Enhancing hydrogen generation via fabricating peroxide decomposition layer over NiSe/MnO2-CdS catalyst

• Published in: Journal of catalysis 2018-11, Vol.367, p.269-282
• Main Authors: Zhen, Wenlong, Ning, Xiaofeng, Wang, Meng, Wu, Yuqi, Lu, Gongxuan
• Format: Article
• Language: English
• Subjects: Fabricating peroxide decomposing active MnO2 thin-layer; Inhibition of CdS photocorrosion; Over-all water splitting; Remove nascent formed oxygen by artificial gill; Replacing noble metal co-catalyst with NiSe QDs
• ISSN: 0021-9517; 1090-2694
• DOI: 10.1016/j.jcat.2018.09.019

[Display omitted] •MnO2 thin-layer can decompose peroxide specie and enhance water splitting activity.•Non-noble metal co-catalyst NiSe is active for water splitting.•Removing nascent formed O2 from water by artificial gill can prevent the oxygen leading CdS photocorrosion.•Enhanced charges transfer over NiSe QDs and MnO2 thin-layer in CdS.•The excellent stability of NiSe/MnO2-CdS for HER is achieved for water splitting. CdS is a promising visible-light responsive photocatalyst. However, the serious photocorrosion limits its application in photocatalysis. Here we report a novel strategy to overcome the disadvantage of CdS photocorrosion by fabricating peroxide decomposing active MnO2 thin-layer over CdS nanowires (NWs) and assembling oxygen separation artificial gill to remove nascent formed oxygen in the dispersion. In the meantime, the using non-noble metal NiSe quantum dots (QDs) co-catalyst, NiSe/MnO2-CdS photocatalysts shows excellent photocatalytic over-all water splitting activity and remarkable stability under visible light irradiation without addition of any sacrifice reagent, 455.0 µmol h−1 g−1 of hydrogen evolution reaction (HER) rate and 5.20% of apparent quantum efficiency (AQEs) at 430 nm. Removing nascent formed O2 from water by artificial gill can prevent the oxygen leading CdS photocorrosion. Photoluminescence spectra and photoelectrochemical measurements indicate that loading NiSe QDs and coating MnO2 thin-layer can also improve transfer of the photogenerated charges in CdS. MnO2 thin-layer can decompose formed hydrogen peroxide and enhance water splitting. Our results could potentially provide a new method for designing and fabricating more stable and efficient CdS-based nanocomposite photocatalysts toward versatile solar energy conversion.