Next Article in Journal
Evaluation of Optical and Acoustical Properties of Ba1−xSrxTiO3 Thin Film Material Library via Conjugation of Picosecond Laser Ultrasonics with X-ray Diffraction, Energy Dispersive Spectroscopy, Electron Probe Micro Analysis, Scanning Electron and Atomic Force Microscopies
Previous Article in Journal
Mechanism of Amyloid Gel Formation by Several Short Amyloidogenic Peptides
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Nanomaterials
Volume 11
Issue 11
10.3390/nano11113130
nanomaterials-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles thumb_up
...
Endorse textsms
...
Comment
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Peroxymonosulfate Activation by Bi2WO6/BiOCl Heterojunction Nanocomposites under Visible Light for Bisphenol A Degradation

by
Yongkui Huang
1,*,
Xiangyang Yin
2,
Pei He
1,
Shuangwu Kou
2,
Xiaoting Zhang
2,
Lei Wang
2 and
Peili Lu
2,*
1
Key Laboratory of Shale Gas Exploration, Ministry of Natural Resources, Chongqing Institute of Geology and Mineral Resources, Chongqing 401120, China
2
State Key Laboratory of Coal Mine Disaster Dynamics and Control, College of Environment and Ecology, Chongqing University, Chongqing 400044, China
*
Authors to whom correspondence should be addressed.
Nanomaterials 2021, 11(11), 3130; https://doi.org/10.3390/nano11113130
Submission received: 15 October 2021 / Revised: 7 November 2021 / Accepted: 17 November 2021 / Published: 20 November 2021
(This article belongs to the Section Environmental Nanoscience and Nanotechnology)
Browse Figures
Versions Notes

Abstract

:
The combination of peroxymonosulfate (PMS) activation and photocatalysis has proven to be effective for organic contaminants treatment. However, the construction of an efficient catalytic material is an important challenge. Herein, novel Bi2WO6/BiOCl heterojunction nanocomposites were successfully designed and fabricated using a facile and effective strategy for bisphenol A (BPA) photodegradation with PMS activation. The well-designed heterojunction with improvement of the contact area and interface microstructure was obtained through in situ growth of the Bi2WO6 on the surface of BiOCl. The Bi2WO6/BiOCl nanocomposites exhibit excellent catalytic performance in PMS activation for BPA degradation under visible light irradiation. A possible photocatalytic reaction mechanism was systematically revealed. The excellent catalytic performance is mainly attributed to the strong interaction between Bi2WO6 and BiOCl, resulting in an enhanced photoabsorption and a more efficient interfacial charge separation and transfer. This paper provides a novel strategy to design efficient catalytic materials for organic contaminants remediation with PMS activation.

1. Introduction

Peroxymonosulfate (PMS) activation processes have been recognized as promising methods for practical environmental remediation of emerging recalcitrant contaminants [1,2,3]. The SO4•− with superior oxidation ability and selectivity can efficiently degrade organic contaminants [1]. The metal ions, composites, and carbonaceous catalyst are frequently exploited to activate PMS [4,5]. However, concerns have been raised about the inevitable leaching of toxic metals and secondary contamination. The combination of PMS activation and photocatalyst has become a research focus because of their synergistic effect in the mineralization of organic contaminants [6,7]. Unfortunately, the main challenge faced by this technology is the lack of a highly efficient catalytic material [8,9]. Therefore, exploring efficient and environmentally benign materials for PMS activation is highly desirable.
In recent decades, Bi-based materials have attracted increasing interest in the areas of photocatalytic applications [10]. In particular, bismuth oxychloride (BiOCl) has attracted significant interest due to its unique crystallographic structure, which can establish an internal electric field for interlayer charge transfer [11,12]. However, the catalytic performance of BiOCl is restricted by the poor photogenerated charge separation ability and inactiveness of visible light utilization, which reduces the overall efficiency [13,14]. Therefore, various strategies, such as surface modification, defect engineering, morphology control, and heterojunction construction, have been widely adopted to tailor the photocatalytic activity of BiOCl [10,13]. The photocatalytic activity of BiOCl has been improved by these modification methods to some extent, but BiOCl-based catalysts are still unsatisfactory for environmental applications.
The light response and charge separation are two important factors to improve photocatalytic activity of semiconductors [15,16]. The construction of heterojunction composites has been studied in order to enhance the light absorption, the charge separation efficiency, and the lifetime of carriers [10,17]. Up to now, various BiOCl-based composites have been developed on the basis of this fundamental mechanism, such as BiOCl/g-C3N4 [14], BiOCl/Bi24O31Cl10 [18], and NiO/BiOCl [19]. It is well known that the heterojunction effect is established by an electronic coupling effect produced from the interfacial interactions of two components to enhance light-responsive capability and expedite interfacial charge carrier mobility [10,20]. However, the conventional large-sized materials could not construct perfect heterojunction interfaces. Recently, interface engineering has often been applied to explore the design of heterostructures [21,22]. The preparation process of a specific heterojunction is expensive and complicated in the context of mass production [23,24,25]. Therefore, exploring a facile strategy to create efficient heterojunction photocatalysts is highly challenging and appealing.
Herein, we have successfully designed a facile route to build Bi2WO6/BiOCl heterojunctions for organic pollutants degradation with PMS activation. The well-designed heterojunction with improvement of the contact area and interface microstructure was obtained through the growth of Bi2WO6 on the surface of BiOCl nanoplates, which showed extremely high levels of photocatalytic activity and stability in bisphenol A (BPA) degradation with PMS activation. Furthermore, the possible reaction mechanism was revealed by radical trapping experiments, charge transportation, and band structures. These findings provide an efficient approach to design novel heterojunction materials for organic contaminants remediation.

2. Experimental Section

2.1. Preparation of Materials

The BiOCl nanoplate was constructed via a hydrothermal method. In general, 2 mmol of cetyltrimethylammonium chloride (CTAC) was added to 20 mL of deionized water, and added into 2 mmol of Bi(NO3)3•6H2O aqueous solution (40 mL) drop by drop. After 2 h of stirring, the resulting solution was poured into a 100 mL Teflon-lined autoclave and treated at 120 °C for 12 h. Then, the samples were washed several times with ultrapure water.
The Bi2WO6/BiOCl heterojunction was constructed by in situ growth strategy. Briefly, 0.26 g of BiOCl nanoplate dispersed ultrasonically in 60 mL of water for 1 h. A certain amount of Na2WO4·2H2O was added into the suspension. After being stirred for another 2 h, the suspension were poured into a 100 mL Teflon-lined autoclave and treated at 120 °C for 12 h. The precipitation was obtained after being washed with ultrapure water.
A series of Bi2WO6/BiOCl heterojunctions with different weight percentages of Bi2WO6 (13%, 25%, 47%, and 75%) were prepared under the identical experimental conditions and denoted as BC-1, BC-2, BC-3, and BC-4, respectively. Pure Bi2WO6 was also fabricated through the same process with Bi(NO3)3•6H2O instead of BiOCl.

2.2. Materials Characterization

The X-ray powder diffraction (XRD) patterns were carried out by PANalytical powder X-ray diffractometer. Raman spectra of the samples were obtained on LabRAM HR Raman spectroscopy (HORIBA, Longjumeau, France). Field-emission scanning electron microscopy (FE-SEM) images were recorded by a JSM-7800F microscope (Tokyo, Japan). The transmission electron microscope (TEM) and EDX spectrometry were collected with a Talos F200S microscope (Thermo Fisher Scientific, Waltham, MA, USA). X-ray photoelectron spectroscopy (XPS) were collected with a photoelectron spectroscope (Thermo Fisher Escalab 250Xi, Waltham, MA, USA). The UV-vis diffuse reflectance spectroscopy spectra (UV-vis DRS) were obtained with a Shimadzu UV-3600 spectrophotometer (Shimadzu, Kyoto, Japan). The N2 adsorption–desorption measurement was measured using ASAP 2020 (Micromeritics Instrument Corp, Norcross, GA, USA). The time-resolved fluorescence decay spectra and photoluminescence (TRPL) spectra was tested by FLS-920 fluorescence spectrometer (Edinburgh Instruments, Edinburgh, UK). The electrochemical impedance spectroscopy (EIS), photocurrent response, and Mott–Schottky curves were tested on a CHI-660E electrochemical workstation (CH Instruments, Shanghai, China) with Ag/AgCl, Pt plate, and 0.5 M Na2SO4 aqueous solution as reference electrode, counter electrode, and electrolyte, respectively.

2.3. Activity Evaluation

The activity evaluation of samples was conducted through the photodegradation of BPA with PMS activation under irradiation by 300 W Xe lamp with a 400 nm cut-off filter. Briefly, 50 mg of the sample was dispersed into a BPA solution (50 mL, 10 mg/L) under stirring for 30 min in the dark. After adding a specific amount of PMS, the lamp was triggered. The concentration of PMS was 1 mmol/L. The BPA residual concentration was analyzed using high-performance liquid chromatography (Agilent 1260, Santa Clara, CA, USA) with a C-18 column and UV wavelength at 276 nm. The mobile phase was 70% methanol and 30% water, the flow rate was 1.0 mL/min.

3. Results and Discussion

3.1. Characterizations of Catalysts

Figure 1 presents the XRD patterns of the samples. The peaks of pure BiOCl are well assigned to the tetragonal phase (JCPDS no. 06-0249), implying the high purity of BiOCl nanoplates [13,14]. The peaks of Bi2WO6 are assigned to the orthorhombic phase (JCPDS No. 39-0256) [26,27]. The main peaks of the nanocomposites could be well assigned to the tetragonal BiOCl. The diffraction peaks of Bi2WO6 intensified with increasing mass content of Bi2WO6, evidencing the formation of the Bi2WO6 in the nanocomposites. These results confirm that Bi2WO6/BiOCl nanocomposites were successfully prepared.
Figure 2 shows the Raman spectra of samples. The pure BiOCl nanoplates exhibited the two peaks at 144 and 199.8 cm−1 due to the Bi-Cl stretching mode in BiOCl [12,28]. For pure Bi2WO6, the strong peak at 309 cm−1 is associated with the translational modes of Bi3+ and WO66−. A weak peak centered at 410 cm−1 is assigned to WO6 bending (Eu) modes [29,30]. The broad band at 721 cm−1 is mainly assigned to the asymmetric stretching vibration of W plane and O [23,31]. The peaks at 798 and 824 cm−1 are associated with antisymmetric and symmetric Ag modes of O-W-O, respectively [23,29,30]. The characteristic peaks of Bi2WO6 and BiOCl are both shown in the spectra of the nanocomposites. Furthermore, the peaks intensity of Bi2WO6 gradually increased with increasing content of Bi2WO6, evidencing the presence of Bi2WO6 in the nanocomposites. The results explicitly confirm that the coexistence of BiOCl nanoplates and Bi2WO6 in the nanocomposites.
The morphology of the samples was observed using FE-SEM. As shown in Figure 3a, pure BiOCl nanoplates displayed an ultrathin plate structure with a size ranging from 500 nm~2 μm. The high-magnification SEM image (Figure 3b) reveals the plate had a smooth surface with thickness of about 20 nm. Furthermore, BC-3 nanocomposite preserved a wrinkled plate structure assembled from ultrathin nanosheets (Figure 3c). Figure 3d clearly shows that the surfaces of the plates became rough, which can be ascribed to the growth of Bi2WO6 on the surface of BiOCl. This result reveals that Bi2WO6 has been successfully grown on the surface of BiOCl.
The TEM and HRTEM images of the BC-3 nanocomposite are shown in Figure 4. An ultrathin plate morphology of the BC-3 nanocomposite can be clearly observed from Figure 4a,b. The HRTEM image (Figure 4c) clearly reveals the clear lattice fringes. The lattice spacing was confirmed to be 0.272 nm, corresponding to (2 0 0) plane of orthorhombic Bi2WO6 [32,33]. Moreover, the elemental mapping (Figure 4d) and EDX spectrum (Figure 4e) present the uniform distribution of Bi, O, Cl, and W elements in the nanocomposite. Those observations explicitly demonstrate that the in situ growth method resulted in a strong interfacial contact and a large contact area between the Bi2WO6 and BiOCl.
The XPS spectra of the samples are illustrated in Figure 5. As exhibited in Figure 5a, the survey scan spectra indicate that BC-3 nanocomposites are mainly composed of Bi, O, Cl, and W elements. From the Bi 4f spectra of pure BiOCl (Figure 5b), the peaks of Bi 4f5/2 and Bi 4f7/2 at 164.9 and 159.6 eV indicate bismuth existed in the form of Bi3+, respectively [13,34]. Notably, the Bi 4f7/2 and Bi 4f5/2 in the BC-3 nanocomposites were located at about 164.6 and159.3 eV, respectively [35,36]. These shifts can be attributed to the chemical bonding actions among the components. The Cl 2p3/2 and Cl 2p1/2 in BiOCl (Figure 5c) were located at 198.2 and 199.9 eV, which are characteristic positions of the Cl− [11,28]. These peaks changed to 198.0 and 199.7 eV after the construction of the Bi2WO6/BiOCl heterojunction, respectively. The XPS spectrum of O 1s in BiOCl (Figure 5d) displayed peaks at 531.0 and 530.1 eV, attributed to the lattice and surface oxygen [35,37,38]. Additionally, the O 1s spectrum of BC-3 nanocomposite was divided into three peaks at 531.0, 530.1, and 529.8 eV, corresponding to Bi-O, W-O, and hydroxyl groups, respectively [30,34]. From W 4f spectrum of BC-3 nanocomposite (Figure 5e), the peaks of W 4f at 37.5 and 35.4 eV are characteristic of the W6+ cations in Bi2WO6 [39,40]. The results indicate a strong interfacial contact between BiOCl and Bi2WO6 in Bi2WO6/BiOCl nanocomposites.
The UV-vis DRS of the samples is displayed in Figure 6a. The pure BiOCl exhibited a strong absorption in UV light regions and an absorption edge of around 370 nm, consistent with the literature reports [28,41]. Obviously, pure Bi2WO6 has an absorption edge of around 460 nm [42,43]. The Bi2WO6/BiOCl nanocomposites presented clear visible light absorption. Moreover, the absorption intensity gradually enhanced with increasing Bi2WO6 content. Furthermore, the band gap energy of the samples was studied (Figure 6b) [18,30]. The band gap energy values of pure BiOCl, Bi2WO6, BC-1, BC-2, BC-3, and BC-4 were 3.31, 2.66, 2.74, 2.68, and 2.62 eV, respectively, which demonstrates that the band gap energy of Bi2WO6/BiOCl nanocomposite decreased with the increasing content of Bi2WO6. These results demonstrate that a strong interface interaction between BiOCl and Bi2WO6 in the nanocomposites is effective to improve the visible light response.

3.2. Photocatalytic Activity Evaluation

The catalytic properties of the samples were examined by BPA degradation with PMS activation. Figure 7 shows the variations in BPA concentrations under various systems. The control experiment revealed that PMS could hardly degrade the BPA molecule. The removal rates of BPA were approximately 31.1% and 41.4% by the pure BiOCl and Bi2WO6 with PMS activation under visible light irradiation, respectively. As exhibited, the removal rate of BPA reached 97.4% by BC-3 under the same condition. Obviously, the removal rate of about 10.1% demonstrates that BC-3 cannot activate the PMS molecule without light irradiation. These results suggest that BC-3 exhibits an enhancement performance in BPA degradation with PMS activation under visible light irradiation.
Furthermore, the effects of Bi2WO6 in the Bi2WO6/BiOCl nanocomposite on the BPA degradation with PMS activation were investigated, and the results are shown in Figure 8. As the content of Bi2WO6 increased from 0 to 75.0%, the removal efficiency firstly increased and then decreased. Notably, the BC-3 nanocomposite showed the highest photocatalytic activity for PMS activation. This can be attributed to the successful construction heterojunctions between the Bi2WO6 and BiOCl, accelerating the charge separation. However, the excessive Bi2WO6 might decrease the interface effect. The kinetic behavior of the samples for BPA degradation was investigated. The reaction kinetics could be fitted well by the principle of kinetics pseudo first-order reaction [44,45]. The rate constants for BPA degradation by BiOCl, Bi2WO6, BC-1, BC-2, BC-3, and BC-4 with PMS activation were 0.010, 0.017, 0.024, 0.040, 0.102, and 0.044 min−1, respectively. So, the BC-3 displayed better photocatalytic activity than pure BiOCl and Bi2WO6, evidencing the synergistic effect between BiOCl and Bi2WO6. These results suggest that the content of Bi2WO6 is important to optimize the catalytic activities of the nanocomposites.
The stability and reusability of the catalysts are crucial for their practical applications [10,31]. Thus, the catalytic stability of the Bi2WO6/BiOCl nanocomposites was explored through the recycling reaction of BPA degradation. From Figure 9, a slight decrease in the catalytic activity of the BC-3 nanocomposite was observed after four cycles, illustrating that the nanocomposites have robust stability to activate PMS for BPA degradation and great potential in their practical application.

3.3. Photocatalytic Reaction Mechanisms

To explore the underlying mechanism, the active radical species generated in the photocatalytic process were tested by radical trapping experiments with benzoquinone (BQ), methanol (MeOH), isopropanol (IPA), and ethylenediamine tetraacetic acid disodium salt (EDTA) as radical scavengers, respectively [2,6,26]. Figure 10 shows that the degradation efficiency of BPA was slightly reduced with the addition of IPA, indicating that •OH has a negligible effect on BPA degradation. Furthermore, the degradation of BPA could be significantly limited by EDTA and BQ. Therefore, the holes (h+) and superoxide radical (•O2−) play pivotal roles in BPA degradation. Furthermore, the degradation of BPA was partially limited by methanol, which could be attributed to the rapid conversion of sulfate radicals. Therefore, the h+, SO4•−, and •O2− are important active radicals in the degradation process.
Generally, the specific surface area is a key factor influencing the catalytic ability of the catalyst [10,19]. Hence, N2 adsorption–desorption measurements were taken to reveal BET surface area and pore structure. The nitrogen sorption isotherms (Figure 11a) revealed that all the samples belonged to type IV isotherms with H3 loops, illustrating mesoporous structures [31,40]. The pore size distribution curves illustrate the coexistence of abundant mesopores and macropores (Figure 11b). The BC-3 nanocomposites showed larger specific surface area than pure BiOCl (5.394 m2/g), but lower than pure Bi2WO6 (Table 1). Therefore, the specific surface areas and pore size distributions are not the main reason for the enhanced photocatalytic performance of the samples.
The separation efficiency and kinetic barrier of Bi2WO6/BiOCl were revealed by EIS and photocurrent response. Sensitive and reproducible photocurrent responses of the sample under on/off visible light irradiation can be observed from Figure 12a. The BC-3 nanocomposite had higher photocurrent responses than pure BiOCl and Bi2WO6, illustrating an efficient charge transmission [30,42]. Furthermore, Figure 12b shows that the arc radius of the BC-3 nanocomposite was smaller than pure BiOCl and Bi2WO6, which suggests a lower charge transfer resistance [16,31]. Thus, the heterojunction interface between BiOCl and Bi2WO6 could provide a driving force for charge separation and transfer.
The TRPL spectra was used to further identify the charge transfer dynamics. As depicted in Figure 13, the curves are fitted well based on a two exponential decay function [25,31,46]. The average PL lifetimes of pure BiOCl, Bi2WO6, and BC-3 nanocomposite were calculated to be 1.44, 1.18, and 1.62 ns, respectively. Obviously, the average lifetimes of BC-3 nanocomposites are longer than those of pure BiOCl and Bi2WO6, which further indicates the most efficient migration of photoexcited charges [25,31]. As a result, a notable synergetic effect between BiOCl and Bi2WO6 can optimize the electronic structure and suppress the recombination of charge carriers, thus promoting the catalytic performance.
The Mott–Schottky plots of the samples are shown in Figure 14. The flat-band potential (Efb) could be determined based on the Mott–Schottky curves [16,47]. The positive slope of the curves suggests that the BiOCl and Bi2WO6 are n-type semiconductor. Notably, the Efb values of BiOCl and Bi2WO6 were determined to be −0.47 and −0.98 V (vs. Ag/AgCl), respectively. Therefore, the CB potential values of the BiOCl and Bi2WO6 were −0.25 and −0.76 V (vs. NHE, pH = 7), respectively [23,31]. Based on these results, the valence band (VB) positions were determined to be 3.06 and 1.90 V. These results indicate that the construction of a heterostructure interface between the BiOCl and Bi2WO6 can significantly improve photoinduced carrier separation efficiency and photocatalytic efficiency due to the matching energy levels.
Based on the above analysis, the possible mechanism for BPA degradation is portrayed in Figure 15. The heterojunction structure is obtained at the interface between BiOCl and Bi2WO6. Under light irradiation, Bi2WO6 is excited to form electrons and h+ [38,43]. The photogenerated electrons flow to the heterojunction interface, then to the CB of the BiOCl. The accumulation of electrons at the CB of the BiOCl reduce O2 and PMS in the solution to generate •O2− and SO4•− radicals [5,48]. Meanwhile, the generated h+ in the VB of BiOCl can easily accumulate at the surface of Bi2WO6 to directly degrade organic pollutants [40]. The •OH cannot be produced by h+ in the VB of Bi2WO6 due to its low oxidizing capacity, whereas a small amount of •OH is formed by the contribution of •O2− or PMS [26,42]. This result agrees well with the reactive species trapping experiments.

4. Conclusions

In summary, novel Bi2WO6/BiOCl heterojunction nanocomposites were successfully designed and fabricated by a facile and effective strategy. The heterojunction was fabricated by in situ growth of Bi2WO6 on the surface of BiOCl. The Bi2WO6/BiOCl nanocomposites possess excellent performance in PMS activation for BPA degradation under visible light irradiation. The Bi2WO6/BiOCl composite with 75.0% of Bi2WO6 exhibited the optimal catalytic performance. A possible photocatalytic mechanism for BPA degradation with PMS activation over Bi2WO6/BiOCl nanocomposites was systematically investigated. The improved catalytic performance of the Bi2WO6/BiOCl is attributed to the strong interaction between the Bi2WO6 and BiOCl, resulting in an enhanced photoabsorption and a more efficient charge interfacial separation and transfer. This work might provide new inspiration for designing efficient composites for the environmental remediation of organic contaminants.

Author Contributions

Conceptualization, Y.H. and P.L.; investigation, X.Y., S.K., and P.H.; writing—original draft preparation, Y.H. and X.Z.; writing—review and editing, X.Z., L.W., and P.H.; supervision, Y.H. and P.L.; funding acquisition, Y.H., P.L., and P.H. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by Natural Science Foundation of China (51808067 and 52004047), Natural Science Foundation of Chongqing (cstc2021jcyj-msxmX1194 and cstc2020jcyj-msxmX0610), National Key Research and Development Program (2019YFC1805502), and State Key Laboratory of Coal Mine Disaster Dynamics and Control (2011DA105287-MS201806).

Data Availability Statement

Data is contained within the article.

Acknowledgments

The authors gratefully acknowledge analytical and testing center of Chongqing university for the instrumental support.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Lee, J.; von Gunten, U.; Kim, J.H. Persulfate-Based Advanced Oxidation: Critical Assessment of Opportunities and Roadblocks. Environ. Sci. Technol. 2020, 54, 3064–3081. [Google Scholar] [CrossRef] [PubMed]
  2. Zeng, Y.; Guo, N.; Xu, X.; Yu, Y.; Wang, Q.; Wang, N.; Han, X.; Yu, H. Degradation of bisphenol a using peroxymonosulfate activated by WO3@MoS2/Ag hollow nanotubes photocatalyst. Chemosphere 2019, 227, 589–597. [Google Scholar] [CrossRef]
  3. Deng, W.; Zhao, H.; Pan, F.; Feng, X.; Jung, B.; Abdel-Wahab, A.; Batchelor, B.; Li, Y. Visible-Light-Driven Photocatalytic Degradation of Organic Water Pollutants Promoted by Sulfite Addition. Environ. Sci. Technol. 2017, 51, 13372–13379. [Google Scholar] [CrossRef] [PubMed]
  4. Zhang, H.; Nengzi, L.C.; Wang, Z.; Zhang, X.; Li, B.; Cheng, X. Construction of Bi2O3/CuNiFe LDHs composite and its enhanced photocatalytic degradation of lomefloxacin with persulfate under simulated sunlight. J. Hazard. Mater. 2020, 383, 121236. [Google Scholar] [CrossRef] [PubMed]
  5. Wang, Q.; Cui, Y.; Huang, R.; Zhong, L.; Yan, P.; Zhang, S.; Zhao, Q.; Jiang, D.; Tang, A.; Yang, H. A heterogeneous Fenton reaction system of N-doped TiO2 anchored on sepiolite activates peroxymonosulfate under visible light irradiation. Chem. Eng. J. 2020, 383, 123142. [Google Scholar] [CrossRef]
  6. Li, R.; Huang, J.; Cai, M.; Huang, J.; Xie, Z.; Zhang, Q.; Liu, Y.; Liu, H.; Lv, W.; Liu, G. Activation of peroxymonosulfate by Fe doped g-C3N4/graphene under visible light irradiation for Trimethoprim degradation. J. Hazard. Mater. 2020, 384, 121435. [Google Scholar] [CrossRef] [PubMed]
  7. Zeng, L.; Li, S.; Li, X.; Li, J.; Fan, S.; Chen, X.; Yin, Z.; Tadé, M.; Liu, S. Visible-light-driven sonophotocatalysis and peroxymonosulfate activation over 3D urchin-like MoS2/C nanoparticles for accelerating levofloxacin elimination: Optimization and kinetic study. Chem. Eng. J. 2019, 378, 122039. [Google Scholar] [CrossRef]
  8. Lim, J.; Yang, Y.; Hoffmann, M.R. Activation of Peroxymonosulfate by Oxygen Vacancies-Enriched Cobalt-Doped Black TiO2 Nanotubes for the Removal of Organic Pollutants. Environ. Sci. Technol. 2019, 53, 6972–6980. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  9. Duan, X.; Kang, J.; Tian, W.; Zhang, H.; Ho, S.-H.; Zhu, Y.-A.; Ao, Z.; Sun, H.; Wang, S. Interfacial-engineered cobalt@carbon hybrids for synergistically boosted evolution of sulfate radicals toward green oxidation. Appl. Catal. B Environ. 2019, 256, 117795. [Google Scholar] [CrossRef]
  10. He, R.; Xu, D.; Cheng, B.; Yu, J.; Ho, W. Review on nanoscale Bi-based photocatalysts. Nanoscale Horiz. 2018, 3, 464–504. [Google Scholar] [CrossRef]
  11. Zhang, N.; Li, L.; Shao, Q.; Zhu, T.; Huang, X.; Xiao, X. Fe-Doped BiOCl Nanosheets with Light-Switchable Oxygen Vacancies for Photocatalytic Nitrogen Fixation. ACS Appl. Energy Mater. 2019, 2, 8394–8398. [Google Scholar] [CrossRef]
  12. Zhang, L.; Han, Z.; Wang, W.; Li, X.; Su, Y.; Jiang, D.; Lei, X.; Sun, S. Solar-Light-Driven Pure Water Splitting with Ultrathin BiOCl Nanosheets. Chemistry 2015, 21, 18089–18094. [Google Scholar] [CrossRef] [PubMed]
  13. Yang, Z.; Wang, D.; Zhang, Y.; Feng, Z.; Liu, L.; Wang, W. Photoreductive BiOCl Ultrathin Nanosheets for Highly Efficient Photocatalytic Color Switching. ACS Appl. Mater. Interfaces 2020, 12, 8604–8613. [Google Scholar] [CrossRef]
  14. Al Marzouqi, F.; Al Farsi, B.; Kuvarega, A.T.; Al Lawati, H.A.J.; Al Kindy, S.M.Z.; Kim, Y.; Selvaraj, R. Controlled Microwave-Assisted Synthesis of the 2D-BiOCl/2D-g-C3N4 Heterostructure for the Degradation of Amine-Based Pharmaceuticals under Solar Light Illumination. ACS Omega 2019, 4, 4671–4678. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  15. Li, S.; Miao, P.; Zhang, Y.; Wu, J.; Zhang, B.; Du, Y.; Han, X.; Sun, J.; Xu, P. Recent Advances in Plasmonic Nanostructures for Enhanced Photocatalysis and Electrocatalysis. Adv. Mater. 2021, 33, e2000086. [Google Scholar] [CrossRef]
  16. Zhang, L.; Ran, J.; Qiao, S.Z.; Jaroniec, M. Characterization of semiconductor photocatalysts. Chem. Soc. Rev. 2019, 48, 5184–5206. [Google Scholar] [CrossRef]
  17. Yang, M.Q.; Gao, M.; Hong, M.; Ho, G.W. Visible-to-NIR Photon Harvesting: Progressive Engineering of Catalysts for Solar-Powered Environmental Purification and Fuel Production. Adv. Mater. 2018, 30, e1802894. [Google Scholar] [CrossRef] [PubMed]
  18. Li, F.-T.; Wang, Q.; Wang, X.-J.; Li, B.; Hao, Y.-J.; Liu, R.-H.; Zhao, D.-S. In-situ one-step synthesis of novel BiOCl/Bi24O31Cl10 heterojunctions via self-combustion of ionic liquid with enhanced visible-light photocatalytic activities. Appl. Catal. B Environ. 2014, 150–151, 574–584. [Google Scholar] [CrossRef]
  19. Sun, X.G.; Zhang, Y.Y.; Li, P.; Guo, D.; Zi, H.; Guo, J.Z.; Li, Y.T. Heterostructure nano-NiO/BiOCl composites with advanced adsorption and photocatalytic performance for organic dyes. J. Alloys Compd. 2018, 736, 22–28. [Google Scholar] [CrossRef]
  20. Waiskopf, N.; Ben-Shahar, Y.; Banin, U. Photocatalytic Hybrid Semiconductor-Metal Nanoparticles; from Synergistic Properties to Emerging Applications. Adv. Mater. 2018, 30, e1706697. [Google Scholar] [CrossRef] [PubMed]
  21. Feng, R.; Lei, W.; Liu, G.; Liu, M. Visible- and NIR-Light Responsive Black-Phosphorus-Based Nanostructures in Solar Fuel Production and Environmental Remediation. Adv. Mater. 2018, 30, e1804770. [Google Scholar] [CrossRef]
  22. Chen, S.; Takata, T.; Domen, K. Particulate photocatalysts for overall water splitting. Nat. Rev. Mater. 2017, 2, 17050. [Google Scholar] [CrossRef]
  23. Xing, Z.; Hu, J.; Ma, M.; Lin, H.; An, Y.; Liu, Z.; Zhang, Y.; Li, J.; Yang, S. From One to Two: In Situ Construction of an Ultrathin 2D-2D Closely Bonded Heterojunction from a Single-Phase Monolayer Nanosheet. J. Am. Chem. Soc. 2019, 141, 19715–19727. [Google Scholar] [CrossRef] [PubMed]
  24. Sun, J.; Tu, W.; Chen, C.; Plewa, A.; Ye, H.; Sam Oh, J.A.; He, L.; Wu, T.; Zeng, K.; Lu, L. Chemical Bonding Construction of Reduced Graphene Oxide-Anchored Few-Layer Bismuth Oxychloride for Synergistically Improving Sodium-Ion Storage. Chem. Mater. 2019, 31, 7311–7319. [Google Scholar] [CrossRef]
  25. Cao, X.; Chen, Z.; Lin, R.; Cheong, W.-C.; Liu, S.; Zhang, J.; Peng, Q.; Chen, C.; Han, T.; Tong, X.; et al. A photochromic composite with enhanced carrier separation for the photocatalytic activation of benzylic C–H bonds in toluene. Nat. Catal. 2018, 1, 704–710. [Google Scholar] [CrossRef]
  26. Huang, Y.; Kou, S.; Zhang, X.; Wang, L.; Lu, P.; Zhang, D. Facile Fabrication of Z-Scheme Bi2WO6/WO3 Composites for Efficient Photodegradation of Bisphenol A with Peroxymonosulfate Activation. Nanomaterials 2020, 10, 724. [Google Scholar] [CrossRef] [Green Version]
  27. Huang, Y.; Kang, S.; Yang, Y.; Qin, H.; Ni, Z.; Yang, S.; Li, X. Facile synthesis of Bi/Bi2WO6 nanocomposite with enhanced photocatalytic activity under visible light. Appl. Catal. B Environ. 2016, 196, 89–99. [Google Scholar] [CrossRef]
  28. Mi, Y.; Wen, L.; Wang, Z.; Cao, D.; Xu, R.; Fang, Y.; Zhou, Y.; Lei, Y. Fe(III) modified BiOCl ultrathin nanosheet towards high-efficient visible-light photocatalyst. Nano Energy 2016, 30, 109–117. [Google Scholar] [CrossRef]
  29. Huang, Y.; Kou, S.; Zhang, X.; Wang, L.; Zhang, D. In-situ construction of WC/Bi2WO6 nanocomposites for efficient photodegradation of bisphenol A with peroxymonosulfate activation. Ceram. Int. 2021, 47, 20626–20637. [Google Scholar] [CrossRef]
  30. Zhou, H.; Wen, Z.; Liu, J.; Ke, J.; Duan, X.; Wang, S. Z-scheme plasmonic Ag decorated WO3/Bi2WO6 hybrids for enhanced photocatalytic abatement of chlorinated-VOCs under solar light irradiation. Appl. Catal. B Environ. 2019, 242, 76–84. [Google Scholar] [CrossRef]
  31. Cao, S.; Shen, B.; Tong, T.; Fu, J.; Yu, J. 2D/2D Heterojunction of Ultrathin MXene/Bi2WO6 Nanosheets for Improved Photocatalytic CO2 Reduction. Adv. Funct. Mater. 2018, 28, 1800136. [Google Scholar] [CrossRef]
  32. Huang, H.; Cao, R.; Yu, S.; Xu, K.; Hao, W.; Wang, Y.; Dong, F.; Zhang, T.; Zhang, Y. Single-unit-cell layer established Bi2WO6 3D hierarchical architectures: Efficient adsorption, photocatalysis and dye-sensitized photoelectrochemical performance. Appl. Catal. B Environ. 2017, 219, 526–537. [Google Scholar] [CrossRef]
  33. Zhang, L.; Wang, W.; Chen, Z.; Zhou, L.; Xu, H.; Zhu, W. Fabrication of flower-like Bi2WO6 superstructures as high performance visible-light driven photocatalysts. J. Mater. Chem. 2007, 17, 2526–2532. [Google Scholar] [CrossRef]
  34. Wang, J.; Wei, Y.; Yang, B.; Wang, B.; Chen, J.; Jing, H. In situ grown heterojunction of Bi2WO6/BiOCl for efficient photoelectrocatalytic CO2 reduction. J. Catal. 2019, 377, 209–217. [Google Scholar] [CrossRef]
  35. Shiraishi, Y.; Hashimoto, M.; Chishiro, K.; Moriyama, K.; Tanaka, S.; Hirai, T. Photocatalytic Dinitrogen Fixation with Water on Bismuth Oxychloride in Chloride Solutions for Solar-to-Chemical Energy Conversion. J. Am. Chem. Soc. 2020, 142, 7574–7583. [Google Scholar] [CrossRef]
  36. Yao, H.; Li, H.; Hu, T.; Hou, W. Solvent-Free Synthesis of Bismuth Oxychloride Microflower/Nanosheet Homojunctions for Photoactivity Enhancement. ChemCatChem 2018, 10, 3726–3735. [Google Scholar] [CrossRef]
  37. Phu, N.D.; Hoang, L.H.; Van Hai, P.; Huy, T.Q.; Chen, X.-B.; Chou, W.C. Photocatalytic activity enhancement of Bi2WO6 nanoparticles by Ag doping and Ag nanoparticles modification. J. Alloys Compd. 2020, 824, 153914. [Google Scholar] [CrossRef]
  38. Li, Q.; Lu, M.; Wang, W.; Zhao, W.; Chen, G.; Shi, H. Fabrication of 2D/2D g-C3N4/Au/Bi2WO6 Z-scheme photocatalyst with enhanced visible-light-driven photocatalytic activity. Appl. Surf. Sci. 2020, 508, 144182. [Google Scholar] [CrossRef]
  39. Ma, Q.; Hu, X.; Liu, N.; Sharma, A.; Zhang, C.; Kawazoe, N.; Chen, G.; Yang, Y. Polyethylene glycol (PEG)-modified Ag/Ag2O/Ag3PO4/Bi2WO6 photocatalyst film with enhanced efficiency and stability under solar light. J. Colloid Interface Sci. 2020, 569, 101–113. [Google Scholar] [CrossRef] [PubMed]
  40. Sun, M.; Dong, X.; Lei, B.; Li, J.; Chen, P.; Zhang, Y.; Dong, F. Graphene oxide mediated co-generation of C-doping and oxygen defects in Bi2WO6 nanosheets: A combined DRIFTS and DFT investigation. Nanoscale 2019, 11, 20562–20570. [Google Scholar] [CrossRef]
  41. Armelao, L.; Bottaro, G.; Maccato, C.; Tondello, E. Bismuth oxychloride nanoflakes: Interplay between composition-structure and optical properties. Dalton. Trans. 2012, 41, 5480–5485. [Google Scholar] [CrossRef] [PubMed]
  42. Xia, J.X.; Di, J.; Yin, S.; Xu, H.; Zhang, J.; Xu, Y.G.; Xu, L.; Li, H.M.; Ji, M.X. Facile fabrication of the visible-light-driven Bi2WO6/BiOBr composite with enhanced photocatalytic activity. Rsc Adv. 2014, 4, 82–90. [Google Scholar] [CrossRef]
  43. Tian, Y.; Chang, B.; Lu, J.; Fu, J.; Xi, F.; Dong, X. Hydrothermal synthesis of graphitic carbon nitride-Bi2WO6 heterojunctions with enhanced visible light photocatalytic activities. ACS Appl. Mater. Interfaces 2013, 5, 7079–7085. [Google Scholar] [CrossRef]
  44. Wang, C.; Xue, Y.; Wang, P.F.; Ao, Y.H. Effects of water environmental factors on the photocatalytic degradation of sulfamethoxazole by AgI/UiO-66 composite under visible light irradiation. J. Alloys Compd. 2018, 748, 314–322. [Google Scholar] [CrossRef]
  45. Lee, C.G.; Javed, H.; Zhang, D.; Kim, J.H.; Westerhoff, P.; Li, Q.; Alvarez, P.J.J. Porous Electrospun Fibers Embedding TiO2 for Adsorption and Photocatalytic Degradation of Water Pollutants. Environ. Sci. Technol. 2018, 52, 4285–4293. [Google Scholar] [CrossRef]
  46. Huang, H.; Zhou, C.; Jiao, X.; Yuan, H.; Zhao, J.; He, C.; Hofkens, J.; Roeffaers, M.B.J.; Long, J.; Steele, J.A. Subsurface Defect Engineering in Single-Unit-Cell Bi2WO6 Monolayers Boosts Solar-Driven Photocatalytic Performance. ACS Catal. 2019, 10, 1439–1443. [Google Scholar] [CrossRef]
  47. Wang, T.; Liu, S.; Mao, W.; Bai, Y.; Chiang, K.; Shah, K.; Paz-Ferreiro, J. Novel Bi2WO6 loaded N-biochar composites with enhanced photocatalytic degradation of rhodamine B and Cr(VI). J. Hazard. Mater. 2020, 389, 121827. [Google Scholar] [CrossRef] [PubMed]
  48. Shao, H.; Zhao, X.; Wang, Y.; Mao, R.; Wang, Y.; Qiao, M.; Zhao, S.; Zhu, Y. Synergetic activation of peroxymonosulfate by Co3O4 modified g-C3N4 for enhanced degradation of diclofenac sodium under visible light irradiation. Appl. Catal. B Environ. 2017, 218, 810–818. [Google Scholar] [CrossRef]
Nanomaterials 11 03130 g001 550
Figure 1. XRD patterns of BiOCl, Bi2WO6, and Bi2WO6/BiOCl nanocomposites.
Figure 1. XRD patterns of BiOCl, Bi2WO6, and Bi2WO6/BiOCl nanocomposites.
Nanomaterials 11 03130 g001
Nanomaterials 11 03130 g002 550
Figure 2. Raman spectra of BiOCl, Bi2WO6, and Bi2WO6/BiOCl nanocomposites.
Figure 2. Raman spectra of BiOCl, Bi2WO6, and Bi2WO6/BiOCl nanocomposites.
Nanomaterials 11 03130 g002
Nanomaterials 11 03130 g003 550
Figure 3. FE-SEM images of pure BiOCl nanoplates (a,b) and BC-3 nanocomposite(c,d).
Figure 3. FE-SEM images of pure BiOCl nanoplates (a,b) and BC-3 nanocomposite(c,d).
Nanomaterials 11 03130 g003
Nanomaterials 11 03130 g004 550
Figure 4. TEM (a,b) and HRTEM (c) images, elemental mapping images (d) and EDS spectrum (e) of BC-3 nanocomposites.
Figure 4. TEM (a,b) and HRTEM (c) images, elemental mapping images (d) and EDS spectrum (e) of BC-3 nanocomposites.
Nanomaterials 11 03130 g004
Nanomaterials 11 03130 g005 550
Figure 5. XPS spectra of pure BiOCl, Bi2WO6, and BC-3: survey spectrum (a), Bi4f (b), Cl 2p (c), O 1s (d), and W 4f (e).
Figure 5. XPS spectra of pure BiOCl, Bi2WO6, and BC-3: survey spectrum (a), Bi4f (b), Cl 2p (c), O 1s (d), and W 4f (e).
Nanomaterials 11 03130 g005
Nanomaterials 11 03130 g006 550
Figure 6. UV-vis DRS (a) and Tauc plots (b) of pure BiOCl, Bi2WO6, and Bi2WO6/BiOCl nanocomposites.
Figure 6. UV-vis DRS (a) and Tauc plots (b) of pure BiOCl, Bi2WO6, and Bi2WO6/BiOCl nanocomposites.
Nanomaterials 11 03130 g006
Nanomaterials 11 03130 g007 550
Figure 7. Photocatalytic properties of BPA degradation using various systems. Reaction condition: initial BPA concentration of 10 mg/L, PMS dosage of 1 mmol/L, catalyst addition of 1 g/L.
Figure 7. Photocatalytic properties of BPA degradation using various systems. Reaction condition: initial BPA concentration of 10 mg/L, PMS dosage of 1 mmol/L, catalyst addition of 1 g/L.
Nanomaterials 11 03130 g007
Nanomaterials 11 03130 g008 550
Figure 8. Degradation curves of BPA with PMS activation over the Bi2WO6/BiOCl nanocomposites with various contents of Bi2WO6 (a) and the corresponding kinetics fitting curves (b). Reaction condition: initial BPA concentration of 10 mg/L, PMS dosage of 1 mmol/L, catalyst addition of 1 g/L.
Figure 8. Degradation curves of BPA with PMS activation over the Bi2WO6/BiOCl nanocomposites with various contents of Bi2WO6 (a) and the corresponding kinetics fitting curves (b). Reaction condition: initial BPA concentration of 10 mg/L, PMS dosage of 1 mmol/L, catalyst addition of 1 g/L.
Nanomaterials 11 03130 g008
Nanomaterials 11 03130 g009 550
Figure 9. The recycling test of the prepared nanocomposite. Reaction condition: initial BPA concentration of 10 mg/L, PMS dosage of 1 mmol/L, catalyst addition of 1 g/L.
Figure 9. The recycling test of the prepared nanocomposite. Reaction condition: initial BPA concentration of 10 mg/L, PMS dosage of 1 mmol/L, catalyst addition of 1 g/L.
Nanomaterials 11 03130 g009
Nanomaterials 11 03130 g010 550
Figure 10. The radical trapping experiment in the PMS activation by BC-3 nanocomposite for BPA degradation. Reaction condition: initial BPA concentration of 10 mg/L, PMS dosage of 1 mmol/L, catalyst addition of 1 g/L.
Figure 10. The radical trapping experiment in the PMS activation by BC-3 nanocomposite for BPA degradation. Reaction condition: initial BPA concentration of 10 mg/L, PMS dosage of 1 mmol/L, catalyst addition of 1 g/L.
Nanomaterials 11 03130 g010
Nanomaterials 11 03130 g011 550
Figure 11. N2 adsorption–desorption isotherm (a) and pore size distribution (b) of pure BiOCl, Bi2WO6, and BC-3 nanocomposite.
Figure 11. N2 adsorption–desorption isotherm (a) and pore size distribution (b) of pure BiOCl, Bi2WO6, and BC-3 nanocomposite.
Nanomaterials 11 03130 g011
Nanomaterials 11 03130 g012 550
Figure 12. The EIS (a) and photocurrent response (b) of pure BiOCl, Bi2WO6, and Bi2WO6/BiOCl nanocomposites.
Figure 12. The EIS (a) and photocurrent response (b) of pure BiOCl, Bi2WO6, and Bi2WO6/BiOCl nanocomposites.
Nanomaterials 11 03130 g012
Nanomaterials 11 03130 g013 550
Figure 13. The TRPL spectra of pure BiOCl, Bi2WO6, and Bi2WO6/BiOCl nanocomposites.
Figure 13. The TRPL spectra of pure BiOCl, Bi2WO6, and Bi2WO6/BiOCl nanocomposites.
Nanomaterials 11 03130 g013
Nanomaterials 11 03130 g014 550
Figure 14. Mott–Schottky curves of the pure BiOCl and Bi2WO6.
Figure 14. Mott–Schottky curves of the pure BiOCl and Bi2WO6.
Nanomaterials 11 03130 g014
Nanomaterials 11 03130 g015 550
Figure 15. A proposed mechanism for BPA degradation via Bi2WO6/BiOCl nanocomposites with PMS activation.
Figure 15. A proposed mechanism for BPA degradation via Bi2WO6/BiOCl nanocomposites with PMS activation.
Nanomaterials 11 03130 g015
Table
Table 1. The SBET and average pore size of pure BiOCl, Bi2WO6, and BC-3 nanocomposite.
Table 1. The SBET and average pore size of pure BiOCl, Bi2WO6, and BC-3 nanocomposite.
SampleSBET(m2∙g−1)Average Pore Size (nm)
BiOCl5.3943.292
Bi2WO646.2023.792
BC-316.1293.704
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Share and Cite

MDPI and ACS Style

Huang, Y.; Yin, X.; He, P.; Kou, S.; Zhang, X.; Wang, L.; Lu, P. Peroxymonosulfate Activation by Bi2WO6/BiOCl Heterojunction Nanocomposites under Visible Light for Bisphenol A Degradation. Nanomaterials 2021, 11, 3130. https://doi.org/10.3390/nano11113130

AMA Style

Huang Y, Yin X, He P, Kou S, Zhang X, Wang L, Lu P. Peroxymonosulfate Activation by Bi2WO6/BiOCl Heterojunction Nanocomposites under Visible Light for Bisphenol A Degradation. Nanomaterials. 2021; 11(11):3130. https://doi.org/10.3390/nano11113130

Chicago/Turabian Style

Huang, Yongkui, Xiangyang Yin, Pei He, Shuangwu Kou, Xiaoting Zhang, Lei Wang, and Peili Lu. 2021. "Peroxymonosulfate Activation by Bi2WO6/BiOCl Heterojunction Nanocomposites under Visible Light for Bisphenol A Degradation" Nanomaterials 11, no. 11: 3130. https://doi.org/10.3390/nano11113130

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