Synthesis and characterization of cadmium sulfide and titania photocatalysts supported on mesoporous silica for optimized dye degradation under visible light
Niloofar Fatemipayam, Narjes Keramati, Mohsen Mehdipour Ghazi
Abstract
This research presents a new and improved photocatalyst based on the synergistic effect of three components, CdS, TiO 2 , and MCM-41, applying statistical techniques to fine-tune degradation parameters for efficient Methylene Blue (MB) degradation. By creating a library of CdS/TiO 2 nanoparticles systematically loaded onto the mesoporous structure of MCM-41, with different loading percentages (5, 10, 15, 20, and 25% w/w), nanocomposites with high surface area and maximized optical properties were designed and analyzed using material characterization techniques including XRD, FTIR, XPS, UV-Vis DRS, TEM, FESEM, EDS, PL, and BET. Ideal performance was achieved from CdS/TiO 2 /MCM-41 (CTM) with a 15% w/w loading, which shows high photocatalytic performance at a neutral pH, reaching 45.6% MB degradation with only two 60-W lamps in 30 min. Furthermore, TOC analyses confirmed the effective degradation of MB and its intermediate. The reduction of the TOC (63%, 90 min), indicating successful mineralization of the pollutant. Response surface methodology was used to identify key factors that boost degradation performance, including pH, airflow, and photocatalyst concentration. This model, with a correlation coefficient of R 2 = 0.991 and a precision of 47.65, confirmed CTM’s potential as a scalable solution for wastewater treatment and pollution control.