wt% Ru/TaS3 NBs, and Ru NPs (5% Ru/C) measured in 1 M KOH of nitrogen saturation, where Z′ and Z′′ are real and imaginary parts of the impedance, respectively. The NBs’ and NPs’ transfer resistances (Rct) are 9.721, 4621, 73.51, and 72.78 ohm, respectively. Figure 6b shows the Nyquist plots of 1 wt%, 3 wt%, 5 wt%, 7 wt%, and 10 wt% Ru/Ta3N5NBs measured in 1 M KOH of nitrogen saturation. Their transfer resistances (Rct) are 161.7, 77.56, 9.721, 71.07, and 32.35 ohm, respectively. The equivalent circuit of the Nyquist plots fitted is shown in the inset of Figure 6a. Because the transfer resistance of 5 wt% Ru/Ta3N5 NBs is minimal, the electron transfer rate of HER increases, which is helpful to improve the electrocatalytic activity. Figure 6c shows the chronoamperometric curves of the 5% Ru/Ta3N5 NBs coated on 0.5 cm × 0.5 cm foam nickel at 10 and 40 mA/cm2 for 25 h (the slurry is the same as that used in GCE), which confirms the good hydrogen evolution stability of the materials. For comparison, a few results for Ru are included in Table 1.
In order to theoretically inspect the enhanced effect of interfaces on the distinguished HER, we also conducted density functional calculations on the adsorption of H+ on the surface and interface of Ru/Ta3N5. The adsorption free energy of hydrogen (ΔGH*) on the catalyst surface is recognized as the main descriptor to evaluate the HER activity in both acidic and alkaline solutions. An excellent HER catalyst requires an optimal ΔG H* value close to zero or that of Pt. The ΔGH* values of the H adsorption on the different sites of Ru, Ta3N5, and Ru/Ta3N5 are shown in Figure 6d, and corresponding adsorption structures are shown in Figure 7a–f. By comparison, the ΔGH* of Ta3N5–Ru–H4 reveals that the adsorption structure, as shown in Figure 7f, is the least developed (−0.104 eV) as it is close to zero, so the site of the Ru atom near the interface is the best site of H adsorption.

3. Materials and Methods

3.1. Experimental Reagents

Tantalum (Ta) plates (99.5%), sulfur powders (99.99%), iodine powders (99.8%), RuCl3·H2O (98%), and NaBH4 (98%) were bought from China National Chemical Reagent Co., Ltd. NH3 (99%) was bought from Nanjing Tianze Gas Co., Ltd., Nanjing, China.

3.2. Preparation of the Catalysts

The prepared procedures were divided into three steps. Firstly, a 524.5 mg Ta plate (5 mm × 0.2 mm × 30 mm), sulfur powder (Ta: S molar ratio = 2:1), and 10 mg of iodine were weighed, placed in quartz tubes (Φ0.6 cm × 10 cm), and sealed by a hydrogen torch in a 10−2 Pa vacuum. The sealed quartz tube was placed in a horizontal furnace (Φ 4 cm × 32 cm) with a temperature gradient from the center to both sides of above 10 °C/cm, where the reagent was in the center of the furnace. The furnace was heated from room temperature to 550 °C at 10 °C/min, and maintained for 6 h, then naturally cooled to room temperature before TaS3 NBs were scraped from Ta substrate. Secondly, the TaS3 NBs were placed in a ceramic boat and put in the center of the horizontal furnace, heated from room temperature to 850 °C in flowing NH3 (100 mL/min), and maintained at 850 °C for 3 h, then naturally cooled to room temperature so that Ta3N5 NBs were obtained. Thirdly, 20 mg Ta3N5 NBs were added to a round-bottomed flask with 10 mL of ethanol and 20 mL of deionized water, then stirred to form a uniform suspension. Subsequently, 1.117 mL of 2 mg/mL RuCl3·H2O solution was injected and stirring continued for 12 h before 1.0 mL of NaBH4 aqueous solution (NaBH4:Ru = 3:1 mol/mol) was slowly added to the above system, and stirring resumed for 1 h. Finally, the products were separated by multiple centrifugation and washed with deionized water and ethanol. The collected products were dried by vacuuming at 60 °C to form the 5 wt% Ru/Ta3N5 NBs catalyst, and 5 wt% Ru/C and 5 wt% Ru/TaS3 NBs were similarly prepared. Ru/Ta3N5 NBs with different percentages of Ru and Ta3N5 NBs (1, 3, 7 and 10 wt%) were also prepared by adjusting the ratio of Ru and Ta3N5 in the NBs.

3.3. Characterization

The structure and morphology of the products were characterized by a Rigaku D/Max-rC diffractometer (XRD) with monochromatized Cu Kα1-radiation (λ = 1.5406 Å), a S-4800 scanning electron microscope (SEM) with an energy dispersive X-ray spectrometer (EDX), and a JEOL-JEM-2010 high-resolution transmission electron microscope (HRTEM) with image and selected area electron diffraction (SAED). The valence states of the surface elements were analyzed by X-ray photoelectron energy spectroscopy (XPS, PHI 5000 Versa Probe, A1 Kα radiation, hν =1486.6 eV, Japan), and the binding energy was corrected based on C1s = 284.6 eV.

3.4. Electrochemical Performance Test

The 8 mg catalyst and 0.5 mg of carbon black (Vulcan XC-72) were dispersed in 500 μL of aqueous solution and sonicated for 20 min to disperse into uniform ink. Then, 5 μL of catalyst ink and 3 μL of Nafion were injected into a polished glass carbon electrode (GCE, surface area 0.1256 cm2) to naturally dry. Through the same method, the 20 wt% Pt/C catalyst was coated on GCE. All electrochemical measurements were performed by a three-electrode system at the electrochemical workstation (CHI 760E, Chenhua, China). The three-electrode system was formed with the carbon rod as the counter electrode, Hg/HgO as the reference electrode, and the rotating disk electrode with GCE as the working electrode. Electrochemical tests were performed in 1 M of KOH solution at room temperature. The electrocatalytic properties for hydrogen evolution under an alkaline solution were determined by linear scanning voltammetry (LSV, 5 mV/s, negative sweep), circulating voltammetry (CV, 50 mV/s, negative sweep), electrochemical impedance spectrum (EIS), and chronoamperometry methods. The electrochemical activity surface areas (ECSAs) of catalysts were measured by the double-layer capacitance (Cdl) method because Cdl is proportional to ECSA. ECSA = Cdl/Cs, where Cdl is the double-layer capacitance and Cs is the specific capacitance of a planar surface that is atomically smooth under identical electrolyte conditions (Cs = 40 μF·cm−2 in this case) [34]. The Cdl values were measured by the CV curves at 1.1–1.35 V and by changing the scanning speed (10–100 mV/s). Cdl = (ja − jc)/(2v) = Δj/(2v), where ja and jc are the anodic and cathodic voltametric current densities, respectively, and v is the scan rate. The EIS was tested at a frequency of 104–10−2 Hz, amplitude of 5 mV, and rotational speed of 1600 rpm. All the potential values measured were corrected by the reversible hydrogen electrode potential (RHE): ERHE = EHg/HgO + 0.0591 pH + 0.095 V.

3.5. Theoretical Computation

The Dmol3 module in the Materials Studio 8.0 package was employed to perform the spin polarization DFT calculations, and the exchange–correlation energy is depicted by the functional of generalized gradient approximation in the Perdew–Becke–Ernzerhof (PBE) form. The double numerical plus polarization (DNP) basis set was adopted, while accurate DFT Semi-Core Pseudopots (DSPP) was used for the metal atoms. All models were calculated in periodical boxes with a vacuum slab of 15 Å to separate the interaction between periodic images [35]. More details of the DFT calculations can be found in Supplementary Materials.

4. Conclusions

In this project, we studied the electrocatalytic hydrogen evolution performance of 1~10% Ru/Ta3N5 NBs, Ta3N5 NBs, and 5 wt% Ru/TaS3 NBs in alkaline media. We discovered that 5 wt% Ru/Ta3N5NBs had good HER properties with an overpotential of 64.6 mV and a Tafel slope of 84.92 mV/dec at 10 mA/cm2. The good HER performance of 5 wt% Ru/Ta3N5 stems from the synergistic effect and electronic transfer of Ru to Ta3N5. This article provides an efficient method for designing low-cost and efficient transition Ru-based electrocatalysts for HER.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/molecules28031100/s1, Figure S1: XRD patterns of Ta3N5 NBs and 1, 3, 7, and 10 wt% Ru/Ta3N5 NBs; Figure S2: CV curves at potentials from 1.1 to 1.35 V in a nitrogen-saturated 1 M KOH (vs. RHE) of Ta3N5 NBs, 1, 3, 5, 7, and 10 wt% Ru/Ta3N5 NBs, and 5 wt% Ru/TaS3 NBs; Data S1: Detailed DFT calculations.

Author Contributions

Data curation, writing—original draft preparation: X.Z. and L.X.; visualization, investigation: Y.T.; conceptualization, methodology, software, writing—reviewing and editing: X.W. and W.X. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the National Nature Science Foundations of China (nos. 21673108 and 2210060309) and the Open Foundations of the State Key Laboratory of Coordination Chemistry (SKLCC1917).

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

No new data were created except for the data in the Supplementary Materials and the paper.

Conflicts of Interest

The authors declare no conflict of interest.

Sample Availability

Samples of the compounds are available from the authors.

References

  1. Wang, T.; Wang, X.J.; Liu, Y.; Zheng, J.; Li, X.G. A highly efficient and stable biphasic nanocrystalline Ni–Mo–N catalyst for hydrogen evolution in bothacidic and alkaline electrolytes. Nano Energy 2016, 22, 111–119. [Google Scholar] [CrossRef]
  2. Fan, X.J.; Zhou, H.Q.; Guo, X. WC nanocrystals grown on vertically aligned carbon nanotubes: An efficient and stable electrocatalyst for hydrogen evolution reaction. ACS Nano 2015, 9, 5125–5134. [Google Scholar] [CrossRef] [PubMed]
  3. Xu, X.M.; Shao, Z.P.; Jiang, S.P. High-entropy materials for water electrolysis. Energy Technol. 2022, 10, 2200573. [Google Scholar] [CrossRef]
  4. Abdelghafar, F.; Xu, X.M.; Jiang, S.P.; Shao, Z.P. Designing single-atom catalysts toward improved alkaline hydrogen evolution reaction. Mater. Rep. Energy 2022, 2, 100144. [Google Scholar] [CrossRef]
  5. Xu, X.M.; Pan, Y.L.; Zhong, Y.J.; Ge, L.; Jiang, S.P.; Shao, Z.P. From scheelite BaMoO4 to perovskite BaMoO3: Enhanced electrocatalysis toward the hydrogen evolution in alkaline media. Compos. Part B Eng. 2020, 198, 108214. [Google Scholar] [CrossRef]
  6. Lv, Y.L.; Batool, A.; Wei, Y.X.; Xin, Q.; Boddula, R.; Jan, S.U.; Akram, M.Z.; Tian, L.Q.; Guo, B.D.; Gong, J.R. Homogeneously distributed NiFe alloy nanoparticles on 3D carbon fiber network as a bifunctional electrocatalyst for overall water splitting. ChemElectroChem 2019, 6, 2497–2502. [Google Scholar] [CrossRef]
  7. Boddula, R.; Xie, G.C.; Guo, B.D.; Gong, J.R. Role of transition-metal electrocatalysts for oxygen evolution with Si-based photoanodes. Chin. J. Catal. 2021, 42, 1387–1394. [Google Scholar] [CrossRef]
  8. Boddula, R.; Guo, B.D.; Ali, A.; Xie, G.C.; Dai, Y.W.; Zhao, C.; Wei, Y.X.; Jan, S.U.; Gong, J.R. Synergetic effects of dual electrocatalysts for high-performance solar-driven water oxidation. ACS Appl. Energy Mater. 2019, 2, 7256–7262. [Google Scholar] [CrossRef]
  9. Ji, Z.; Trickett, C.; Pei, X.K.; Yaghi, O.M. Linking molybdenum–sulfur clusters for electrocatalytic hydrogen evolution. J. Am. Chem. Soc. 2018, 140, 13618–13622. [Google Scholar] [CrossRef]
  10. Zhang, J.Q.; Zhao, Y.F.; Guo, X.; Chen, C.; Dong, C.L.; Liu, R.S.; Han, C.P.; Li, Y.D.; Gogotsi, Y.; Wang, G.X. Single platinum atoms immobilized on an MXene as an efficient catalyst for the hydrogen evolution reaction. Nat. Catal. 2018, 1, 985–992. [Google Scholar] [CrossRef]
  11. Zheng, C.; Zhu, Z.Z.; Wang, S.B.; Hou, Y.D. NaF-assisted hydrothermal synthesis of Ti-doped hematite nanocubes with enhanced photoelectrochemical activity for water splitting. Appl. Surf. Sci. 2015, 359, 805–811. [Google Scholar] [CrossRef]
  12. Lu, X.F.; Yu, L.; Lou, X.W. Highly crystalline Ni-doped FeP/carbon hollow nanorods as all-pH efficient and durable hydrogen evolving electrocatalysts. Sci. Adv. 2019, 5, eaav6009. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  13. Lu, X.F.; Yu, L.; Zhang, J.T.; Lou, X.W. Ultrafine dual-phased carbide nanocrystals confined in porous nitrogen-doped carbon dodecahedrons for efficient hydrogen evolution reaction. Adv. Mater. 2019, 31, 1900699. [Google Scholar] [CrossRef] [PubMed]
  14. Zhong, X.W.; Zhang, L.F.; Tang, J.; Chai, J.W.; Xu, J.C.; Cao, L.J.; Yang, M.Y.; Yang, M.; Kong, W.G.; Wang, S.J.; et al. Efficient coupling of a hierarchical V2O5@Ni3S2 hybrid nanoarray for pseudocapacitors and hydrogen production. J. Mater. Chem. A 2017, 5, 17954–17962. [Google Scholar] [CrossRef]
  15. Safizadeh, F.; Ghali, E.; Houlachi, G. Electrocatalysis developments for hydrogen evolution reaction in alkaline solutions–a Review. Int. J. Hydrogen Energy 2015, 40, 256–274. [Google Scholar] [CrossRef]
  16. Li, Y.J.; Zhang, H.C.; Xu, T.H.; Lu, Z.Y.; Wu, X.C.; Wan, P.B.; Sun, X.M.; Jiang, L. Under-water superaerophobic pine-shaped Pt nanoarray electrode for ultrahigh-performance hydrogen evolution. Adv. Funct. Mater. 2015, 25, 1737–1744. [Google Scholar] [CrossRef]
  17. Yan, Y.; Xia, B.Y.; Xu, Z.C.; Wang, X. Recent development of molybdenum sulfides as advanced electrocatalysts for hydrogen evolution reaction. ACS Catal. 2014, 4, 1693–1705. [Google Scholar] [CrossRef]
  18. Mahmood, J.; Li, F.; Jung, S.M.; Okyay, M.S.; Ahmad, I.; Kim, S.J.; Park, N.; Jeong, H.Y.; Baek, J.B. An efficient and pH-universal ruthenium-based catalyst for the hydrogen evolution reaction. Nat. Nanotechnol. 2017, 12, 441–446. [Google Scholar] [CrossRef]
  19. Wu, K.L.; Sun, K.A.; Liu, S.J.; Cheong, W.C.; Chen, Z.; Zhang, C.; Pan, Y.; Cheng, Y.S.; Zhuang, Z.W.; Wei, X.W.; et al. Atomically dispersed Ni–Ru–P interface sites for high-efficiency pH-universal electrocatalysis of hydrogen evolution. Nano Energy 2021, 80, 105467. [Google Scholar] [CrossRef]
  20. Peng, J.; Chen, Y.H.; Wang, K.; Tang, Z.H.; Chen, S.W. High-performance Ru-based electrocatalyst composed of Ru nanoparticles and Ru single atoms for hydrogen evolution reaction in alkaline solution. Int. J. Hydrogen Energy 2020, 45, 18840–18849. [Google Scholar] [CrossRef]
  21. Li, H.J.W.; Liu, K.; Fu, J.W.; Chen, K.J.; Yang, K.X.; Lin, Y.Y.; Yang, B.P.; Wang, Q.Y.; Pan, H.; Cai, Z.J.; et al. Paired Ru–O–Mo ensemble for efficient and stable alkaline hydrogen evolution reaction. Nano Energy 2021, 82, 105767. [Google Scholar] [CrossRef]
  22. Li, Q.Q.; Huang, F.Z.; Li, S.K.; Zhang, H.; Yu, X.Y. Oxygen vacancy engineering synergistic with surface hydrophilicity modification of hollow Ru doped CoNi-LDH nanotube arrays for boosting hydrogen evolution. Small 2022, 18, 2104323. [Google Scholar] [CrossRef] [PubMed]
  23. Su, J.W.; Yang, Y.; Xia, G.L.; Chen, J.T.; Jiang, P.; Chen, Q.W. Ruthenium-cobalt nanoalloys encapsulated in nitrogen-doped graphene as active electrocatalysts for producing hydrogen in alkaline media. Nat. Commun. 2017, 8, 14969. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  24. Sun, X.Z.; Li, W.H.; Chen, J.; Yang, X.L.; Wu, B.F.; Wang, Z.X.; Li, B.; Zhang, H.B. Boron-induced activation of Ru nanoparticles anchored on carbon nanotubes for the enhanced pH-independent hydrogen evolution reaction. J. Colloid Interface Sci. 2022, 616, 338–346. [Google Scholar] [CrossRef]
  25. Wang, W.; Tao, Y.R.; Wu, X.C.; Yang, L.J. Flower-like CeO2-supported small-sized Ru nanoparticle hybrids for highly efficient alkaline hydrogen evolution: Roles of interfacial effects. Appl. Surf. Sci. 2022, 581, 152256. [Google Scholar] [CrossRef]
  26. Wu, X.C.; Tao, Y.R.; Li, L.; Bando, Y.; Golberg, D. Centimeter-long Ta3N5 nanobelts: Synthesis, electrical transport, and photoconductive properties. Nanotechnology 2013, 24, 175701. [Google Scholar] [CrossRef]
  27. Fu, J.; Wang, F.Z.; Xiao, Y.Q.; Yao, Y.S.; Feng, C.; Chang, L.; Jiang, C.M.; Kunzelmann, V.F.; Wang, Z.M.; Govorov, A.O.; et al. Identifying performance-limiting deep traps in Ta3N5 for solar water splitting. ACS Catal. 2020, 10, 10316–10324. [Google Scholar] [CrossRef]
  28. Guo, Q.H.; Zhao, J.J.; Yang, Y.; Huang, J.L.; Tang, Y.T.; Zhang, X.L.; Li, Z.H.; Yu, X.; Shen, J.; Zhao, J.W. Mesocrystalline Ta3N5 superstructures with long-lived charges for improved visible light photocatalytic hydrogen production. J. Colloid Interface Sci. 2020, 560, 359–368. [Google Scholar] [CrossRef]
  29. Tao, Y.R.; Chen, J.Q.; Wu, X.C. Phototransistor based on single TaON nanobelt and its photoresponse from ultraviolet to near–infrared. J. Inorg. Mater. 2019, 34, 1004–1010. [Google Scholar]
  30. Higashi, M.; Domen, K.; Abe, R. Fabrication of efficient TaON and Ta3N5 photoanodes for water splitting under visible light irradiation. Energy Environ. Sci. 2011, 4, 4138–4147. [Google Scholar] [CrossRef]
  31. Pei, L.; Wang, H.X.; Wang, X.H.; Xu, Z.; Yan, S.C.; Zou, Z.G. Nanostructured TaON/Ta3N5 as a highly efficient type-II heterojunction photoanode for photoelectrochemical water splitting. Dalton Trans. 2018, 47, 8949–8955. [Google Scholar] [CrossRef] [PubMed]
  32. Pei, L.; Yuan, Y.J.; Zhong, J.S.; Li, T.Z.; Yang, T.; Yan, S.C.; Ji, Z.G.; Zou, Z.G. Ta3N5 nanorods encapsulated into 3D hydrangea-like MoS2 for enhanced photocatalytic hydrogen evolution under visible light irradiation. Dalton Trans. 2019, 48, 13176–13183. [Google Scholar] [CrossRef] [PubMed]
  33. Kim, Y.W.; Cha, S.; Kwak, I.; Kwon, I.S.; Park, K.; Jung, C.S.; Cha, E.H.; Park, J. Surface-modified Ta3N5 nanocrystals with boron for enhanced visible-light-driven photoelectrochemical water splitting. ACS Appl. Mater. Interfaces 2017, 9, 36715–36722. [Google Scholar] [CrossRef] [PubMed]
  34. Zhu, S.N.; Wang, W.; Tao, Y.R.; Zhang, X.Y.; Wu, X.C.; Zhang, D.M. Co3O4/CeO2 Heterojunction: Preparation electrocatalytic oxygen evolution performance in alkaline medium. Chin. J. Inorg. Chem. 2021, 37, 1337–1344. [Google Scholar]
  35. Mao, J.J.; He, C.T.; Pei, J.J.; Chen, W.X.; He, D.S.; He, Y.Q.; Zhuang, Z.B.; Chen, C.; Peng, Q.; Wang, D.S.; et al. Accelerating water dissociation kinetics by isolating cobalt atoms into ruthenium lattice. Nat. Commun. 2018, 9, 4958. [Google Scholar] [CrossRef]
Molecules 28 01100 g001 550
Figure 1. SEM images of (a) TaS3 NBs, (b)Ta3N5 NBs, (c) 5 wt% Ru/Ta3N5 NBs, and (d) 5 wt% Ru/TaS3 NBs; (e) XRD patterns of TaS3 NBs, Ta3N5 NBs, and 5 wt% Ru/Ta3N5 NBs (* and # are unknown peaks); (f) EDX spectrum of 5 wt% Ru/Ta3N5 NBs (inset: chemical components).
Figure 1. SEM images of (a) TaS3 NBs, (b)Ta3N5 NBs, (c) 5 wt% Ru/Ta3N5 NBs, and (d) 5 wt% Ru/TaS3 NBs; (e) XRD patterns of TaS3 NBs, Ta3N5 NBs, and 5 wt% Ru/Ta3N5 NBs (* and # are unknown peaks); (f) EDX spectrum of 5 wt% Ru/Ta3N5 NBs (inset: chemical components).
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Figure 2. (a,b) HRTEM images of 5 wt% Ru/Ta3N5 NBs.
Figure 2. (a,b) HRTEM images of 5 wt% Ru/Ta3N5 NBs.
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Figure 3. SEM images of (a) 1 wt% Ru/Ta3N5 NBs, (b) 3 wt% Ru/Ta3N5 NBs, (c) 7 wt% Ru/Ta3N5 NBs, and (d) 10 wt% Ru/Ta3N5 NBs.
Figure 3. SEM images of (a) 1 wt% Ru/Ta3N5 NBs, (b) 3 wt% Ru/Ta3N5 NBs, (c) 7 wt% Ru/Ta3N5 NBs, and (d) 10 wt% Ru/Ta3N5 NBs.
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Figure 4. XPS spectra of Ta3N5, 5 wt% Ru/Ta3N5, and Ru. (a) Survey, (b) N 1s, (c) Ta 4f, and (d) Ru3d5/2.
Figure 4. XPS spectra of Ta3N5, 5 wt% Ru/Ta3N5, and Ru. (a) Survey, (b) N 1s, (c) Ta 4f, and (d) Ru3d5/2.
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Figure 5. (a) LSV and (b) Tafel curves of 5 wt% Ru/Ta3N5 NBs, Ta3N5 NBs, 5 wt% Ru/TaS3 NBs, and Ru (5 wt% Ru/C); (c) LSV and (d) Tafel curves of 1 wt%, 3 wt%, 5 wt%, 7 wt%, and 10 wt% Ru/Ta3N5 NBs; (e) ΔJ/−v curves of 5 wt% Ru/Ta3N5 NBs, Ta3N5 NBs, and 5 wt% Ru/TaS3 NBs; (f) ΔJ/2−v curves of 1 wt%, 3 wt%, 5 wt%, 7 wt%, and 10 wt% Ru/Ta3N5 NBs.
Figure 5. (a) LSV and (b) Tafel curves of 5 wt% Ru/Ta3N5 NBs, Ta3N5 NBs, 5 wt% Ru/TaS3 NBs, and Ru (5 wt% Ru/C); (c) LSV and (d) Tafel curves of 1 wt%, 3 wt%, 5 wt%, 7 wt%, and 10 wt% Ru/Ta3N5 NBs; (e) ΔJ/−v curves of 5 wt% Ru/Ta3N5 NBs, Ta3N5 NBs, and 5 wt% Ru/TaS3 NBs; (f) ΔJ/2−v curves of 1 wt%, 3 wt%, 5 wt%, 7 wt%, and 10 wt% Ru/Ta3N5 NBs.
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Figure 6. (a) EIS curves of 5 wt% Ru/Ta3N5 NBs, Ta3N5 NBs, 5 wt% Ru/TaS3 NBs, and Ru (5 wt% Ru/C); inset is equivalent circuit. (b) EIS curves of 1 wt%, 3 wt%, 5 wt%, 7 wt%, and 10 wt% Ru/Ta3N5 NBs. (c) Chronoamperometric curves of 5 wt% Ru/Ta3N5 NBs. (d) Hydrogen adsorption free energy (ΔGH*) on Ta3N5 (H is adsorbed on Ta3N5: Ta3N5−H), Ru (H is adsorbed on different site of Ru: Ru−H1 and Ru−H2), and Ru/Ta3N5 (H is adsorbed on different site of Ru/Ta3N5: Ta3N5−Ru−H1, Ta3N5−Ru−H2, and Ta3N5−Ru−H3).
Figure 6. (a) EIS curves of 5 wt% Ru/Ta3N5 NBs, Ta3N5 NBs, 5 wt% Ru/TaS3 NBs, and Ru (5 wt% Ru/C); inset is equivalent circuit. (b) EIS curves of 1 wt%, 3 wt%, 5 wt%, 7 wt%, and 10 wt% Ru/Ta3N5 NBs. (c) Chronoamperometric curves of 5 wt% Ru/Ta3N5 NBs. (d) Hydrogen adsorption free energy (ΔGH*) on Ta3N5 (H is adsorbed on Ta3N5: Ta3N5−H), Ru (H is adsorbed on different site of Ru: Ru−H1 and Ru−H2), and Ru/Ta3N5 (H is adsorbed on different site of Ru/Ta3N5: Ta3N5−Ru−H1, Ta3N5−Ru−H2, and Ta3N5−Ru−H3).
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Figure 7. H atom absorbed on various crystalline structures: (a) Ru−H1; (b) Ru−H2; (c) Ta3N5−H; (d) Ta3N5−Ru−H1; (e) Ta3N5−Ru−H3; (f) Ta3N5−Ru−H4. (H: gray white; Ru: pale green; N: blue; Ta: light gray).
Figure 7. H atom absorbed on various crystalline structures: (a) Ru−H1; (b) Ru−H2; (c) Ta3N5−H; (d) Ta3N5−Ru−H1; (e) Ta3N5−Ru−H3; (f) Ta3N5−Ru−H4. (H: gray white; Ru: pale green; N: blue; Ta: light gray).
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Table
Table 1. HER catalytic activity of Ru-loaded hybrids in alkaline electrolytes.
Table 1. HER catalytic activity of Ru-loaded hybrids in alkaline electrolytes.
CatalystsElectrolytesOverpotential at 10 mAcm−2 (mV)Tafel Slope (mVdec−1)Stability (10 mAcm−2) Ref.
Ru/Ta3N5 NBs (Ru: 5 wt%)1.0 M KOH64.684.92Stability in 24 hThis work
Ru-NMCNs-500 1
(Ru: 3.04 wt%)		1.0 M KOH2835.2Increase of 28 mV after 10,000 cycles[20]
Ru/MoO2/C 21.0 M KOH1632Stability in 40 h[21]
Ru-Co@N-Graphene (Ru:3.58 wt%)1.0 M KOH2831Stability in 10,000 cycles[23]
B-Ru@CNT (Ru:9.2 wt%; B: 0.06 wt%)1.0 M KOH173085% of initial current after 15 h[24]
Ru/CeO2 (Ru:3 wt%)1.0 M KOH28.953.2Stability in 18 h[25]
1 Ru single-atom-loading, nitrogen-doped, mesoporous carbon nanospheres annealing at 500 °C; 2 Ru: MoO2: C is 21.25 wt%: 44.0 wt%: 34.74 wt%.
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Zhang, X.; Xu, L.; Wu, X.; Tao, Y.; Xiong, W. Ta3N5 Nanobelt-Loaded Ru Nanoparticle Hybrids’ Electrocatalysis for Hydrogen Evolution in Alkaline Media. Molecules 2023, 28, 1100. https://doi.org/10.3390/molecules28031100

AMA Style

Zhang X, Xu L, Wu X, Tao Y, Xiong W. Ta3N5 Nanobelt-Loaded Ru Nanoparticle Hybrids’ Electrocatalysis for Hydrogen Evolution in Alkaline Media. Molecules. 2023; 28(3):1100. https://doi.org/10.3390/molecules28031100

Chicago/Turabian Style

Zhang, Xinyu, Lulu Xu, Xingcai Wu, Yourong Tao, and Weiwei Xiong. 2023. "Ta3N5 Nanobelt-Loaded Ru Nanoparticle Hybrids’ Electrocatalysis for Hydrogen Evolution in Alkaline Media" Molecules 28, no. 3: 1100. https://doi.org/10.3390/molecules28031100

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