Investigation of Competitive Photocatalytic Activity of Copper Oxide Nanofractals

Nanofractals (NFRs) have garnered attention due to their increased active sites relative to the overall surface available befitting fast catalytic applications. The growth of copper oxide (CuO) NFRs mediated by propolis and its effect on photocatalysis in aqueous media have been investigated. The transmission and scanning electron microscopy studies corroborate the growth of CuO nanofractal structures. The fractal dimension, measured via Bouligand‐Minkowski fractal theory using boxcounting methods, is (1.75 ± 0.01), indicating diffusion‐limited aggregation as the primary growth mechanism. The thermo‐gravimetric and differential thermal analyses demonstrate the thermal stability and chemical purity of the synthesized samples. The X‐ray diffraction, Raman scattering, and X‐ray photoelectron spectroscopy investigations confirm the monoclinic crystalline phase with Cu ²⁺ valence state, lattice oxygen (O ₂ ) ²⁻ , and interstitial oxygen vacancy/defect states. The optical absorption and luminescence characterizations, reveal a broad absorption band and defects/vacancies dominated radiative transitions in the spectral range 300–700 nm. The photocatalytic performance of CuO nanofractal on methylene blue (MB) dye shows a high and competitive catalytic rate (0.026 min ⁻¹ ). The ANOVA (analysis of variance) statistical analysis illustrates the significant effect of catalyst dose and dye concentration on the dye degradation rate. This study asserted it fits cost‐effective and eco‐friendly water purification applications.