Enhanced Solar‐Photo(Electro)catalysis of Microwave‐Hydrothermal Synthesized BiVO4, ms‐BiVO4/Reduced Graphene Oxide/Ag3PO4 Nanohybrid: Crystalline Phase‐Dependent Interfacial Charge Carrier Dynamics

Abstract

Bismuth vanadate with reduced graphene oxide (BiVO4/RGO) is prepared via ultrafast, energy‐efficient microwave‐assisted hydrothermal technique. Subsequently, Ag3PO4 nanoparticles are decorated on BiVO4/RGO by impregnated solution process. Photoelectrochemical (PEC) performance is carried out using as‐synthesized ternary heterostructure ms‐BiVO4/RGO/Ag3PO4 nanohybrid photoanode film and Pt‐wire as cathode in 0.5 m Na2SO4 electrolyte solution under AM 1.5 G (100 mW cm−2) irradiation. An enhanced photocurrent density of ≈3.6 mA cm−2 at +1.23 VRHE is observed for water oxidation, which is ≈2.3 times higher than pristine ms‐BiVO4 (1.58 mA cm−2). Furthermore, 10.1% of incident light‐to‐photocurrent conversion at λ = 450 nm and improved solar‐to‐hydrogen conversion efficiency of 4.5% with consistent photostability up‐to 24 h is achieved. While Rhodamine‐B dye degradation is investigated using BiVO4/RGO/Ag3PO4 photocatalyst, offers highest visible‐light‐driven photocatalytic (PC) degradation with average rate constant of kavg = 1.70 × 10−1 min−1 in 20 min, ≈4.3 times higher than pristine ms‐BiVO4. Such enhancement in PEC and PC performances is due to improved light absorbance coefficient with extended hole diffusion length (LPEC/PC = 209/147 nm) that enables efficient interfacial charge separation, transportation, and reduced photoinduced recombination. Herein, a strategy of designing an efficient nanohybrid photo(electro)catalyst to generate H2 fuel from water oxidation process and for environmental remediation is developed.