Recent Advances in Bismuth Vanadate Quantum Dot Nanophotocatalysts: From Synthesis to Applications in Wastewater Treatment and Clean Energy Production

Bismuth vanadate (BiVO) quantum dots (QDs) have emerged as a strategically engineered class of visible-light-responsive nanophotocatalysts, effectively circumventing the intrinsic thermodynamic and kinetic limitations of bulk BiVO۴. By leveraging quantum confinement effects and advanced heterojunction architectures, BiVO۴ QDs exhibit a widened bandgap (~۲.۶-۲.۷ eV), an upward-shifted conduction band (~۰.۲۰-۰.۲۵ eV), and drastically shortened charge diffusion pathways. This review critically synthesizes recent advances across the synthesis, charge engineering, and application domains of BiVO۴ QD-based systems. We systematically evaluate hydrothermal/solvothermal, successive ionic layer adsorption and reaction (SILAR), flame spray pyrolysis (FSP), ultrasonic-assisted bio-templating, and electrostatic self-assembly routes, highlighting their respective impacts on size control, interfacial intimacy, crystallinity, and scalability. The evolution of charge transfer mechanisms from Type-II to Z-scheme and S-scheme configurations is analyzed, with particular emphasis on how built-in electric fields, work-function gradients, and piezo-potential assistance drive separation efficiencies up to ۹۹.۶%. Applications are critically assessed across wastewater remediation (dye degradation, antibiotic mineralization, continuous-flow reactors) and clean energy production (CO۲-to-fuel conversion, H۲O۲ photosynthesis, bias-free H۲ evolution). Despite notable progress, persistent challenges remain in mechanistic validation, long-term operational stability under complex matrices, standardized performance benchmarking, and scalable manufacturing. This review delineates these research gaps and proposes targeted trajectories-including operando spectroscopic validation, machine learning-guided synthesis optimization, pilot-scale reactor engineering, and life-cycle assessment-to accelerate the translational deployment of BiVO۴ QD photocatalysts in sustainable environmental and energy technologies.

Keywords:

Bismuth vanadate quantum dots , Heterojunction engineering , Charge carrier dynamics , Photocatalytic wastewater treatment