Laser-assisted FTO/WO3/BiVO4 photoanode fabrication for enhanced photoelectrocatalytic performance and durability for organic dye degradation

Abstract

A significant challenge in the photoelectrocatalytic method for water oxidation and organic decomposition processes is the fabrication of scalable, durable, and efficient photoanodes. Several limitations, such as insufficient adhesion, uneven semiconductor coatings, and low durability, often lead to the unsatisfactory performance of the conventional FTO/WO₃/BiVO₄ photoanode. This study improves the surface properties of fluorine-doped tin oxide (FTO) substrates using a laser treatment process prior to the automated dip-coating of WO₃ and BiVO₄ semiconductor layers. The FTO substrate surface is textured and modified using laser induction as part of the fabrication process. Thereafter, WO₃ and BiVO₄ semiconductor layers are deposited in sequence. The laser treatment can promote surface homogeneity, semiconductor adhesion, and the active surface area of the fabricated FTO/WO₃/BiVO₄. The morphology, elemental composition, and electrochemical properties are analyzed using SEM, EDS, and EIS techniques. In that context, the laser-treated FTO/WO₃/BiVO₄ photoanode development significantly outperformed those without treatment. The FTO/WO₃/BiVO₄ photoanode that was treated with a laser had a lower energy band gap of 1.8 eV, a higher capacitance of 4.91 × 10^-6 F, and a higher photocurrent density of 5.5 mA/cm² compared to an electrode that was not treated with a laser at a bias potential of 1.0 V. The durability assessments demonstrated that the organic dye removal efficacy persisted after 1,000 hours. This study demonstrates that laser-treated FTO/WO₃/BiVO₄ photoanodes can overcome conventional fabrication method limitations. This successfully provides a scalable and effective alternative for various applications, including wastewater treatment and renewable energy. It is recommended that subsequent studies should focus on the evaluation of the applicability of this laser-assisted method to various kinds of environmental applications and photoelectrodes.