Metallic Metastable Hybrid 1T'/1T Phase Triggered Co,PSnS2 Nanosheets for High Efficiency Trifunctional Electrocatalyst.

Abstract

The development of trifunctional electrocatalyst for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) with deeply understanding the mechanism to enhance the electrochemical performance is still a challenging task. In this work, the distorted metastable hybrid-phase induced 1T'/1T Co,PSnS2 nanosheets on carbon cloth (1T'/1T Co,PSnS2 @CC) is prepared and examined. The density functional theoretical (DFT) calculation suggests that the distorted 1T'/1T Co,PSnS2 can provide excellent conductivity and strong hydrogen adsorption ability. The electronic structure tuning and enhancement mechanism of electrochemical performance are investigated and discussed. The optimal 1T'/1T Co,PSnS2 @CC catalyst exhibits low overpotential of ≈94 and 219.7mV at 10mA cm-2 for HER and OER, respectively. Remarkably, the catalyst exhibits exceptional ORR activity with small onset potential value (≈0.94V) and half-wave potential (≈0.87V). Most significantly, the 1T'/1T Co,PSnS2 ||Co,PSnS2 electrolyzer required small cell voltages of ≈1.53, 1.70, and 1.82V at 10, 100, and 400mA cm-2 , respectively, which are better than those of state-of-the-art Pt-C||RuO2 (≈1.56 and 1.84V at 10 and 100mA cm-2 ). The present study suggests a new approach for the preparation of large-scalable, high performance hierarchical 3D next-generation trifunctional electrocatalysts.