Amorphous NiMoP patchy nanospheres enfolded by rGO sheets for efficient oxygen evolution reaction and durable supercapacitor electrodes

With the growing issues of energy crisis, global warming, and environmental pollution, a lot of attention has been attracted to the development of clean and renewable energy storage/conversion systems, such as fuel cells, supercapacitors, and batteries. Herein, the nickel molybdenum phosphide-based patchy nanospheres (NMP PNSs) enfolded by reduced graphene oxide (rGO) sheets directly grown on nickel foam were prepared by a facile hydrothermal method. Moreover, the morphologies, electrochemical characteristics, and oxygen evaluation reaction (OER) properties of the synthesized materials were systematically studied. The NMP PNSs-rGO electrode material revealed enhanced specific capacity as compared to the pristine NMP PNSs electrode. Furthermore, the optimized NMP PNSs-rGO electrode delivered an excellent specific capacity of 158 mAh g⁻¹ (1135 F g⁻¹) at a current density of 1 A g⁻¹. The fabricated pouch-like hybrid supercapacitor (HSC) device showed improved rate capability, power density, and energy density as well as long-term cycling stability. Also, various portable electronic devices were powered up using the HSC devices to test real-time applications. In addition, the NMP PNSs-rGO material exhibited extremely higher catalytic properties when compared to the other prepared materials in an alkaline medium. This investigation is advantageous to the more in-depth study on effective multi-functional electrode materials in supercapacitors and OER fields. Distinctly, the obtained results strongly suggest that the NMP PNSs-rGO electrode could be a promising candidate for energy applications.