Perovskite engineering for efficient oxygen evolution reaction through iron and silver doping

This study investigates the effects of Fe and Ag doping on the structure, surface properties, and electrochemical performance of a Ba-containing perovskite oxide for the oxygen evolution reaction (OER). Three catalysts, LBC, Fe-doped LBC (LBCF), and Ag-impregnated LBCF (LBCF-A), were synthesized using sol-gel and wet impregnation methods. Their physicochemical properties were characterized using XRD, FESEM, HRTEM, ICP, FTIR, and XPS. Electrochemical evaluations, including linear sweep voltammetry (LSV), Tafel analysis, and turnover frequency (TOF), were conducted to assess OER performance. Among these, LBCF-A exhibited the best OER activity, with an overpotential of 317 mV at 10 mA.cm^-2, a Tafel slope of 101 mV.dec^-1, and a significantly higher TOF. The enhanced performance is attributed to Fe-induced modulation of Co oxidation states, formation of oxygen vacancies, and Ag-mediated surface modifications that enriched surface hydroxyls (OH^-), O₂, and H₂O. These synergistic effects improved conductivity and charge transfer, making LBCF-A a promising candidate for efficient and cost-effective OER catalysis.