Synergistic effect of interstitial phosphorus doping and MoS2 modification over Zn0.3Cd0.7S for efficient photocatalytic H2 production
Qian Liu, Junhua You, Ya Xiong, Wendi Liu, Mingfang Song, Jiali Ren, Qingzhong Xue, Jian Tian, Hangzhou Zhang, Xiaoxue Wang
Abstract
Zn x Cd 1-x S photocatalysts have been widely investigated due to their diverse morphologies, suitable band gaps/band edge positions, and high electronic mobility. However, the sluggish charge separation and severe charge recombination impede the application of Zn x Cd 1-x S for hydrogen evolution reaction (HER). Herein, doping of phosphorus (P) atoms into Zn 0.3 Cd 0.7 S has been implemented to elevate S vacancies concentration as well as tune its Fermi level to be located near the impurity level of S vacancies, prolonging the lifetime of photogenerated electrons. Moreover, P doping induces a hybridized state in the bandgap, leading to an imbalanced charge distribution and a localized built-in electric field for effective separation of photogenerated charge carriers. Further construction of intimate heterojunctions between P-Zn 0.3 Cd 0.7 S and MoS 2 accelerates surface redox reaction. Benefiting from the above merits, 1 % MoS 2 /P-Zn 0.3 Cd 0.7 S exhibits a high hydrogen production rate of 30.65 mmol·g −1 ·h −1 with AQE of 22.22 % under monochromatic light at 370 nm, exceeding most Zn x Cd 1-x S based photocatalysts reported so far. This work opens avenues to fabricate examplary photocatalysts for solar energy conversion and beyond.