Interfacial modification and band modulation for dramatically boosted photocatalytic hydrogen evolution

Abstract

Interfacial modification and band modulation to narrow the band gap and improve light-harvesting ability of TiO2 are promising strategies to dramatically promote photocatalytic activity. Herein, efficient Co(OH)2-TiO2 nanocomposites were reasonably designed and constructed by a facile room temperature solid-state synthetic strategy for interfacial modification and matched band gap to achieve the conversion of solar energy to hydrogen. Modifying transition metal hydroxide Co(OH)2 on commercial TiO2 can effectively narrow the band gap and accelerate the separation and migration of photo-induced carriers, which will extend light absorption range and facilitate more electrons transferring to the surface of photocatalyst, therefore the reducibility of photocatalysts is enhanced. The modified photocatalyst exhibits high photocatalytic hydrogen evolution activity and stability. Specifically, the obtained TCO-0.6 shows excellent photocatalytic hydrogen evolution rate of 21343.01 μmol g−1 and is 23 times superior to commercial TiO2. This work not only emphasizes a facile strategy for interfacial modification and band modulation under mild condition, but also provides a novel avenue for improving the performance of photocatalytic hydrogen evolution.