SOLAR-DRIVEN PHOTOCATALYTIC CO2 CONVERSION TO METHANOL USING N-DOPED TIO2

• Main Author: Satyadharma, Kristian
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/67465
• Institution: Institut Teknologi Bandung

Carbon dioxide is a greenhouse gas which is harmful to the environment and to human’s life whose emission have always been increasing. Photocatalytic technology is one of the technologies utilized for reducing carbon dioxide emissions which has high potential due to the technology’s ability to convert carbon dioxide into value added chemicals like methanol. Titanium Dioxide (TiO2) is a photocatalyst that has been widely used however TiO2 has a quite large band gap ranging from 3,0 to 3,2 eV which can only be active in the UV spectrum region. This drawback can be overcome using several methods, one of those methods is nitrogen doping which can reduce the band gap and improve photocatalytic activity in the visible light region. The aim of this research is to synthesize nitrogen doped TiO2 to convert CO2 to methanol. The photocatalyst will then be characterized which comprises of measuring crystallinty using X-ray Diffraction (XRD), measuring morphology of catalyst using Scanning Electron Microscope (SEM), measuring the band gap energy using UV-vis diffuse reflectance spectroscopy (UV-vis DRS), and measuring the surface area and pore diameter using Braunanear, Emmelt, dan Teller (BET). Variation to find the optimum condition of photocatalysis includes varying the pH and the N/Ti molar ratio. The photocatalytic process will be conducted in a batch reactor for 3 hours. The product will then be analysed using gas chromatography to confirm the presence of methanol The results of this research are the photocatalyst is the anatase phase with a crystal size range of 83.5 to 91 nm through XRD results. UV-vis DRS results show that the photocatalysts doped with nitrogen has an extended light absorption and a band gap of 2,93 eV for N-TiO2 3%. BET results show that the N-TiO2 2% photocatalyst has the highest surface area of 120 m2/g. SEM results show that there is agglomeration of particles where the particle size range is 294 to 303 nm. The methanol concentration in the product is highest at pH 10 with N-TiO2 2% having the highest yield at 0.065 mol/g.cat.