Tuning electronic correlations of ultra-small IrO2 nanoparticles with La and Pt for enhanced oxygen evolution performance and long-durable stability in acidic media

The rational design of electrocatalysts with active and long-durable characters applying in acidic proton exchange membrane electrolyzers is a spotlight for the sustainable energy storage. With the aim of tuning electronic structure of electrocatalysts and altering potential limiting step of the oxygen evolution reaction (OER), the ultra-small Pt, La co-doped IrO2 nanoparticles with average size of 2 nm highly dispersed on N-doped carbon (NC) was designed. Impressively, the representative Pt0.1La0.1-IrO2@NC exhibited the record performance toward OER in 0.5 M H2SO4 with a low overpotential of 205 mV (10 mA.cm(-2)), an extremely excellent stability of 135 h, and a fairly high TOF value of 5.71 s(-1) at eta = 280 mV. Theoretical calculations revealed that the co-doping of Pt, La into the lattice of IrO2 could rationally tune d band centers and lower the energy barrier for the potential-determining step (from *O to *OOH) toward OER.