Development of a Microfluidic Chip for Internal H2 and O2 Generation and Seperation Driven by Solar Light

Y. Pihosh, Y. Kajita, K. Mawatari and T. Kitamori
The University of Tokyo, JP

Keywords: microfluidic device, nano structured TiO2, integration, H2 and O2 generation

Summary:

Here, we report on the development of water splitting and the gas separation microfluidic device driven by the solar light energy for internal H2 and O2 generation. Firstly, we proposed two-dimensional nano-channels made in fused silica plate for efficient proton (H+) transport and separation. The maximum value of H+ diffusion coefficient was detected when the nano-channels size decreased to 180 nm, and the result was~5 times higher in comparison with the bulk value. Next, a photocatalytic water splitting system was developed and integrated directly into a microfluidic chip made in fused silica plate, with the TiO2 nanostructured photoanode, Pt cathode, nano-channels array as the H+ transfer system and hydrophobic modified micro-channels as the gas-liquid separation system, and the working principle was confirmed. Under solar light irradiation we observed the H2/O2 generation, which was confirmed by the GC-MS technique. In summary, we have proven the fundamentals of the light-driven micro fuel cell fabrication and verified the fuel generation and the gas liquid separation processes in the proposed microfluidic device.