Munasir Munasir, Soffin Harjasa Setiawan Okto, Nuhaa Faaizatunnisa, Muhammad Naufal Ariesta, Evi Suaebah, Mita Anggaryani, Ahmad Taufiq, Markus Diantoro, Yuda Prima Hardianto
Photodegradation is gaining attention as an effective approach for treating wastewater, especially for removing organic pollutants. In this work, we present an environmentally friendly green route to synthesize titanium dioxide (TiO₂) nanoparticles using Syzygium cumini leaf extract as a reducing and capping agent. Graphene oxide (GO) was prepared using Hummers’ method, and the TiO₂/GO nanocomposite was subsequently formed via a hydrothermal process. This green synthesis route offers a sustainable, non-toxic, and low-cost alternative to conventional methods. The materials were thoroughly characterized using XRD and FTIR to confirm their composition, SEM and TEM for morphological analysis, and UV-DRS to study their optical properties. The photocatalytic performance was evaluated through the degradation of methylene blue (MB) in water. The TiO₂/GO nanocomposites achieved an impressive 99.2 % degradation of methylene blue (MB) after 240 min. Good stability was maintained over three reuse cycles, with a degradation efficiency of 70.7 % and a rate constant of 0.01167 h⁻¹, following a first-order kinetic model. The computational investigation of the molecular orbitals of MB also helps to elucidate its photoinduced reactivity, offering valuable insights into the underlying pathways of the photocatalytic process. These results highlight the potential of green-synthesized TiO2/GO nanocomposites as efficient and reusable photocatalysts for water purification. © 2026 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.
Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Surabaya, Kampus Ketintang, Surabaya, 60231, Indonesia; Department of Chemistry, Faculty of Science and Data Analytics, Institut Teknologi Sepuluh Nopember, Jl. Arif Rahman Hakim, Kampus ITS Keputih-Sukolilo, Surabaya, 60111, Indonesia; Department of Product & Application Development, LyondellBasell Advanced Polyolefins, Pasuruan, Indonesia; Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Malang, Jl. Semarang, Malang, 65145, Indonesia; Department of Physics, King Fahd University of Petroleum & Minerals (KFUPM), PO Box 13 5047, Dhahran, 31261, Saudi Arabia
