Solution-free self-assembled growth of ordered tricopper phosphide for efficient and stable hybrid supercapacitor

• Published in: Energy storage materials Vol. 39; p. 194
• Main Authors: Chodankar, N. R., Shinde, P. A., Patil, S. J., Hwang, S. -K, Raju, G. S. R., Ranjith, K. S., Dubal, D. P., Huh, Y. S., Han, Y. -K
• Format: Journal Article
• Language: English
• Published: 01-08-2021
• Subjects: Dry electrode; Energy efficiency; Hybrid supercapacitor; Self-assembly; Solution free
• ISSN: 2405-8297; 2405-8289; 2405-8289
• DOI: 10.1016/j.ensm.2021.04.023

Herein, a solution-free dry strategy for the growth of self-assembled ordered tricopper phosphide (Cu3P) nanorod arrays is developed and the product is employed as a high-energy, stable positive electrode for a solid-state hybrid supercapacitor (HSC). The ordered Cu3P nanorod arrays grown on the copper foam deliver an excellent specific capacity of 664 mA h/g with an energy efficiency of 88% at 6 A/g and an ultra-long cycling stability over 15,000 continuous charge–discharge cycles. These electrochemical features are attributed to the ordered growth of the Cu3P nanorod arrays, which offers a large number of accessible electroactive sites, a reduced number of ion transfer paths, and reversible redox activity. The potential of the Cu3P nanorod arrays is further explored by engineering solid-state HSCs in which the nanorods are paired with an activated carbon-based negative electrode. The constructed cell is shown to convey a specific energy of 76.85 Wh/kg at a specific power of 1,125 W/kg and an 88% capacitance retention over 15,000 cycles. Moreover, the superior energy storing and delivery capacity of the cell is demonstrated by an energy efficiency of around 65%. The versatile solution-free dry strategies developed here pave the way towards engineering a range of electrode materials for next-generation energy storage systems. © 2021 Elsevier B.V.