To solve the growing energy issues, significant efforts have been focused on the search of earth-abundant elements that can provide multifunctional behavior for both energy generation and storage. Due to the low-cost and rich chemical nature, transition metal oxide nanostructures have been used in the fabrication of energy devices, such as fuel cells and lithium batteries. In this work, nickel, cobalt and iron molybdates were synthesized via a simple hydrothermal method in order to fabricate electrodes for oxygen evolution reaction (OER) and a supercapacitor. FeMoO₄ required an overpotential of 294 mV to achieve a current density of 10 mA/cm2 for oxygen evolution reaction, which is lower than the overpotential required for NiMoO₄ and CoMoO₄ to do the same process. For the energy storage properties, the highest specific capacitance was achieved by FeMoO₄ electrode (11.5 F/cm2 at a current density of 1 mA/cm2). Galvanostatic charge-discharge measurements were performed and showed a better discharge time for iron molybdate. The capacitance retention and coulombic efficiency exhibited excellent performance over 5,000 cycles. In conclusion, molybdates, mainly FeMoO₄, could be a promising material for the advancement of energy generation and storage devices.
Zequine, Camila; Kahol, Pawan K.; and Gupta, Ram K., "Molybdenum Oxides for Energy Generation and Storage Using Efficient Clean Method" (2019). Posters. 65.