Aktivitas Fotokatalitik Komposit TiO2-N/Zeolit yang Disintesis dengan Metode Hidrotermal

Abstract

Water pollution due to industrial waste, especially those containing dyes, is increasingly becoming a serious problem in many countries. Methylene Blue (MB) is a dye widely used in the textile industry and can pollute the aquatic environment. This study aims to evaluate the potential of TiO₂-N/Zeolite composites in MB photodegradation, focusing on the effect of nitrogen composition on the photocatalytic activity and physical characteristics of the material. TiO₂-N/Zeolite composites were synthesized using the hydrothermal method, with variations in urea concentration as a nitrogen precursor, resulting in three sample variants: TiO₂-N/Zeolite (1.5), TiO₂-N/Zeolite (3), and TiO₂ N/Zeolite (5). The material characteristics were analyzed using SEM-EDX, FTIR, UV-Vis DRS, and BET, and their photocatalytic activities were compared with TiO₂-N and TiO₂. The results showed that all variants of TiO₂-N/Zeolite composites had higher photocatalytic activity compared to TiO₂-N and TiO₂. This was due to the combination of photocatalytic and adsorption mechanisms in the TiO₂-N/Zeolite composites. The addition of zeolite increased the specific surface area of the composite to 20.381 m²/g, which increased the adsorption capacity and provided more active sites for photocatalytic reactions. The TiO₂-N/Zeolite (1.5) composite, with the lowest nitrogen composition, showed the highest photocatalytic activity (99%) in MB degradation. UV-Vis DRS analysis showed that the TiO₂-N/Zeolite composite had a lower band gap than TiO₂, with TiO₂ N/Zeolite (5) having the lowest band gap (3.311 eV). EDX characterization revealed the highest nitrogen composition in TiO₂-N/Zeolite (5), which is 7.66%, while SEM analysis showed uneven morphology of TiO₂-N on the zeolite surface. FTIR indicated that nitrogen doping in TiO₂ occurred through an interstitial mechanism, which contributed to the narrowing of the band gap. This study suggests that TiO₂-N/Zeolite composites can be a more practical alternative for MB photodegradation than pure TiO₂.