Tailoring multi-layered BiVO4/WO3 photoanodes for an efficient photoelectrochemical gas-phase solar water splitting

Photoelectrochemical gas-phase solar water splitting represents a promising avenue for sustainable hydrogen production, fulfilling the energy demands of the future. In this work, we present the fabrication and optimization of the functional performance of visible-light active BiVO4/WO3 photoanodes w...

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Bibliographic Details
Authors: Merino García, Iván, Crespo Álvarez, Sara|||0009-0004-8089-9518, Perfecto-Irigaray, Maite, Beobide Pacheco, Garikoitz, Irabien Gulías, Ángel|||0000-0002-2411-4163, Albo Sánchez, Jonathan|||0000-0001-6781-5704
Format: article
Publication Date:2024
Country:España
Institution:Universidad de Cantabria (UC)
Repository:UCrea Repositorio Abierto de la Universidad de Cantabria
Language:English
OAI Identifier:oai:repositorio.unican.es:10902/32918
Online Access:https://hdl.handle.net/10902/32918
Access Level:Open access
Keyword:Photoelectrocatalysis
BiVO4/WO3 photoanodes
Solar hydrogen
Gas phase
Description
Summary:Photoelectrochemical gas-phase solar water splitting represents a promising avenue for sustainable hydrogen production, fulfilling the energy demands of the future. In this work, we present the fabrication and optimization of the functional performance of visible-light active BiVO4/WO3 photoanodes with a tailored multi-layered structure. The photoanodes are manufactured in a reproducible way by an automated spray pyrolysis technique, including BiVO4 (top layer) and WO3 (bottom layer) in a multi-layered structure with different ratios (80:20; 50:50; 20:80). The photoactive surfaces are fully characterized and then evaluated in a divided filter-press reactor operated in continuous mode under visible light irradiation (100 mW cm−2), where a platinized titanium plate is used as dark cathode. The results demonstrate the pivotal role of mass ratio in optimizing charge transfer kinetics and recombination rates in the photoanode. We demonstrate the synergistic effects between BiVO4 and WO3, elucidating their contributions to enhance light absorption, and reduce electron-hole recombination, determining an optimal ratio of 80:20 for both hydrogen production (155.7 μmol m−2 s−1) and on-off current density gap (0.66 mA cm−2). The developed multi-layered BiVO4/WO3 surfaces thus offer a compelling pathway for advancing gas-phase photoelectrochemical water splitting technology, underscoring the significance of electrode design and paving the way for sustainable solar hydrogen production.