Designing innovative Zn3(VO)4/BiVO4 heterojunction for enhanced photodegradation under solar irradiation

The design of hybrid photocatalysts has gained significant attention as an innovative strategy to enhance the separation of photogenerated charge carriers, thereby boosting photocatalytic efficiency. Herein, nanocomposites comprising of zinc vanadate and bismuth vanadate in varying proportions are synthesized via co-precipitation method to evaluate their potential in degrading organic dyes. Among the synthesized composites, ZBVO-60 demonstrates optimal performance, achieving 96.92 % degradation of methylene blue (MB) with a rate constant of 0.0191 min⁻¹ and 95.63 % degradation of methyl green (MG) with k = 0.0148 min⁻¹ upon solar irradiation. The superior photocatalytic efficiency is attributed to its enhanced light absorption, supported by narrow bandgap of 2.23 eV, decreased charge transfer resistance and efficient transport of photogenerated carriers at the interface. Moreover, the activation energy on the account of Arrhenius equation is noted to be 59.55 J/mol for MB and 97.83 J/mol for MG. ⋅OH is identified as the primary contributors to degradation in reactive-species trapping experiments, while Z-scheme mechanism is proposed to elucidate the charge transfer and separation dynamics. The stability tests confirm robustness of ZBVO-60, with negligible variations in photocatalytic efficiency across 5 cycles. These findings underscore the capability of hybrid as promising and sustainable photocatalysts for wastewater treatment and environmental remediation applications.