Enhanced adsorption-photocatalysis of organic pollutants using an Ag-CuBi₂O₄/WO₃/SL-GO nanocomposite

Water pollution poses a serious threat to ecosystems and human health, requiring effective and sustainable treatment strategies. While conventional methods often fall short, there remains a significant research gap in developing highly efficient hybrid systems that combine enhanced adsorption with potent visible light photocatalysis. Herein, we report the novel synthesis of a unique 1D/0D/2D heterostructure photocatalyst, which consists of Ag-modified CuBi₂O₄ nanorods and WO₃ nanoparticles decorated on single-layer graphene oxide (SL-GO) sheets, targeting both significantly enhanced methylene blue (MB) adsorption and photodegradation. The Ag-CuBi₂O₄/WO₃/SL-GO nanocomposite was synthesized via combined hydrothermal/ultrasonication methods. XRD, SEM, EDX, FTIR, XPS, PL, and Raman techniques confirm its successful preparation. The analyses demonstrated a substantial enhancement in MB adsorption and near-complete MB photodegradation (99.5 %) under visible light, with a notably high kinetic rate constant (0.0319 min⁻¹). Its adsorption capacity was also 4–10 times larger than that of individual components and binary nanocomposite material. The enhanced performance is primarily ascribed to the reduced band gap, high surface area and exceptional electron conductivity of SL-GO, efficient charge separation, reduced electron-hole recombination, enhanced visible light absorption capacity, and synergistic integration of Ag-CuBi₂O₄/WO₃ and SL-GO features. In addition, the nanocomposite was non-genotoxic, which assures its safe use in environmental applications. This study presents a promising and low-energy approach for water remediation, highlighting the potential of the hybrid Ag-CuBi₂O₄/WO₃/SL-GO photocatalyst for sustainable environmental applications and can guide future designs for the removal of diverse pollutants.