A Microfluidic Reactor for Solar Fuel Production from Photocatalytic CO₂ Reduction

Photocatalytic CO₂ conversion into usable chemical fuels is considered as an ideal way to tackle problems such as energy shortage and global warming simultaneously. In this "kill two birds with one stone" approach, CO₂ is used as feedstock and abundant solar light as energy source. For this purpose, a photocatalytic micro-reactor was designed in order to overcome problems of conventional photo-reactors including low surface-area-to-volume ratio, poor mass and photon transfer. Common materials such as Fluorine-doped Tin oxide (FTO) glass, Polymethyl methacrylate (PMMA) and surlyn that widely used in photoelectrochemical and solar cells were employed for the fabrication of the reactor. The feasibility and performance of the proposed reactor was tested in the challenging case of photocatalytic CO₂ reduction on TiO₂ thin film. The experimental results confirmed that one of the main products of CO₂ reduction was methanol. Maximum methanol concentration reached 162 μM at a flow rate of 120 μL/min.