以Bi(NO3)3·5H2O、Na2WO4·2H2O、AgNO3为原料,利用液相沉淀法制备Bi2WO6及Ag掺杂Bi2WO6光催化剂,以亚甲基蓝溶液为目标降解物,对其降解效率进行研究。研究结果表明,当亚甲基蓝溶液的浓度为15 mg/L,体积为50 m L,降解时间3.5 h...以Bi(NO3)3·5H2O、Na2WO4·2H2O、AgNO3为原料,利用液相沉淀法制备Bi2WO6及Ag掺杂Bi2WO6光催化剂,以亚甲基蓝溶液为目标降解物,对其降解效率进行研究。研究结果表明,当亚甲基蓝溶液的浓度为15 mg/L,体积为50 m L,降解时间3.5 h,Bi2WO6降解率仅为55%;当Ag/Bi摩尔比为0.4%时,Ag/Bi2WO6表现出较好的催化性能,相同时间降解率达到97%。展开更多
The fabrication of multicomponent composite systems may provide bene ts in terms of charge separation and the retardation of charge pair recombination. In this work, a ternary heterostructured Ag-Bi2MoO6/BiPO4 composi...The fabrication of multicomponent composite systems may provide bene ts in terms of charge separation and the retardation of charge pair recombination. In this work, a ternary heterostructured Ag-Bi2MoO6/BiPO4 composite was fabricated through a low-temperature solution-phase route for the rst time. The XRD, SEM, EDX and XPS results indicated the prepared sample is a three-phase composite of BiPO4, Bi2MoO6, and Ag. Ag nanopar-ticles were photodeposited on the surface of Bi2MoO6/BiPO4 nanosheets, which not only increase visible-light absorption via the surface plasmon resonance, but also serve as good electron acceptor for facilitating quick photoexcited electron transfer. The interface between Bi2MoO6 and BiPO4 facilitates the migration of photoinduced electrons from Bi2MoO6 to BiPO4, which is also conductive to reduce the recombination of electron-holes. Thus, the ternary heterostructured Ag-Bi2MoO6/BiPO4 composite showed signi cant photocatalytic activity, higher than pure Bi2MoO6, BiPO4, and Bi2MoO6/BiPO4. Moreover, the possible photocatalytic mechanism of the Ag-Bi2MoO6/BiPO4 heterostructure related to the band positions of the semiconductors was also discussed. In addition, the quenching effects of di erent scavengers revealed that the reactive ·OH and O2·- play a major role in the phenol red decolorization.展开更多
Bismuth tungstate(Bi_(2)WO_(6))has become a research hotspot due to its potential in photocatalytic energy conversion and environmental purification.Nevertheless,the limited light absorption and fast recombination of ...Bismuth tungstate(Bi_(2)WO_(6))has become a research hotspot due to its potential in photocatalytic energy conversion and environmental purification.Nevertheless,the limited light absorption and fast recombination of photogenerated carriers hinder the further improvement of the photocatalytic performance of Bi_(2)WO_(6).Herein,we provide a systematic review for the recent advances on Bi_(2)WO_(6)‐based photocatalysts.It starts with the crystal structure,optical properties and photocatalytic fundamentals of Bi_(2)WO_(6).Then,we focus on the modification strategies of Bi_(2)WO_(6)based on morphology control,atomic modulation and composite fabrication for diverse photocatalytic applications,such as organic synthesis,water splitting,CO2 reduction,water treatment,air purification,bacterial inactivation,etc.Finally,some current challenges and future development prospects are proposed.We expect that this review can provide a useful reference and guidance for the development of efficient Bi_(2)WO_(6)photocatalysts.展开更多
Although the traditional Fenton reaction is considered an effective strategy for solving problems caused by environmental pollution,construction of an efficient photocatalytic system by coordinating the Fenton reactio...Although the traditional Fenton reaction is considered an effective strategy for solving problems caused by environmental pollution,construction of an efficient photocatalytic system by coordinating the Fenton reaction is challenging.In this study,2D/2D step-schemeα-Fe2O3/Bi2WO6(FO/BWO)heterostructure photo-Fenton catalysts were successfully fabricated by a facile hydrothermal method.The as-prepared materials were characterized by XRD,FT-IR,TEM,XPS,UV-vis DRS,PL,I-t,EIS,and BET analyses.Under visible light irradiation,FO/BWO exhibited remarkably high and stable photo-Fenton catalytic activity for the degradation of methyl blue(MB)at low concentrations of H2O2.It was noted that FO/BWO(0.5)displayed a significantly enhanced photo-Fenton catalytic activity,which was 11.06 and 3.29 times those of FO nanosheets and BWO nanosheets,respectively.The notably improved photo-Fenton catalytic activity of FO/BWO was mainly due to the combination of H2O2 and FO under light illumination and the presence of the 2D/2D S-scheme heterostructure,with the large contact surface,abundant active sites,and efficient separation rate of photogenerated carriers playing contributory roles.Additionally,a possible catalytic mechanism for the FO/BWO composite was preliminarily proposed via active species trapping experiments.In summary,this study provided new insights into the synthesis of an effectively heterogeneous 2D/2D S-scheme photo-Fenton catalyst for degradation of organic pollutants in wastewater.展开更多
Ag3PO4has good potential for use in photocatalytic degradation of organic contaminants.However,the activity and stability of Ag3PO4is hard to sustain because of photocorrosion and the positive potential of the conduct...Ag3PO4has good potential for use in photocatalytic degradation of organic contaminants.However,the activity and stability of Ag3PO4is hard to sustain because of photocorrosion and the positive potential of the conduction band of Ag3PO4.In this study,A composite consisting of Bi2WO6nanosheets and Ag3PO4was developed to curb recombination of charge carriers and enhance the activity and stability of the catalyst.Formation of a Ag3PO4/Bi2WO6composite was confirmed using X‐ray diffraction,energy‐dispersive X‐ray spectroscopy,and X‐ray photoelectron spectroscopy.Photoluminescence spectroscopy provided convincing evidence that compositing Bi2WO6with Ag3PO4effectively reduced photocorrosion of Ag3PO4.The Ag3PO4/Bi2WO6composite gave a high photocatalytic performance in photodegradation of methylene blue.A degradation rate of0.61min?1was achieved;this is1.3and6.0times higher than those achieved using Ag3PO4(0.47min?1)and Bi2WO6(0.10min?1),respectively.Reactive species trapping experiments using the Ag3PO4/Bi2WO6composite showed that holes,?OH,and?O2?all played specific roles in the photodegradation process.The photocatalytic mechanism was investigated and a Z‐scheme was proposed as a plausible mechanism.展开更多
The development of Bi2WO6-based materials has become one of research hotspots due to the increasing demands on high-efficient photocatalyst responding to visible light.In this work,the effect of high energy radiation(...The development of Bi2WO6-based materials has become one of research hotspots due to the increasing demands on high-efficient photocatalyst responding to visible light.In this work,the effect of high energy radiation(γ-ray)on the structure and the photocatalytic activity of Bi2WO6 nanocrystals was first studied.No morphological change of Bi2WO6 nanocrystals was observed by SEM underγ-ray radiation.However,the XRD spectra of the irradiated Bi2WO6 nanocrystals showed the characteristic 2θof(113)plane shifts slightly from 28.37o to 28.45o with the increase of the absorbed dose,confirming the change in the crystal structure of Bi2WO6.The XPS results proved the crystal structure change was originated from the generation of oxygen vacancy defects under high-dose radiation.The photocatalytic activity of Bi2WO6 on the decomposition of methylene blue(MB)in water under visible light increases gradually with the increase of absorbed dose.Moreover,the improved photocatalytic performance of the irradiated Bi2WO6 nanocrystals remained after three cycles of photocatalysis,indicating a good stability of the created oxygen vacancy defects.This work gives a new simple way to improve photocatalytic performance of Bi2WO6 through creating oxygen vacancy defects in the crystal structure by-ray radiation.展开更多
A type of visible light photocatalyst Bi2WO6 was prepared from Bi(NO3)3.5H2O and Na2WO4.2H2O by means of hydrothermal method and was characterized by UV-vis diffuse reflectance spectrometry and XRD.Oxidative desulfuri...A type of visible light photocatalyst Bi2WO6 was prepared from Bi(NO3)3.5H2O and Na2WO4.2H2O by means of hydrothermal method and was characterized by UV-vis diffuse reflectance spectrometry and XRD.Oxidative desulfurization via photocatalysis was investigated using thiophene dissolved in octane as the model compound,with hydrogen peroxide used as the oxidant.The effects of hydrogen peroxide mass fraction,irradiation time,dosage of photocatalyst Bi2WO6 on the desulfurization efficiency were also investigated.Under suitable conditions,the desulfurization rate of model compound reached over 70%.展开更多
文摘以Bi(NO3)3·5H2O、Na2WO4·2H2O、AgNO3为原料,利用液相沉淀法制备Bi2WO6及Ag掺杂Bi2WO6光催化剂,以亚甲基蓝溶液为目标降解物,对其降解效率进行研究。研究结果表明,当亚甲基蓝溶液的浓度为15 mg/L,体积为50 m L,降解时间3.5 h,Bi2WO6降解率仅为55%;当Ag/Bi摩尔比为0.4%时,Ag/Bi2WO6表现出较好的催化性能,相同时间降解率达到97%。
文摘The fabrication of multicomponent composite systems may provide bene ts in terms of charge separation and the retardation of charge pair recombination. In this work, a ternary heterostructured Ag-Bi2MoO6/BiPO4 composite was fabricated through a low-temperature solution-phase route for the rst time. The XRD, SEM, EDX and XPS results indicated the prepared sample is a three-phase composite of BiPO4, Bi2MoO6, and Ag. Ag nanopar-ticles were photodeposited on the surface of Bi2MoO6/BiPO4 nanosheets, which not only increase visible-light absorption via the surface plasmon resonance, but also serve as good electron acceptor for facilitating quick photoexcited electron transfer. The interface between Bi2MoO6 and BiPO4 facilitates the migration of photoinduced electrons from Bi2MoO6 to BiPO4, which is also conductive to reduce the recombination of electron-holes. Thus, the ternary heterostructured Ag-Bi2MoO6/BiPO4 composite showed signi cant photocatalytic activity, higher than pure Bi2MoO6, BiPO4, and Bi2MoO6/BiPO4. Moreover, the possible photocatalytic mechanism of the Ag-Bi2MoO6/BiPO4 heterostructure related to the band positions of the semiconductors was also discussed. In addition, the quenching effects of di erent scavengers revealed that the reactive ·OH and O2·- play a major role in the phenol red decolorization.
文摘Bismuth tungstate(Bi_(2)WO_(6))has become a research hotspot due to its potential in photocatalytic energy conversion and environmental purification.Nevertheless,the limited light absorption and fast recombination of photogenerated carriers hinder the further improvement of the photocatalytic performance of Bi_(2)WO_(6).Herein,we provide a systematic review for the recent advances on Bi_(2)WO_(6)‐based photocatalysts.It starts with the crystal structure,optical properties and photocatalytic fundamentals of Bi_(2)WO_(6).Then,we focus on the modification strategies of Bi_(2)WO_(6)based on morphology control,atomic modulation and composite fabrication for diverse photocatalytic applications,such as organic synthesis,water splitting,CO2 reduction,water treatment,air purification,bacterial inactivation,etc.Finally,some current challenges and future development prospects are proposed.We expect that this review can provide a useful reference and guidance for the development of efficient Bi_(2)WO_(6)photocatalysts.
文摘Although the traditional Fenton reaction is considered an effective strategy for solving problems caused by environmental pollution,construction of an efficient photocatalytic system by coordinating the Fenton reaction is challenging.In this study,2D/2D step-schemeα-Fe2O3/Bi2WO6(FO/BWO)heterostructure photo-Fenton catalysts were successfully fabricated by a facile hydrothermal method.The as-prepared materials were characterized by XRD,FT-IR,TEM,XPS,UV-vis DRS,PL,I-t,EIS,and BET analyses.Under visible light irradiation,FO/BWO exhibited remarkably high and stable photo-Fenton catalytic activity for the degradation of methyl blue(MB)at low concentrations of H2O2.It was noted that FO/BWO(0.5)displayed a significantly enhanced photo-Fenton catalytic activity,which was 11.06 and 3.29 times those of FO nanosheets and BWO nanosheets,respectively.The notably improved photo-Fenton catalytic activity of FO/BWO was mainly due to the combination of H2O2 and FO under light illumination and the presence of the 2D/2D S-scheme heterostructure,with the large contact surface,abundant active sites,and efficient separation rate of photogenerated carriers playing contributory roles.Additionally,a possible catalytic mechanism for the FO/BWO composite was preliminarily proposed via active species trapping experiments.In summary,this study provided new insights into the synthesis of an effectively heterogeneous 2D/2D S-scheme photo-Fenton catalyst for degradation of organic pollutants in wastewater.
基金supported by the National Natural Science Foundation of China(51572103,51502106)the Foundation for Young Talents in College of Anhui Province(gxyqZD201751)~~
文摘Ag3PO4has good potential for use in photocatalytic degradation of organic contaminants.However,the activity and stability of Ag3PO4is hard to sustain because of photocorrosion and the positive potential of the conduction band of Ag3PO4.In this study,A composite consisting of Bi2WO6nanosheets and Ag3PO4was developed to curb recombination of charge carriers and enhance the activity and stability of the catalyst.Formation of a Ag3PO4/Bi2WO6composite was confirmed using X‐ray diffraction,energy‐dispersive X‐ray spectroscopy,and X‐ray photoelectron spectroscopy.Photoluminescence spectroscopy provided convincing evidence that compositing Bi2WO6with Ag3PO4effectively reduced photocorrosion of Ag3PO4.The Ag3PO4/Bi2WO6composite gave a high photocatalytic performance in photodegradation of methylene blue.A degradation rate of0.61min?1was achieved;this is1.3and6.0times higher than those achieved using Ag3PO4(0.47min?1)and Bi2WO6(0.10min?1),respectively.Reactive species trapping experiments using the Ag3PO4/Bi2WO6composite showed that holes,?OH,and?O2?all played specific roles in the photodegradation process.The photocatalytic mechanism was investigated and a Z‐scheme was proposed as a plausible mechanism.
基金supported by the National Natural Science Foundation of China (No.51473152, No.51573174, and No.51773189)Science Challenge Project (No.TZ2018004)the Fundamental Research Funds for the Central Universities (WK3450000001 and WK3450000004)
文摘The development of Bi2WO6-based materials has become one of research hotspots due to the increasing demands on high-efficient photocatalyst responding to visible light.In this work,the effect of high energy radiation(γ-ray)on the structure and the photocatalytic activity of Bi2WO6 nanocrystals was first studied.No morphological change of Bi2WO6 nanocrystals was observed by SEM underγ-ray radiation.However,the XRD spectra of the irradiated Bi2WO6 nanocrystals showed the characteristic 2θof(113)plane shifts slightly from 28.37o to 28.45o with the increase of the absorbed dose,confirming the change in the crystal structure of Bi2WO6.The XPS results proved the crystal structure change was originated from the generation of oxygen vacancy defects under high-dose radiation.The photocatalytic activity of Bi2WO6 on the decomposition of methylene blue(MB)in water under visible light increases gradually with the increase of absorbed dose.Moreover,the improved photocatalytic performance of the irradiated Bi2WO6 nanocrystals remained after three cycles of photocatalysis,indicating a good stability of the created oxygen vacancy defects.This work gives a new simple way to improve photocatalytic performance of Bi2WO6 through creating oxygen vacancy defects in the crystal structure by-ray radiation.
基金support provided by the Shaanxi Provincial Education Project (09JK816)
文摘A type of visible light photocatalyst Bi2WO6 was prepared from Bi(NO3)3.5H2O and Na2WO4.2H2O by means of hydrothermal method and was characterized by UV-vis diffuse reflectance spectrometry and XRD.Oxidative desulfurization via photocatalysis was investigated using thiophene dissolved in octane as the model compound,with hydrogen peroxide used as the oxidant.The effects of hydrogen peroxide mass fraction,irradiation time,dosage of photocatalyst Bi2WO6 on the desulfurization efficiency were also investigated.Under suitable conditions,the desulfurization rate of model compound reached over 70%.
