Study on electrocatalytic performance of Sm doped AlFeO3 as an electrocatalyst for OER

Abstract

Perovskite oxides are considered as highly effective oxygen evolution reaction (OER) catalysts under alkaline environments, to promote the reaction kinetics, allowing for more flexible electron transmission. In this work, a nanoflakes-based Sm-doped AlFeO₃ material was produced using a simple hydrothermal approach to evaluate its catalytic properties for OER. The electrocatalysts were evaluated using several analytical techniques to investigate their crystallinity, surface area and morphology. However, the physical analysis shows that the material has nanoflakes-like morphology which provides effective channels for the transmission of electrons which results in an improved surface area (61.58 m² g⁻¹) as validated via Brunnauer Emmett Teller (BET) measurements. To address the redox behavior, different electrochemical characterizations were performed to confirm the durability as well as the minimal overpotential exhibited by the material. Thus, the study shows that the Sm-doped AlFeO₃ has the reduced Tafel gradient (32 mV dec⁻¹) and utmost endurance of 40 h, with an overpotential (η) of 188 mV. Moreover, the impedance study supports this concept that prepared material Sm-doped AlFeO₃ has better OER kinetics since it has a low R_ct value (0.26 Ω) which indicates effective charge transmission. This work promotes the catalytic ability of perovskite oxides and shows their immediate applications in the development of improved OER electrocatalysts and other energy-related applications.

Graphical Abstract