Low-iridium doped single-crystalline hydrogenated titanates (H2Ti3O7) with large exposed {100} facets for enhanced oxygen evolution reaction under acidic conditions

Development of efficient and stable electrocatalysts for oxygen evolution reaction (OER) under conditions is desirable goal for commercializing proton exchange membrane (PEM) water electroyzer. Herein, we report iridium-doped hydrogenated titanate (Ir-HTO) nanobelts as a promising catalyst low-Ir content for the acidic OER. Addition of low-Ir (similar to 3.36 at%) into the single-crystalline HTO nanobelts with large exposed {100} facets significantly boost catalytic activity and stability for OER under conditions. The Ir-HTO outperforms the commercial benchmark IrO2 catalyst; an overpotential for vering 10 mA cm-2 current density was reduced to about 25% for the Ir-HTO. Moreover, the catalytic formance of Ir-HTO is positioned as the most efficient electrocatalyst for the acidic OER. An improved intrinsic catalytic activity and stability are also confirmed for the Ir-HTO through in-depth electrochemical characterizations. Therefore, our results suggest that low-Ir doped single-crystalline HTO nanobelts can promising catalyst for efficient and durable OER under acidic conditions.(c) 2023 Elsevier B.V. All rights reserved.

Automated summary

In this study, iridium-doped hydrogenated titanate (Ir-HTO) nanobelts were reported as a promising catalyst with low iridium content for the acidic oxygen evolution reaction (OER). The addition of low iridium significantly enhanced the catalytic activity and stability of single-crystalline HTO nanobelts with exposed {100} facets. Compared to the commercial benchmark IrO2 catalyst, Ir-HTO showed a 25% reduction in overpotential for current density of 10 mA cm-2. Furthermore, Ir-HTO exhibited the highest efficiency as an electrocatalyst for the acidic OER. Improved intrinsic catalytic activity and stability of Ir-HTO were confirmed through comprehensive electrochemical characterizations.