A rational synthesis of hierarchically porous, N-doped carbon from Mg-based MOFs: understanding the link between nitrogen content and oxygen reduction electrocatalysis

摘要: Controlled mixtures of novel Mg-based metal–organic frameworks (MOFs) were prepared, with H+ or K+ as counterions. A linear relation was found between synthesis pH and K/H ratio in the resultant mixture, establishing tunability synthesis. Upon pyrolysis, these precursor yield nitrogen-doped, hierarchically porous carbons, which have good activity towards oxygen reduction reaction (ORR) at 13. The nitrogen content varies significantly along homologous carbon series (>400%, 1.3 at% to 5.7 at%), a much greater extent than microstructural parameters such surface area graphitization. This allows us isolate positive correlation electrocatalytic ORR this class metal-free, N-doped, carbons.