Metal organic frameworks constructed heterojunction with α-NiS-β-NiS/CdS: The effect of organic-ligand in UiO-66 for charge transfer of photocatalytic hydrogen evolution

摘要

Developing favorable charge transfer mode for photocatalytic hydrogen evolution in a photocatalyst is a promising way to enhance photocatalytic activity. In this study, MOF, decorated with different functional groups, was initially used as charge transfer mode convertor coupled with CdS/alpha-NiS-beta-NiS. The NH2-UiO-66/CdS/alpha-NiS-beta-NiS lead to twice and triple higher H-2 evolution compared to (OH)(2)-UiO-66/CdS/alpha-NiS-beta-NiS and UiO-66/CdS/alpha-NiS-beta-NiS respectively under simulated sunlight. The NH2-UiO-66 provides suitable energy band structure to formed Z-scheme with CdS/alpha-NiS-beta-NiS, which plays a synergistic role in the photocatalytic process. The loading of alpha-NiS-beta-NiS significantly improves the visible light absorption ability and provides abundant active sites. As a result, the alpha-NiS-beta-NiS/CdS/NH2-UiO-66 show considerable photocatalytic hydrogen production rate of 17.88 mmol h(-1) g(-1), which is 7.9 times and 2.5 times as high as-those of pure CdS and 7-alpha-NiS-beta-NiS/CdS, and it also shows a prominent apparent quantum efficiency (AQE) of 14.7% at 420 nm. This work provides a new insight design a metal organic frameworks based heterojunction with highly-efficient photo-induced charge separation and excellent visible-light absorption ability. (c) 2020 Elsevier Ltd. All rights reserved.