The influence of n-type and p-type dopants on the interfacial charge transfer and the band structure of Bi2MoO6 to enhance solar H2 production

Abstract NiO and CdS loaded Bi 2 MoO 6 nanocompositephotocatalysts were synthesized by using hydrothermal method followed by an impregnation method. The performances of the synthesized materials were evaluated for H 2 production under direct solar light irradiation.Among the synthesized catalysts, 1 wt% NiO/CdS-Bi 2 MoO 6 showed the highest H 2 production.The characterization results revealed that the porous and orthorhombic structure of Bi 2 MoO 6 . The heterojunctions at the interfaces of NiO(p-type) and CdS(n-type) nanocrystals with Bi 2 MoO 6 (n-type) nanoparticles were revealed by HRTEM images.The n-n and p-n type junctions at the interfaces of the nanocrystals played very important roles to improve the interfacial charge transfer (IFCT) and to extend the life time of the photogenerated charge carriers, thesephenomena were confirmed by the photoelectrochemical and photoluminescence studies. The donor (n-type) and acceptor (p-type) dopantsonBi 2 MoO 6 significantly reduced the band gap and shifted the light absorption edge position to longer wavelength than the single doped materials, which was confirmed by DR UV-Vis spectroscopy. Hence,the favourable characteristic changes on Bi 2 MoO 6 created by the presence of both NiO and CdSsynergistically enhanced the rate of H 2 production 3 times higher than that of the pristineBi 2 MoO 6 .This work provides aprofundity on the development of solar light responsive Bi 2 MoO 6 based photocatalysts for H 2 production.