Bifunctional electrocatalytic reduction performance of nitrogen containing biomass based nanoreactors loaded with Ni nanoparticles for oxygen and carbon dioxide

Abstract

Abstract In the face of increasing energy demand, the transformation approach that combines energy restructuring and environmental governance has become a popular research direction. As an important part of electrocatalytic reactions for gas molecules, reduction reactions of oxygen (ORR) and carbon dioxide (CO2RR) are very indispensable in the field of energy conversion and storage. However, the irreversibility of electrode materials is a constant challenge in electrocatalysis. However, the non-interchangeability and irreversibility of electrode materials have always been a challenge in electrocatalysis. Hereon, nickel and nitrogen doped biomass carbon-based materials (Ni/N-BC) was prepared by high temperature pyrolysis using agricultural waste straw as raw material. Surprisingly, it has abundant active sites and specific surface area as both electrocatalytic catalysts for ORR and CO2RR. The three-dimensional porous cavity structure could not only provide a strong anchoring foundation for the active site, but also facilitate the transport and enrichment of reactants around the site. In addition, temperature modulation during the preparation process also optimized the composition and structure of biomass carbon and nitrogen. Benefit from above structure and morphology advantages, Ni/N-BC-800 exhibits the highest electrocatalytic activity for both ORR and CO2RR simultaneously. More specifically, Ni/N-BC-800 exhibits strong ORR activity in terms of initial potential and half wave potential, while also enabling the production of CO products under highly selective conditions. The research results provide ideas for the development and design of electrode materials and green electrocatalysts, and also expand new applications of agricultural waste in fields such as energy conversion, environmental protection, and resource utilization.