Lung-like gas supply for hydrogen oxidation reaction in fuel cell anode

ended

In researches about hydrogen oxidation reaction (HOR) at the anode of a fuel cell, most researchers concentrate on the intrinsic activity and stability of catalysts, while few researches study the gas diffusion effect in depth, which is however the rate-determine step for most HOR. Enlightened by the efficient lungs’ supply of oxygen to human with multistage bronchi and pulmonary alveoli, we plan to improve the hydrogen gas diffusion for HOR by constructing multistage superaerophilic gas channels (MSGC) in the catalyst layer (CL). Traditionally, to build gas channels in CL, people modify powder catalysts with aerophilic binder, which however cause aggregation and therefore hindered the transfer of electron and mass. Besides, part of the randomly made gas channels are closed that cannot transfer hydrogen actually. Thus, there are two challenges in MSGC construction: a solid and strong hierarchical micro-nano skeleton, that won’t aggregate, to support catalyst and channels, and a method to control the direction of the channels. Herein, we propose tungsten carbide nanoarrays (WC NA) as the skeleton for Pt catalyst and invent a vacuum-control method based on superwetting technology to direct the gas channels. Although WC nanoparticles have been proved promising as the substrate of Pt for HOR, WC NA has never been tried. Based on the novel structure, we will study the relationship between structure, gas diffusion, and HOR efficiency in depth. Targeting at the rate-determine step of HOR, we’re expecting a theoretical breakthrough in HOR, which will offer an alternative approach for making hydrogen anode in fuel cell industry.