Bi2S3 entrenched BiVO4/Wo3 multidimensional triadic photoanode for enhanced photoelectrochemical hydrogen evolution applications

The catalytic reactivity and photoactivity of WO3 and BiVO4 oxide semiconductors have general obstacles as electrodes in emergent photo-electrochemical (PEC) hydrogen evolution applications. The present work comprises the integration of photocatalyst with wide visible photon absorption material which is vital for hydrogen evolution in photo-electrocatalytic water splitting. Herein, the 1D WO3 NWs have been integrated with stable water oxidation photocatalysts of BiVO4 and Bi2S3 as a photoanode (Bi2S3/BiVO4/WO3) for photoelectrochemical hydrogen evolution reactions. The morphological variations in the Bi2S3/BiVO4/WO3 heterostructure manifest catalytic activity and rapid charge transfer characteristics owing to band alignment and a wide range of visible photon absorption. The optimized Bi2S3/BiVO4/WO3 multidimensional photoanode accomplishes a superior photocurrent density of 1.52 mA/cm(2), a seven-fold higher than pristine WO3 photoanode counterpart (0.2 mA/cm(2)) at 1 V vs. RHE. A prodigious lowest onset potential of -0.01 V vs. RHE) has been achieved which enables very high solar to hydrogen conversion. The photoelectrode with entangled morphology such as nanosheets, nanocrystals and nanorods expanded their surface to volume ratio having enhanced catalytic performance. The hybrid photoanodes have demonstrated the lowest charge transfer resistance of 360 Ohm/cm(2) with a 7-fold rise in hydrogen evolution performance. The resultant triadic Bi2S3/BiVO4/WO3 heterostructure appeared to be an emerging stable photo-electro catalyst for hydrogen evolution applications. (C) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

In this study, 1D WO3 nanowires were integrated with stable water oxidation photocatalysts of BiVO4 and Bi2S3 to form a heterostructure of Bi2S3/BiVO4/WO3. The resultant structure exhibited superior catalytic activity and rapid charge transfer characteristics, showing potential importance in hydrogen evolution applications.