Characterization of ZnO Nanoparticles Pineapple Skin Extract (Ananas comosus L.) as Photocatalytic Activity

This research aims to determine the characteristics of ZnO nanoparticles as a photocatalytic agent. Synthesis of ZnO nanoparticles using green synthesis method from pineapple peel extract, whose results were characterized by X-ray Diffraction, Fourier Transform Infra-red, Field Emission-Scanning Electron Microscopy, Transmission Electron Microscopy, Raman spectroscopy, photoluminescence, and a photocatalytic activity assay. This research showed that ZnO nanoparticles had wurtzite phase, alcohol functional groups, and phenol O-H, C=C alkenes, C-O, C-N, and Zn-O. ZnO nanoparticles had a particle size of 20.04 nm, a polyhedral shape, and a band gap energy of 3.28 eV. The Raman active mode E₂ (High) at 439.05 cm^-1 confirmed the formation of pure phase wurtzite. Photoluminescence results indicated that two emission peaks at 392.07 nm and 595.07 nm were associated with defects such as oxygen and zinc vacancies. This study showed that ZnO nanoparticles were effective in photodegrading methylene blue dye within 180 minutes under UV light irradiation, with a known degradation value reaching 99.86%. In addition, ZnO nanoparticles as a catalyst are very stable and can be reused after five cycles. Thus, the synthesized ZnO nanoparticles can be applied effectively for environmental applications, namely as a photocatalyst in processing textile industry waste, especially for organic dye waste.