Enhanced photocatalytic hydrogen evolution along with byproducts suppressing over Z-scheme CdxZn1-xS/Au/g-C3N4 photocatalysts under visible light

• 来源期刊: 科学通报（英文版）
• 年，卷（期）: 2017,（9）
• 页码范围: 602-609
• 页数: 8页
• 语种: 英文

摘要

Inspired by natural photosynthesis,a new series of Z-scheme CdxZn1-xS/Au/g-C3N4 pnotocatawsts were synthesized via depositing Au particles on g-C3N4,followed by anchoring CdxZn1-xS solid solution on the pre-formed Au/g-C3N4 for photocatalytic hydrogen evolution.Their structure,morphology and optical property were investigated in detail.Photocatalytic activities of the developed photocatalysts for water splitting were evaluated under visible-light irradiation (λ ＞ 420 nm) using glucose as electron donor.The highest hydrogen evolution rate of 123 μmol g-1 h-1 is achieved by Cdo.sZn0.2S/Au/g-C3N4,which is 52.2 and 8.63 times higher than that of Au/g-C3N4 and CdS/Au/g-C3N4,respectively.The results of photoluminescence spectra,photoelectrochemical and time-resolved photoluminescence spectra indicate that the improved photocatalytic activities for CdxZn1-xS/Au/g-C3N4 are due to the efficient separation of photogenerated carriers.In addition,it is noteworthy that the undesired byproducts CO and CO2 are greatly reduced by introducing CdxZn1-xS over Au/g-C3N4 surface.In the photocatalytic process,gluconic acid originated from the reaction of photogenerated hydroxyl radical with glucose plays a vital role on suppressing the formation of the gas byproducts.The present work will provide a new strategy to design Z-scheme photocatalysts with enhanced efficiency for water splitting along with suppressing the byproducts.