以硝酸铋和氯化钾为原料,乙二醇为溶剂制备了BiOCl光催化剂。通过XRD,SEM和DRS对其结构、形貌和光吸收性能进行了表征。结果表明所得BiOCl为纯相四方晶系晶体,呈花球状,且带隙能为3.26 e V。以苯酚为目标物考察了BiOCl的光催化活性。在3...以硝酸铋和氯化钾为原料,乙二醇为溶剂制备了BiOCl光催化剂。通过XRD,SEM和DRS对其结构、形貌和光吸收性能进行了表征。结果表明所得BiOCl为纯相四方晶系晶体,呈花球状,且带隙能为3.26 e V。以苯酚为目标物考察了BiOCl的光催化活性。在365 nm单波长光照射600 min后,苯酚的降解率达到了75%,但其矿化率只达到14.8%。这表明苯酚特征衍射峰强度的消失并不表明其被完全矿化。通过质谱分析,对苯酚的光催化反应机理进行了初步探究。展开更多
CO2 photoreduction by semiconductors is of growing interest. Fabrication of oxygen-deficient surfaces is an important strategy for enhancing CO2 photoreduction activity. However, regeneration of the oxygen vacancies i...CO2 photoreduction by semiconductors is of growing interest. Fabrication of oxygen-deficient surfaces is an important strategy for enhancing CO2 photoreduction activity. However, regeneration of the oxygen vacancies in photocatalysts is still a problem since an oxygen vacancy will be filled up by the O atom from CO2 after the dissociation process. Herein, we have fabricated highly efficient BiOC1 nanoplates with photoinduced oxygen vacancies. Oxygen vacancies were easily regenerated by light irradiation due to the high oxygen atom density and low Bi~） bond energy even when the oxygen vacancies had been filled up by the O atom in the photocatalytic reactions. These oxygen vacancies not only enhanced the trapping capability for CO2, but also enhanced the efficiency of separation of electron-hole pairs, which resulted in the photocatalytic CO2 reduction under simulated solar light. Furthermore, the generation and recovery of the defects in the BiOC1 could be realized during the photocatalytic reduction of CO2 in water. The existence of photoinduced defects in thin BiOC1 nanoplates undoubtedly leads to new possibilities for the design of solar-driven bismuth based photocatalysts.展开更多
Photocatalytic technology holds great promise in renewable energy and environmental protection.Herein,we report the synthesis of a class of polyaniline-sensitized BiOCI core/shell nanosheets with visible-light photoca...Photocatalytic technology holds great promise in renewable energy and environmental protection.Herein,we report the synthesis of a class of polyaniline-sensitized BiOCI core/shell nanosheets with visible-light photocatalytic activity by a one-step oxidative polymerization method and show how the hybrid nanosheet boosts the photocatalytic activity and stability for degradation of Rhodamine B (RhB).In this unique structure,the ultrathin polyaniline (PANI)as a shell with the thickness of about 1-2nm,can widen the response of the catalyst to visible light to boost photocatalysis and the BiOCI core can promote the separation of photogenerated carriers from the PANI.We demonstrate that the optimized BiOCl/ PANI core/shell photocatalyst shows nearly three times higher photocatalytic activity for the degradation of RhB than pure BLOC1and also shows high stability.This work provides a new strategy for the design of a highly efficient hybrid photo- catalyst driven by visible light.展开更多
A facile and environment friendly approach to synthesis of unique hierarchical BiOCl flowery microspheres(FMs)using a biodegradable surfactant polyvinyl alcohol(PVA)was reported herein for the first time.Compared to t...A facile and environment friendly approach to synthesis of unique hierarchical BiOCl flowery microspheres(FMs)using a biodegradable surfactant polyvinyl alcohol(PVA)was reported herein for the first time.Compared to the BiOCl nanosheets synthesized in the absence of PVA,hierarchical BiOCl FMs consist of large amounts of interwoven polycrystalline nanosheets that assemble into a porous flowery structure.The formation mechanism of the hierarchical BiOCl FMs was also proposed,whereby PVA was believed to play a key role in the crystal growth and the formation of the final microstructures.Compared with TiO2-P25 and BiOCl nanosheets,hierarchical BiOCl FMs displayed remarkably enhanced photocatalytic activity,and20 mg of BiOCl FMs could completely degrade 50 mL of methyl orange solution(20 mg/L)within 30 min under UVlight irradiation.According to the comprehensive analysis,it can be concluded that the larger specific surface area,porosity,suitable band gap,and the enhanced light absorption capacity may contribute to the remarkably enhanced photocatalytic activity.This facile and green approach to fabricating hierarchical BiOCl FMs would give vital clues to develop new route for synthesizing other hierarchical structured materials.展开更多
文摘以硝酸铋和氯化钾为原料,乙二醇为溶剂制备了BiOCl光催化剂。通过XRD,SEM和DRS对其结构、形貌和光吸收性能进行了表征。结果表明所得BiOCl为纯相四方晶系晶体,呈花球状,且带隙能为3.26 e V。以苯酚为目标物考察了BiOCl的光催化活性。在365 nm单波长光照射600 min后,苯酚的降解率达到了75%,但其矿化率只达到14.8%。这表明苯酚特征衍射峰强度的消失并不表明其被完全矿化。通过质谱分析,对苯酚的光催化反应机理进行了初步探究。
文摘CO2 photoreduction by semiconductors is of growing interest. Fabrication of oxygen-deficient surfaces is an important strategy for enhancing CO2 photoreduction activity. However, regeneration of the oxygen vacancies in photocatalysts is still a problem since an oxygen vacancy will be filled up by the O atom from CO2 after the dissociation process. Herein, we have fabricated highly efficient BiOC1 nanoplates with photoinduced oxygen vacancies. Oxygen vacancies were easily regenerated by light irradiation due to the high oxygen atom density and low Bi~） bond energy even when the oxygen vacancies had been filled up by the O atom in the photocatalytic reactions. These oxygen vacancies not only enhanced the trapping capability for CO2, but also enhanced the efficiency of separation of electron-hole pairs, which resulted in the photocatalytic CO2 reduction under simulated solar light. Furthermore, the generation and recovery of the defects in the BiOC1 could be realized during the photocatalytic reduction of CO2 in water. The existence of photoinduced defects in thin BiOC1 nanoplates undoubtedly leads to new possibilities for the design of solar-driven bismuth based photocatalysts.
基金supported by the National Natural Science Foundation of China (51772255) Hunan Natural Science Foundation (2016JJ3123)+1 种基金 the National Key Research and Development Program of China (2016YFB0100201)the start-up supports from Peking University and Young Thousand Talented Program
文摘Photocatalytic technology holds great promise in renewable energy and environmental protection.Herein,we report the synthesis of a class of polyaniline-sensitized BiOCI core/shell nanosheets with visible-light photocatalytic activity by a one-step oxidative polymerization method and show how the hybrid nanosheet boosts the photocatalytic activity and stability for degradation of Rhodamine B (RhB).In this unique structure,the ultrathin polyaniline (PANI)as a shell with the thickness of about 1-2nm,can widen the response of the catalyst to visible light to boost photocatalysis and the BiOCI core can promote the separation of photogenerated carriers from the PANI.We demonstrate that the optimized BiOCl/ PANI core/shell photocatalyst shows nearly three times higher photocatalytic activity for the degradation of RhB than pure BLOC1and also shows high stability.This work provides a new strategy for the design of a highly efficient hybrid photo- catalyst driven by visible light.
基金supported by the National Natural Science Foundation of China(91023030,51072044,51102071 and 51128201)the International Scientific and Technological Cooperation Project of Anhui Province(10080703017)
文摘A facile and environment friendly approach to synthesis of unique hierarchical BiOCl flowery microspheres(FMs)using a biodegradable surfactant polyvinyl alcohol(PVA)was reported herein for the first time.Compared to the BiOCl nanosheets synthesized in the absence of PVA,hierarchical BiOCl FMs consist of large amounts of interwoven polycrystalline nanosheets that assemble into a porous flowery structure.The formation mechanism of the hierarchical BiOCl FMs was also proposed,whereby PVA was believed to play a key role in the crystal growth and the formation of the final microstructures.Compared with TiO2-P25 and BiOCl nanosheets,hierarchical BiOCl FMs displayed remarkably enhanced photocatalytic activity,and20 mg of BiOCl FMs could completely degrade 50 mL of methyl orange solution(20 mg/L)within 30 min under UVlight irradiation.According to the comprehensive analysis,it can be concluded that the larger specific surface area,porosity,suitable band gap,and the enhanced light absorption capacity may contribute to the remarkably enhanced photocatalytic activity.This facile and green approach to fabricating hierarchical BiOCl FMs would give vital clues to develop new route for synthesizing other hierarchical structured materials.
