Rational construction of ternary ZnNiP arrayed structures derived from 2D MOFs for advanced hybrid supercapacitors and Zn batteries

Exploiting nickel-based phosphide electrodes for next-generation high-performance supercapacitors and secondary batteries with high security has attracted great attentions. Herein, we fabricated binderless ZnNiP electrode based on Ni metal-organic framework and the optimized Zn-doping process, which achieved high electrochemical performance both in hybrid supercapacitor and Zn battery. Encouragingly, the addition of Zn source and the phosphating process make a component synergy with enhanced electronic conductivity, enriched electrochemical active centers and redox reactions. The ZnNiP-0.5 with sturdy construction exhibits a remarkable specific capacity and a good cycling stability in alkaline electrolyte. When assembled to hybrid supercapacitor, the installation delivers a maximum energy density of 67.4 Wh kg⁻¹, a maximum power density of 15.9 kW kg⁻¹, and outstanding cycling performance (88% retention after 10 000 cycles). Additionally, the fabricated Zn battery could achieve discharge voltage of~ 1.9 V, with an admirable energy density of 529.58 Wh kg⁻¹ and also shows the excellent durability (capacity retention of 91.6% after 3000 cycles). This work offers a feasible route and provides a certain guiding significance for the reasonable design of binder-free electrodes with delicate structures and compositions, which may inspire new significative findings of building electrodes for high-security hybrid supercapacitors and alkaline batteries.