Facile synthesis of Co2P2O7 nanorods as a promising pseudocapacitive material towards high-performance electrochemical capacitors

Abstract

In the present work, we developed an efficient one-step template-free strategy to fabricate intriguing one-dimensional (1D) Co₂P₂O₇ nanorods (NRs) at room temperature, and utilized the unique monoclinic Co₂P₂O₇ NRs as an excellent electrode material for high-performance pseudocapacitors using 3 M KOH as an electrolyte. Strikingly, the as-synthesized 1D Co₂P₂O₇ NR electrode delivered a specific capacitance (SC) of 483 F g⁻¹ at 1 A g⁻¹, and even at 402 F g⁻¹ a high current loading of 10 A g⁻¹. And the SC retention of ∼90% over continuous 3000 charge–discharge cycles at a current density of 6 A g⁻¹confirmed its stable long-term cycling ability at high current density. More significantly, the underlying electrochemical energy-storage mechanism of the Co₂P₂O₇ NR electrode in alkaline KOH aqueous solution was tentatively proposed. And the appealing strategy was proposed for future exploration and development of other low-cost pseudocapacitive materials for next-generation ECs.