Deciphering the Role of Spin-Polarization in Oxygen Evolution via Chiral Mixed Mn/Fe/Ni/Co-Based Transition Metal Oxide

Oxygen evolution reaction (OER) plays a crucial role in energy storage and conversion technologies. However, its higher overpotential challenges the scientific community to overcome it. Recent advancements in OER demonstrate that inducing spin-polarization at the anode either employing chiral molecular modification or magnetic substrate, augmentation of OER is possible. Adopting this idea, we evaluated the effect of chiral molecular modification of mixed-transition metal-based spinel oxide on the spin-polarized charge transfer during OER. Chiral molecular functionalization of the catalyst has been carried out using chiral analogs of phenylalanine, which enhances the stability and catalytic activity of the catalyst by controlling the electron's spin utilizing the chiral-induced spin selectivity (CISS) effect. The experimental results show that the chiral molecule integrated catalyst decreases the overpotential by ∼200 mV at 10 mA cm⁻² with respect to the achiral one. Moreover, it increases the current density by ∼2 times at 2.1 V (vs. RHE) and decreases hydrogen peroxide production significantly compared to its achiral analog. The results of these studies are explained by controlling the spin-polarization of the anodic current during water oxidation employing CISS effect. Hence, this study opens new avenues for enhancing the performance of the catalysts for sustainable energy applications utilizing spin-polarized charge transfer.