摘要
Photocatalytic hydrogen evolution from water splitting is an appealing method for producing clean chemical fuels.Cu_(2)O,with a suitable bandgap,holds promise as a semiconductor for this process.However,the strong photo-corrosion and rapid charge recombination of Cu_(2)O strongly limit its application in the photocatalytic fields.Herein,an S-scheme heterojunction photocatalyst composed of TiO_(2)and Cu_(2)O was rationally designed to effectively avoid the photo-corrosion of Cu_(2)O.The introduction of an interfacial nitrogen-doped carbon(NC)layer switches the heterojunction interfacial charge transfer pathway from the p-n to S-scheme heterojunction,which avoids excessive accumulation of photogenerated holes on the surface of Cu_(2)O.Meanwhile,the hybrid structure shows a broad spectral response(300-800 nm)and efficient charge separation and transfer efficiency.Interestingly,the highest photocatalytic hydrogen evolution rate of TiO_(2)-NC-3%Cu_(2)O-3%Ni is 13521.9μmol g^(-1)h^(-1),which is approximately 664.1 times higher than that of pure Cu_(2)O.In-situ X-ray photoelectron spectroscopy and Kelvin probe confirm the charge transfer mechanism of S-scheme heterojunction.The formation of S-scheme heterojunctions effectively accelerates the separation of photogenerated electron-hole pairs and enhances redox capacity,thereby improving the photocatalytic performance and stability of Cu_(2)O.This study provides valuable insights into the rational design of highly efficient Cu_(2)O-based heterojunction photocatalysts for hydrogen production.
基金
X.Li thanks the National Natural Science Foundation of China(Nos.21975084 and 51672089)
the Natural Science Foundation of Guangdong Province(No.2021A1515010075)for their support.
X.Peng thanks the State Key Laboratory of Pollution Control and Resource Reuse Foundation(No.PCRRF21028)for the support.
