Gamal Sayed, Husam Salama, Salah Abumhara, Sawsan Al Obaidly, Mai Al-Qubaisi, Hilal Al-Rifai
Review of socioeconomic risk factors for cesarean births: a population-based study
Acta bio-medica : Atenei Parmensis
platinum pt stateoftheart catalyst oxygen reduction reaction orr high cost scarcity limit largescale use however usage pt reduces sufficiently low level critical barrier may overcome atomically dispersed metal catalysts high activity high atom efficiency possibility achieve goal herein report locally distributed atomic ptco nitrogencarbonbased catalyst denoted acoptnc high activity robust durability orr 267 times higher commercial ptc mass activity acoptnc shows high selectivity 4e pathway orr differing reported 2e pathway characteristic atomic pt catalysts density functional theory calculations suggest high activity originates synergistic effect atomic ptco located defected cn graphene surface mechanism thought arise asymmetry electron distribution around ptco metal centers well metal atoms coordination local environments carbon surface coordination results n8v4 vacancies n8 represents number nitrogen atoms v4 indicates number vacant carbon atoms within carbon shell enhances oxygen reduction reaction via socalled synergistic effect