Green synthesis and characterization of La-doped ZnO nanoparticles using pineapple peel extract: a sustainable approach to improve functional properties

Aim: The aim of this study is to synthesize and characterize the more efficient photocatalyst [zinc oxide nanoparticles (ZnONPs)] via the addition of dopant lanthanum (La) and pineapple peel extract. Pineapple peel as a green source consists of bioactive compounds that work as a capping agent and reducer for our La-doped ZnONPs (La-ZnONPs) and shield against the aggregation of nanoparticles. In addition, this study evaluates the influence of La doping on their structural and optical properties for photocatalytic applications. Methods: La-ZnONPs were modified and fabricated efficiently with the simple co-precipitation method with pineapple extract in this research work. The materials (La-ZnONPs) were thoroughly characterized by various spectroscopic techniques like X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), scanning electron microscopy-energy dispersive X-ray (SEM-EDX), ultra-violet visible (UV-Vis) spectroscopy and Brunauer-Emmett-Teller (BET) analysis. Results: This study effectively demonstrates the effect of concentration of La dopant on the La-ZnONPs fabrication such as elevation of La concentration from 1% to 3% in ZnO results in an augmentation of crystallite size (from 27.25 to 21.27 nm), accompanied by a corresponding shift in bandgap values (3.21 to 3.11 eV) along with surface area, and induces a morphological transformation after treatment. Conclusions: It was concluded that combining La doping with a green synthesis route provides an environmentally sustainable pathway for producing ZnO-based nanomaterials with improved functional properties.