This project was conducted to investigate how to maximise the efficiency for photodecomposition based methanal scrubbers. The project focuses on using titanium dioxide Nanoparticles (NPs) in combination with chlorophyll (Chl) to achieve photodecomposition. In order to explore different factors that can affect the decomposition rate, namely, size of photocatalyst, temperature and phase of photocatalyst. It was found that a setup with solid supported TiO2 – Chlorophyll Nanoparticles is superior at decomposing methanal. Although inferior in terms of decomposition rate, TiO2 – Chlorophyll Nanoparticles suspended in 6:4 DMSO/H2O also has compelling advantages, specifically enforced contact between catalyst and methanal, and a higher water source to support the formation of free radicals.