Controlled preparation of Ni12P5 nanostructures with different morphology and their application in supercapacitors

Nickel phosphides are widely used as cathode materials for supercapacitors owing to their outstanding advantages such as high conductivity and electrochemical activity. In this work, the different microstructures of Ni12P5 are controllable synthesized based on a simple one-step hydrothermal method. The nanoparticle (NP), nanowire (NW), and nanomesh (NM) structures of Ni12P5 tend to be formed under ethanol, water, and ethylene glycol based on different polarity, separately. And then, these three kinds of Ni12P5 nanostructures were used as the cathode materials for supercapacitors. The specific capacitance of Ni12P5 NPs is about 955 F g(-1) at 1 A g(-1) (676 F g(-1) at 5 A g(-1)), which is higher than Ni(12)P(5 )NWs (871 F g(-1) at 1 A g(-1)) and Ni12P5 NMs (423 F g(-1) at 1 A g(-1)). The Ni(12)P(5 )NPs, NWs, and NMs have good cyclic stability with 81 %, 69 %, and 78 % of the initial specific capacitance after 1500 cycles at 5 A g(-1), respectively. Meanwhile, the Ni12P5 NPs//activated carbon hybrid supercapacitor provides an energy density of 122.3 Wh kg(-1) (vs. 0.75 kW kg(-1)) and power density of 7.5 kW kg(-1) (vs. 26.4 Wh kg(-1)), and good cycle stability. This work provides a novel technical basis for cathode materials of high-performance electrochemical energy storage devices.

Automated summary

This study synthesized different microstructures of Ni12P5 using a simple hydrothermal method and found that Ni12P5 NPs exhibit higher specific capacitance and good cyclic stability compared to Ni12P5 NWs and NMs. The Ni12P5 NPs//activated carbon hybrid supercapacitor shows high energy density and power density, as well as good cycle stability, providing a novel technical basis for high-performance electrochemical energy storage devices.