Antiperovskite Intermetallic Nanoparticles for Enhanced Oxygen Reduction. Issue 5 (17th December 2019) - Zhang, Hao
Abstract: Antiperovskite Co3 InC0.7 N0.3 nanomaterials with highly enhanced oxygen reduction reaction (ORR) performance were prepared by tuning nitrogen contents through a metal–organic framework (MOF)‐derived strategy. The nanomaterial surpasses all reported noble‐metal‐free antiperovskites and even most perovskites in terms of onset potential (0.957 V at J =0.1 mA cm −2 ) and half‐wave potential (0.854 V). The OER and zinc–air battery performance demonstrate its multifunctional oxygen catalytic activities. DFT calculation was performed and for the first time, a 4 e − dissociative ORR pathway on (200) facets of antiperovskite was revealed. Free energy studies showed that nitrogen substitution could strengthen the OH desorption as well as hydrogenation that accounts for the enhanced ORR performance. This work expands the scope for material design via tailoring the nitrogen contents for optimal reaction free energy and hence performance of the antiperovskite system. Abstract : ORR or nothing : Cobalt is an oxygen reduction reaction (ORR) inert metal, however, it can now be activated for this reaction by forming the intermetallic antiperovskite phase Co3 InC0.7 N0.3 . Tailoring the C/N ratio strengthens both the desorption and the hydrogenation step thus optimizing ORR activity.