Single‐Atom Cr‐N4 Sites Designed for Durable Oxygen Reduction Catalysis in Acid Media
Single‐atom catalysts (SACs) are attracting widespread interest towards the catalytic oxygen reduction reaction (ORR),among which Fe‐Nx SACs exhibit the most promising activity. However, Fe based catalysts suffer serious stability issue from oxidative corrosion via Fenton reaction. Herein, using metal organic framework as anchoring matrix, we for the first time obtained pyrolyzed Cr/N/C SACs for ORR, where the atomically dispersed Cr are confirmed in Cr‐N4 coordination structure. The Cr/N/C catalyst exhibits excellent ORR activity with optimal half‐wave potential of 0.773V versus RHE. More excitingly, the Fenton reaction is substantially restrained and therefore the final catalysts show superb stability. This work proposes an innovative and robust active site for ORR, which opens a new route to circumvent the stability issue regarding the non‐noble metal ORR catalysts.
Source:: Angewandte Chemie Int. edition