One dimensionally arranged CoMoO4 an electrocatalyst for methanol assisted hydrogen production and supercapacitor applications

Abstract

Energy crisis and environmental protection are primary concerns of modern societies. Electrocatalytic water splitting to produce hydrogen is an ideal protocol, but sluggish OER reduces the efficiency. In this regard, one-dimensionally arranged CoMoO₄ nanorods are developed and applied for MOR (an alternative to OER), HER, and supercapacitor applications. The electrocatalyst shows excellent response for multiple electrochemical applications. It delivers a current density of 10 mA/cm² at 1.64 V vs RHE for MOR, with a Tafel slope of 100.6 mV/dec. The electrocatalyst demonstrates the superiority of MOR by reducing the onset potential and overpotential by 150 mV and 60 mV, respectively, compared to OER. The CoMoO₄ electrocatalyst also shows good performance for HER, delivering a current density of 10 mA/cm² at a potential of −0.42 V vs RHE, with a Tafel slope of 107.2 mV/dec. The material exhibits excellent performance as a supercapacitor, delivering a specific capacitance of 117.84 F/g, an energy density of 5.89 Wh/kg and a power density of 316.82 W/kg at a current density of 1 A/g. The material also shows excellent stability for MOR (8000 s), HER (8000 s), and supercapacitor (500 CV cycles), retaining 67 %, 94 %, and 88.5 % efficiency, respectively, with excellent ECSA of 4.85 mF/cm².