物理化学学报2021，Vol.37Issue(6)：107-118,12.DOI:10.3866/PKU.WHXB202008030
构建NiS2/MoSe2 S型异质结高效光催化产氢
High Efficiency Electron Transfer Realized over NiS2/MoSe2 S-Scheme Heterojunction in Photocatalytic Hydrogen Evolution
摘要
Abstract
S-scheme heterojunction is a major breakthrough in the field of photocatalysis.In this study,NiS2 and MoSe2 were prepared by a typical solvothermal method,and compounded by an in situ growth method to construct an S-scheme heterojunction.The obtained composite showed excellent performance in photocatalytic hydrogen evolution;the hydrogen production rate was approximately 7 mmol.h-1.g-1,which was 2.05 times and 2.44 times those of pure NiS2 and MoSe2,respectively.Through a series of characterizations,it was found that NiS2 and MoSe2 coupling can enhance the light absorption intensity,which is vital for the light reaction system.The efficiency of electron-hole pair separation is also among the important factors restricting photocatalytic reactions.Compared with pure NiS2 and MoSe2,NiS2/MoSe2 exhibited a higher photocurrent density,lower cathode current,and lower electrochemical impedance,which proves that the NiS2/MoSe2 complex can effectively promote photogenerated electron transfer.Simultaneously,the lower emission intensity of fluorescence indicated effective inhibition of electron-hole recombination in the NiS2/MoSe2 complex,which is favorable for the photocatalytic hydrogen evolution reaction.Further,scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that MoSe2 is an amorphous sample surrounded by the NiS2 nanomicrosphere,which greatly increased the contact area between the two,thus increasing the active site of the reaction.Secondly,as a photosensitizer,Eosin Y (EY) effectively enhanced the absorption of light by the catalyst in the photoreaction system.Meanwhile,during sensitization,electrons were provided to the catalyst,which effectively improved the photocatalytic reaction efficiency.The establishment of S-scheme heterojunctions contributed to improving the redox capacity of the reaction system and was the most important link in the photocatalytic hydrogen reduction of aquatic products.It was also the main reason for the improvement of the hydrogen evolution effect in this study.The locations of the conduction band and valence band of NiS2 and MoSe2 were determined by Mott-Schottky plots and photon energy curves,and further proved the establishment of the S-scheme heterojunction.This work provides a new reference for studying the S-scheme heterojunction to effectively improve the photocatalytic hydrogen production efficiency.关键词
NiS2/MoSe2/S型异质结/光催化产氢Key words
NiS2/MoSe2/S-scheme heterojunction/Photocatalytic hydrogen evolution分类
化学化工引用本文复制引用
刘阳,郝旭强,胡海强,靳治良..构建NiS2/MoSe2 S型异质结高效光催化产氢[J].物理化学学报,2021,37(6):107-118,12.基金项目
This work was financially supported by the Natural Science Foundation of the Ningxia Hui Autonomous Region,China (2020AAC02026,2020AAC03204),the Open Project of State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering,Ningxia University,China (2019-KF-36),the Ningxia Low-Grade Resource High Value Utilization and Environmental Chemical Integration Technology Innovation Team Project,North Minzu University,China.宁夏自然科学基金重点项目(2020AAC02026),宁夏自然科学基金一般项目(2020AAC03204),省部共建煤炭高效利用与绿色化工国家重点实验室开放课题重点项目(2019-KF-36),宁夏低品位资源高值化利用及环境化工一体化技术创新团队资助 （2020AAC02026,2020AAC03204）
