The development of low-cost, earth-abundant and highly-efficient cocatalysts is still important to promote the photocatalytic H2 evolution reaction over semiconductors. Herein, a series of Ni nanoclusters（NCs） modif...The development of low-cost, earth-abundant and highly-efficient cocatalysts is still important to promote the photocatalytic H2 evolution reaction over semiconductors. Herein, a series of Ni nanoclusters（NCs） modified brookite TiO2 quasi nanocubes（BTN）（marked as Ni/BTN） are fabricated via a chemical reduction process. It is found that the loading content and oxidation state of Ni NCs can significantly influence the optical absorption, photocatalytic activity, and stability of Ni/BTN composites. Among the resultant Ni NCs-loaded products, 0.1%Ni/BTN composite delivers the best H2 evolution activity（156 μmol/h）,which is 4.3 times higher than that of the BTN alone（36 μmol/h）. Furthermore, the Ni NCs with ultrafine size（2 nm） and high dispersity enable shorter charge transfer distance by quickly capturing the photoexcited electrons of BTN, and thus result in the improved activity even though the oxidization of some Ni NCs on BTN is harmful to the activity for H2 evolution due to the much lower electron capturing capability of NiO than metallic Ni.This study not only clarifies that brookite TiO2 would be a promising high-efficient photocatalyst for H2 evolution, but also reveals vital clues for further improving its photocatalytic performance using low-cost Ni-based cocatalyst.展开更多
基金the National Natu-ral Science Foundation of China(No.21573166 and No.21271146)the Funds for Creative Research Groups of Hubei Province(No.2014CFA007)+2 种基金the Natural Sci-ence Foundation of Jiangsu Province(No.BK20151247)the Science Foundation of Jiangxi Provincial Of-ce of Education(No.GJJ180854)and the Post-Doctoral Start-up Project of Yichun University(NACPB20180201),China.
文摘The development of low-cost, earth-abundant and highly-efficient cocatalysts is still important to promote the photocatalytic H2 evolution reaction over semiconductors. Herein, a series of Ni nanoclusters（NCs） modified brookite TiO2 quasi nanocubes（BTN）（marked as Ni/BTN） are fabricated via a chemical reduction process. It is found that the loading content and oxidation state of Ni NCs can significantly influence the optical absorption, photocatalytic activity, and stability of Ni/BTN composites. Among the resultant Ni NCs-loaded products, 0.1%Ni/BTN composite delivers the best H2 evolution activity（156 μmol/h）,which is 4.3 times higher than that of the BTN alone（36 μmol/h）. Furthermore, the Ni NCs with ultrafine size（2 nm） and high dispersity enable shorter charge transfer distance by quickly capturing the photoexcited electrons of BTN, and thus result in the improved activity even though the oxidization of some Ni NCs on BTN is harmful to the activity for H2 evolution due to the much lower electron capturing capability of NiO than metallic Ni.This study not only clarifies that brookite TiO2 would be a promising high-efficient photocatalyst for H2 evolution, but also reveals vital clues for further improving its photocatalytic performance using low-cost Ni-based cocatalyst.
