Biomass-derived precious metal-free porous carbon: Ca-N,P-doped carbon materials and its electrocatalytic properties

The search for non-noble metal catalysts drive from biomass materials for oxygen reduction reactions (ORR) is highly desirable but challenging. Here, we have designed and synthesized three-dimensional hierarchical porous Ca-modified nitrogen and phosphorus co-doped carbon materials (Ca@NP6C4) derived from biomass hydrogel. Notably, the resulting Ca@NP6C4 material has high content of nitrogen (29.71 wt%),and relatively high content percentage of pyridinic and graphitic nitrogen. As an efficient non-noble metal electrocatalyst, Ca@NP6C4 exhibits a high onset potential (0.94 V vs RHE) and a four-electron pathway for oxygen reduction reaction as well as good durability and outstanding methanol poisoning tolerance. Besides, it also performs as a good support for Pt particles (NPs). Pt/Ca@NP6C4 catalyst displayed remarkable catalytic performance and high stability for methanol electrooxidation reaction in acid medium. This work provides a feasible approach to develop cost-effective and highly efficient non-precious metal electrochemical catalysts for oxygen reduction. (C) 2021 Elsevier B.V. All rights reserved.