NiCo2O4 nanofeathers derived from prussian blue analogues with enhanced electrochemical performance for supercapacitor

Tuning the morphology and structure at nanoscale has become essential for the advancement of electrode materials. Here, the unique nanofeather arrays composing of 1D nanoneedles and 2D nanosheets are fabricated on nickle foam (NF) through a novel prussian blue analogues (PBA)-in-hydrothermal strategy with Ni-Co PBA as the precursor and template. Then the porous NiCo2O4 nanofeather arrays are formed after calcination, which are consisted of ultrasmall secondary nanoparticles with an average diameter of 3 nm, hence providing high porosity and rich active sites. Benefiting from the synergistic effect of NiCo2O4 1D nanoneedles and 2D nanosheets, the NF@NiCo2O4 nanofeathers electrode exhibits a high specific capacitance of 1797F g(-1) at 1 A g(-1) and superior rate capability with 85.7% capacitance retention (from 1 A g(-1) to 20 A g(-1)). Furthermore, a high energy density of 53.9 Wh kg(-1) at 801 W kg(-1), a high power density of 16 kW kg(-1) at 39.2 Wh kg(-1) and an outstanding cycling stability of 81.5% capacitance retention at 20 A g(-1) after 10,000 cycles are achieved in the assembled NF@NiCo2O4 nanofeathers//AC device. More importantly, this work provides an attractive strategy to combine PBA and classical hydrothermal process, as well as offers a new insight into the design of advanced energy materials.