【摘 要】
:
Hydrogen energy is a powerful and efficient energy resource,which can be produced by photocatalytic water split-ting.Among the photocatalysis,multinary copper-based chalcogenide semiconductor nanocrystals exhibit great potential due to their tunable cryst
【机 构】
:
Key Laboratory of Luminescence and Optical Information,Ministry of Education,School of Science,Beiji
论文部分内容阅读
Hydrogen energy is a powerful and efficient energy resource,which can be produced by photocatalytic water split-ting.Among the photocatalysis,multinary copper-based chalcogenide semiconductor nanocrystals exhibit great potential due to their tunable crystal structures,adjustable optical band gap,eco-friendly,and abundant resources.In this paper,Cu-Zn-Sn-S(CZTS)nanocrystals with different Cu content have been synthesized by using the one-pot method.By regulating the surface ligands,the reaction temperature,and the Cu content,kesterite and hexagonal wurtzite CZTS nanocrystals were ob-tained.The critical factors for the controllable transition between two phases were discussed.Subsequently,a series of quatern-ary CZTS nanocrystals with different Cu content were used for photocatalytic hydrogen evolution.And their band gap,energy level structure,and charge transfer ability were compared comprehensively.As a result,the pure hexagonal wurtzite CZTS nano-crystals have exhibited an improved photocatalytic hydrogen evolution activity.
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