Optimized the Carrier Transport Path and Separation Efficiency of 2D/2D Heterojunction in Photoelectrochemical Water Splitting. Issue 8 (16th February 2021)

• Record Type: Journal Article
• Authors: Qian, Hongxia; Liu, Zhifeng; Zhang, Bo; Li, Junwei; Ya, Jing
• Is Part Of: ChemCatChem. Volume 13:Issue 8(2021)
• Page Start: 1940
• Page End: 1950
• Publication Date: 2021-02-16
• Subjects: 2D/2D heterojunction -- co-catalyst -- photoelectrode -- charge separation -- photoelectrochemical water splitting; Catalysis -- Periodicals; 541.39505
• DOI: 10.1002/cctc.202001765
• Languages: English
• ISSNs: 1867-3880

Abstract

Abstract: It is a promising strategy that the photoelectrode with high charge transfer rate and separation efficiency is designed in the photoelectrochemical (PEC) water splitting. Herein, the nanoflakes/nanoflakes (2D/2D) MoS2 /ZnIn2 S4 heterojunction is synthesized by two‐step hydrothermal methods. The carrier transport path in heterojunction is optimized through the Schottky contact calculated by density functional theory (DFT) and large specific surface area between 2D nanoflakes MoS2 and ZnIn2 S4 . Besides, the bimetallic oxyhydroxide NiFeOOH can be used as co‐catalyst to improve the separation of carriers. The results exhibit that MoS2 /ZnIn2 S4 /NiFeOOH photoelectrode with dramatically enhanced photocurrent density of 0.74 mA/cm 2 at 1.23 V versus the reversible hydrogen electrode (VRHE ), which is 2.6 and 5.7 times higher than the bare MoS2 and ZnIn2 S4, respectively. And it has the largest charge separation efficiency (ηbulk ) (22.8 %) and charge transfer efficiency (ηsurface ) (64.6 %) in the as‐prepared samples. This work provides a strategy for design of the photoelectrode with excellent charge transfer efficiency and separation efficiency in PEC water splitting. Abstract : 2D/2D heterojunction : MoS2 /ZnIn2 S4 /NiFeOOH photoanode was synthesized by two‐step hydrothermal method and ultrafast deposition at room temperature. The Schottky contact at the 2D/2D MoS2 /ZnIn2 S4 interface can optimize the carrier transport path in the heterojunction. As a co‐catalyst, NiFeOOH improve separation and transfer efficiency of the charge at the interface significantly. The cooperation of 2D/2D heterojunction and co‐catalyst optimizes carrier transmission and separation to achieve a photocurrent density of 0.74 mA/cm 2 .