| 초록 |
Transition metal carbides attract attention as an alternative for the noble metal electrocatalysts. In particular, Molybdenum carbide(MoxC) shows high potential as an efficient hydrogen evolution reaction(HER) electrocatalyst. However, MoxC has inherent limitations for HER due to the low density of active site and nonideal hydrogen binding energy. Here we report the synthesis process using an interaction mediator(IM) to increase active site density for high HER activity. IM helps to regulate the interaction between PEO-b-PS template and Mo source to make mesoporous nanostructures. Mo’s valence state is adjusted by the environment around Mo which is controlled by heat treatment under air before thermal treatment at 1100℃. As a result, MoxC shows a large increment of HER activity. Additionally, we newly identified a volcano-type correlation between HER activity and Mo valence. Our work can be applied to various carbide and Mo-based catalysts with valence state and HER relationship. |
