ZnSe and CdS Co‐Sensitized TiO2 Nanorod Arrays as Photoanodes for Bias‐Free Solar Hydrogen Evolution. Issue 11 (22nd November 2022)

• Record Type: Journal Article
• Authors: Gunasekaran, Ashokan; Sadhasivam, Subramani; Anbarasan, Nallathambi; Jeganathan, Kulandaivel
• Is Part Of: ChemPlusChem. Volume 87:Issue 11(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-11-22
• Subjects: heterostructures -- nanostructures -- photoelectrodes -- semiconductors -- solar water splitting; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/cplu.202200304
• Languages: English
• ISSNs: 2192-6506

Abstract

Abstract: The efficient charge separation and surface state reactions are significant in enhancing the efficiency of photoelectrochemical hydrogen evolution. Herein, we report a ternary heterostructure consisting of CdS/ZnSe sensitized TiO2 nanorod as a photoanode. The heterojunction photoanode considerably widens the photon absorption spectral range and thereby enhances the photocurrent density up to 2 mA/cm 2 at 1.23 V versus RHE which is 10 times higher than pristine TiO2 photoanode. The photoelectrochemical results demonstrate a high photocurrent density of 2 mA/cm 2 with a photon‐to‐current conversion efficiency of 1.5 % at a very low applied bias (0.2 V vs RHE). The improved PEC performances of the multidimensional hybrid photoanode could be ascribed to the efficient visible‐light absorption of ZnSe and CdS nanocrystals decorated on the surface of 1D TiO2 . The rapid electron‐transfer properties owing to higher carrier density, low carrier transport resistance, and an extended lifetime of photoexcited carriers in the multidimensional ZnSe/CdS/TiO2 heterostructure with suppressed surface charge recombination are responsible for enhanced hydrogen evolution activities. Abstract : The triadic heterostructures of a CdS/ZnSe/TiO2 photo‐electrode have been constructed for photo‐electrochemical water splitting applications. The CdS and ZnSe nanocrystal decorated on TiO2 NRs facilitates a substantial enhancement in the photo‐electro catalytic performance. The photo‐electrode operates in the self‐biased condition under visible light illumination and is highly stable in the electrolyte. The results show that the triadic heterostructures could be used to improve PEC water splitting performance.