Research institute of Petroleum Industry (RIPI) Journal of Petroleum Research 2345-2900 35 1404-2 2025 06 22 Investigation of Different Immobilization Methods of TiO2-WO3 Nanocomposite over Kieselguhr for Photocatalytic Removal of Agricultural Herbicide Investigation of Different Immobilization Methods of TiO2-WO3 Nanocomposite over Kieselguhr for Photocatalytic Removal of Agricultural Herbicide 87 98 1497 10.22078/pr.2025.5464.3433 FA Rojiar Akbari Seneh Department of Chemical Engineering, Faculty of Engineering, University of Kurdistan, Sanandaj, Iran Farhad Rahmani Department of Chemical Engineering, Faculty of Engineering, University of Kurdistan, Sanandaj, Iran Maryam Moradi Department of Chemical Engineering, Faculty of Engineering, University of Kurdistan, Sanandaj, Iran Journal Article 2024 05 18 In the present study, the comparison of the potential of TiO2-WO3/Kieselguhr composite photocatalysts synthesized by different methods with the aim of finding the most effective immobilization method of TiO2-WO3 heterojunction nanoparticles were studied in the photodegradation of paraquat herbicide. For this purpose, TiO2-WO3 heterostructured photocomposites were synthesized via precipitation and solid-state dispersion (SSD) methods and characterized by XRD, FESEM, EDX, FTIR, PL and UV-Vis techniques. The characterization results alongside the confirmation of synthesis accuracy of samples show that the presence of Kieselguhr as a support of TiO2-WO3 heterojunction not only maintains the morphology and structure of semiconductors but also reduces the aggregation of TiO2 and WO3 nanoparticles, which causes a better interaction between the loaded active nanoparticles and the support. However, based on the XRD, FESEM and PL analyses, a better dispersion of semiconductors loaded on the support, a reduction in the number of surface agglomerates with a minimum Kieselguhr pores blocking, and a decrease in the of electron-hole pairs recombination rate in the precipitation synthesized sample were realized. Ultimately, by examining the performance of TiO2-WO3 heterostructured photocomposites synthesized via precipitation method under 2h UV irradiation and optimal operation conditions (5 ppm pollutant concentration and 1.5 g/L photocatalyst dosage), 84% of paraquat photocatalytic removal was obtained. In the present study, the comparison of the potential of TiO2-WO3/Kieselguhr composite photocatalysts synthesized by different methods with the aim of finding the most effective immobilization method of TiO2-WO3 heterojunction nanoparticles were studied in the photodegradation of paraquat herbicide. For this purpose, TiO2-WO3 heterostructured photocomposites were synthesized via precipitation and solid-state dispersion (SSD) methods and characterized by XRD, FESEM, EDX, FTIR, PL and UV-Vis techniques. The characterization results alongside the confirmation of synthesis accuracy of samples show that the presence of Kieselguhr as a support of TiO2-WO3 heterojunction not only maintains the morphology and structure of semiconductors but also reduces the aggregation of TiO2 and WO3 nanoparticles, which causes a better interaction between the loaded active nanoparticles and the support. However, based on the XRD, FESEM and PL analyses, a better dispersion of semiconductors loaded on the support, a reduction in the number of surface agglomerates with a minimum Kieselguhr pores blocking, and a decrease in the of electron-hole pairs recombination rate in the precipitation synthesized sample were realized. Ultimately, by examining the performance of TiO2-WO3 heterostructured photocomposites synthesized via precipitation method under 2h UV irradiation and optimal operation conditions (5 ppm pollutant concentration and 1.5 g/L photocatalyst dosage), 84% of paraquat photocatalytic removal was obtained. https://pr.ripi.ir/article_1497_55c567fd4395ecef6d936cf77b8d5b2b.pdf