Eco-friendly Synthesis of Cu₁₁O₂(VO₄)₆ Nanoparticles via Linum usitatissimum for Photocatalytic Degradation of Rose Bengal Dye and Photoluminescence Studies

The development of easily synthesized and high-efficiency semiconductor nanomaterials (NMs) is crucial for addressing environmental and energy challenges while promoting sustainable solutions in green chemistry and renewable energy. In this research, copper vanadate (Cu₁₁O₂(VO₄)₆) nanoparticles (NPs) are synthesized by the green combustion method using flaxseed (Linum usitatissimum) powder as green fuel. The obtained Cu₁₁O₂(VO₄)₆ NPs were characterized using techniques including XRD, FT-IR, PL, UV–Vis, SEM, EDAX, TEM, and XPS. XRD analysis exhibits an average crystallite size of 52 nm and a triclinic phase structure. The SEM data reveal the almost rectangular-shaped structure of Cu₁₁O₂(VO₄)₆ NPs. The optical band gap of Cu₁₁O₂(VO₄)₆ NPs was 2.4 eV. This smaller band gap allows the Cu₁₁O₂(VO₄)₆ NPs to absorb a wider range of visible light wavelengths, resulting in enhanced photocatalytic activity. For the first time, the luminescence properties of the Cu₁₁O₂(VO₄)₆ NPs were studied, and they exhibited blue-green light emission due to the charge transfer phenomena in the VO₄ tetrahedra, making it a promising material for various optoelectronic applications. They can also be employed as fluorescent materials for latent fingerprinting applications in future studies. Cu₁₁O₂(VO₄)₆ NPs showed excellent photocatalytic activities for the degradation of anionic Rose Bengal dye with 91% efficiency in an aqueous solution under visible light radiation. The degradation efficiency was examined by varying the amount of catalyst, dye concentration, and pH. The present study also investigated the reactive species and suggested the plausible degradation pathway by studying the scavenging and coumarin probes. In this process, this work contributes to the development of sustainable photocatalytic materials by utilizing natural resources for the synthesis of advanced NMs, paving the way for environmentally friendly applications in wastewater treatment.