Synergistic effect of a bamboo-like Bi 2 S 3 covered Sm 2 O 3 nanocomposite (Bi 2 S 3 -Sm 2 O 3 ) for enhanced alkaline OER.

The availability of hydrogen energy from water splitting through the electrocatalytic route is strongly dependent on the efficiency, durability, and cost of the electrocatalysts. Herein, a novel Bi 2 S 3 -covered Sm 2 O 3 (Bi 2 S 3 -Sm 2 O 3 ) nanocomposite electrocatalyst was developed by a hydrothermal route for the oxygen evolution reaction (OER). The electrochemical properties were studied in 1.00 mol KOH solution after coating the target material on the stainless-steel substrate (SS). Physical analysis via XRD, FTIR, IV, TEM/EDX, and XPS revealed that the Bi 2 S 3 -Sm 2 O 3 composite possesses metallic surface states, thereby displaying unconventional electron dynamics and purity of phases. The Bi 2 S 3 -Sm 2 O 3 composite shows outstanding OER activity with a low overpotential of 197 mV and a Tafel slope of 74 mV dec -1 at a 10 mA cm -2 current density as compared to pure Bi 2 S 3 and Sm 2 O 3 . Meanwhile, the composite catalyst retains high stability even after 100 h of the chronoamperometry test. Thus, this work unveils a new avenue for the speedy flow of electrons, which is attributed to the synergetic effect between Bi 2 S 3 and Sm 2 O 3 , as well as enriched interfacial defects, which exhibit greater oxygen adsorption capability with improved electronic assemblies in the active interfacial region. In addition, the introduced porous structure in core-shell Bi 2 S 3 -Sm 2 O 3 provides extraordinary electrical properties. Thus, this article offers a realistic framework for electrochemical energy generation.