Synthesis of Ni-Ca-O nanocomposite and study of their optical properties for photocatalytic degradation of textile dye and electrochemical detection of environmental pollutants

Ni-Ca-O nanocomposites were synthesized via a straightforward solution combustion process using acetamide as the fuel. Characterisation of the Ni-Ca-O nanocomposites using techniques such as UV-Vis (Ultraviolet Spectroscopy), EDX (Energy-Dispersive X-ray Spectroscopy), DRS (Diffuse Reflectance Spectroscopy), SEM (Scanning Electron Microscopy), XRD (X-ray Diffraction), and photoluminescence spectroscopy confirmed their crystalline structure, elemental composition, and optical properties. Photocatalytic experiments demonstrated efficient degradation of Coralene Blue BGFS dye under visible light, achieving a 65.3% efficiency at pH 2 with 0.6 g of catalyst and controlled UV irradiation shifted the optimal conditions to slightly alkaline environments (pH 8 and 9) with a 0.7 g dosage, achieving an improved maximum degradation of ~72%. Electrochemical analysis revealed the detection of catechol, hydroquinone, and bisphenol-A, with enhanced sensitivity at modified electrodes. Antimicrobial screening indicated dose-dependent activity against Aspergillus flavus (16.33 mm inhibition zone at 800μg), with minimal antibacterial effect. The efficient photocatalytic degradation of Coralene Blue BGFS dye under visible light and enhanced electrochemical sensitivity for the detection of catechol, hydroquinone, and bisphenol-A at modified electrodes, and dosedependent antifungal activity against Aspergillus flavus collectively demonstrate the multifunctional potential of the synthesized nanocomposites. The synthesized Ni-Ca-O nanocomposite nanoparticles demonstrate multifunctional applications for pollutant detection and dye removal.