Bamboo nanocellulose derived carbon loaded bismuth oxide: An effective nanocomposite for the solar photocatalytic degradation of malachite green

Abstract

Multi-component structural composites to tune the energy band structure of photocatalysts can achieve higher activity. In this study, flaky CNFC@Bi₂O₃ composites with high dispersibility were synthesised by a one-step calcination method using CNF as a template. The morphology and composition of the materials were characterized by SEM, XPS, XRD, PL, UV–vis DRS, TOC and LC-MS. The abundance of functional groups on the surface of the CNF-derived carbon induces the formation of this morphology, and the composite forms a direct Z-type heterojunction with good response in the visible region. The degradation of malachite green dye under visible light irradiation at 465 nm was found to be 758.64 mg g⁻¹ in 5 h. There was a significant increase in the degradation of malachite green dye compared to the composite BC@Bi₂O₃ prepared with bamboo cellulose(BC) as a template (425.76 mg g⁻¹). The findings indicated that CNFC@Bi₂O₃ dye removal exhibited the highest level of efficacy in comparison to CNF/0.3Bi (473.04 mg g⁻¹) and CNF/1.7Bi (545.52 mg g⁻¹). The best degradation of malachite green was found to occur in a weakly alkaline environment, with the order of effect of free radicals being: h⁺ > ·OH> ·O₂^-. The results indicate that the CNFC@Bi₂O₃ composites have great potential for dye wastewater degradation and environmental remediation, and provide a new idea for the synthesis of sustainable, eco-friendly and high performance photocatalysts.