Size- and composition-dependent photocatalytic hydrogen production over colloidal Cd1-xZnxSe nanocrystals. (26th July 2018)

• Record Type: Journal Article
• Authors: Chen, Yubin; Guo, Xu; Xie, Cheng; Qin, Zhixiao; Feng, Xiaoyang
• Is Part Of: International journal of hydrogen energy. Volume 43:Number 30(2018)
• Page Start: 13911
• Page End: 13920
• Publication Date: 2018-07-26
• Subjects: Cd1-xZnxSe -- Nanocrystals -- Photocatalyst -- Solar energy -- Hydrogen production; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2018.01.178
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Colloidal nanocrystals (NCs) have emerged as a new kind of photocatalysts for solar hydrogen production due to the tunable optical and photoelectrical properties. Herein, size- and composition-tunable alloyed Cd1-x Znx Se NCs were successfully prepared via a one-step hot injection method for photocatalytic hydrogen production under visible light irradiation. By prolonging the reaction time, CdSe NCs with the varied particle sizes were firstly fabricated. It is found that the driving force derived from the difference between conduction band position of CdSe NCs and water reduction potential played a key role in determining the photocatalytic performance. The larger driving force from smaller particle size would give rise to a faster electron transfer and better photocatalytic activity. Furthermore, a series of alloyed Cd1-x Znx Se NCs with different compositions were prepared. With the increased zinc amount, the photocatalytic activity of Cd1-x Znx Se NCs was initially increased and then decreased. Cd1-x Znx Se with the moderate Zn content exhibited the best photocatalytic hydrogen production. It is inferred that the photocatalytic performance of Cd1-x Znx Se NCs has a close relationship with the driving force and crystal structure. The present study can provide a guidance to develop efficient nanocrystal photocatalysts by simply controlling the particle size and composition. Highlights: Colloidal Cd1-x Znx Se nanocrystals (NCs) were prepared by a one-step hot injection route. The photocatalytic performance of NCs could be controlled by tuning the size and composition. The larger driving force from smaller particle size of CdSe NCs led to better photocatalytic activity. Cd1-x Znx Se with the moderate Zn content exhibited the best photocatalytic hydrogen production.