Using aminopyrine as a nitrogen-enriched small molecule precursor to synthesize high-performing nitrogen doped mesoporous carbon for catalyzing oxygen reduction reaction

Abstract

With aminopyrine as a nitrogen-enriched small molecule precursor, a series of nitrogen doped carbon materials have been fabricated and explored as electrocatalysts for oxygen reduction reaction (ORR). The most active catalyst is a nitrogen doped carbon, which was prepared through a facile template-mediated pyrolyzing method using ferric nitrate (Fe(NO₃)₃·9H₂O) as an activation reagent along with nanoscaled silica as a sacrificial support (hereafter referred to as AP/SiO₂). The AP/SiO₂ is confirmed and identified as having highly active molecule catalytic centers for ORR, due to its possessing a porous, sponge-like and uniform structure with a super-large specific surface area of 932.68 m² g⁻¹. The AP/SiO₂ catalyst exhibited a high onset potential of 0.98 V, a half-wave potential of 0.82 V, and a high number of exchanged electrons (>3.8, close to four) in alkaline media. After 5000 continuous cycles, the material showed almost no negative shift with respect to the Pt/C material. Even in acidic medium, the AP/SiO₂ catalyst still showed much higher durability than Pt/C and a low yield of HO₂⁻. This work may have provided a new and simple route in the design and batch-synthesis of highly active and durable carbonaceous electrocatalysts for ORR.