PHOTOCATALYTIC REDUCTION OF CO_2 TO METHANOL USING CUO-TIO_2 /ACF CATALYST

• Main Author: Raihan Agis Pradana, Muhammad
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/73780
• Institution: Institut Teknologi Bandung

TiO2 is a commonly used photocatalyst because it has a low price and high stability. However, TiO2 has a high band gap (~3.20 eV) making it difficult to activate in visible light and easy for electron recombination to occur, so modifications to TiO2-based photocatalysts need to be made to improve photocatalytic performance. This study reviews the effect of the modified addition of CuO and activated carbon fiber support (ACF) on the performance of photocatalytic reduction of CO2 to methanol. Synthesis of the modified photocatalyst was carried out using the sol-gel method with titanium isopropoxide (TTIP) and copper (II) nitrate as precursors. The resulting variations in the synthesis of catalysts include: (1) ACF impregnated by TiO2 (TiO2/ACF) and (2) variations of TiO2/ACF impregnated by CuO at 1% and 3% by mass of CuO and TiO2 (1% CuO-TiO2/ACF & 3% CuO-TiO2/ACF). All of the synthesized photocatalysts were tested under UV-Vis and visible irradiation and compared with the performance of commercial TiO2. In addition, the effect of the reaction medium was also studied using ACN/H2O/TEOA for the best variation. XRD and SEM characterization has been carried out to prove the presence of TiO2 and CuO impregnation on the ACF surface. UV-DRS characterization showed a decrease in the band gap with the addition of CuO. Characterization of the BET instrument showed a 150-fold increase in surface area after using ACF support. Photocatalysts TiO2/ACF, 1% CuO-TiO2/ACF, and 3% CuO-TiO2/ACF respectively were able to produce 2.7 times higher methanol (~1.8 mmol/g catalyst); 3.6 times (~2.4 mmol/g catalyst); and 10.4 times (~6.9 mmol/g catalyst) than commercial TiO2 in visible light. The best variation was achieved by 1% CuO-TiO2/ACF with a methanol yield of 11.0 mmol/g catalyst under UV-Vis lighting. The best variation was then tested using the reaction medium ACN/H2O/TEOA and produced 27.1 mmol/g catalyst methanol.