Affiliation:
1. School of Chemical Engineering Chonnam National University 77, Yongbong‐ro, Buk‐gu Gwangju 61186 Republic of Korea
2. Ecole Normale Supérieure de Lyon CNRS Laboratoire de Chimie UMR 5182, 46 allée d'Italie Lyon F‐69364 France
3. Department of Chemistry Education Chonnam National University Gwangju 61186 Republic of Korea
Abstract
AbstractA promising strategy to boost electrocatalytic performance is via assembly of hetero‐nanostructured electrocatalysts that delivers the essential specific surface area and also active sites by lowering the reaction barrier. However, the challenges associated with the intricate designs and mechanisms remain underexplored. Therefore, the present study constructs a p–n junction in a free‐standing MnCo2O4.5@Ni3S2 on Ni‐Foam. The space‐charge region's electrical characteristics is dramatically altered by the formed p–n junction, which enhances the electron transfer process for urea‐assisted electrocatalytic water splitting (UOR). The optimal MnCo2O4.5@Ni3S2 electrocatalyst results in greater oxygen evolution reactivity (OER) than pure systems, delivering an overpotential of only 240 mV. Remarkably, upon employing as UOR electrode the required potential decreases to 30 mV. The impressive performance of the designed catalyst is attributed to the enhanced electrical conductivity, greater number of electrochemical active sites, and improved redox activity due to the junction interface formed between p‐MnCo2O4.5 and n‐Ni3S2. There are strong indications that the in situ formed extreme‐surface NiOOH, starting from Ni3S2, boosts the electrocatalytic activity, i.e., the electrochemical surface reconstruction generates the active species. In conclusion, this work presents a high‐performance p–n junction design for broad use, together with a viable and affordable UOR electrocatalyst.
Funder
National Research Foundation of Korea