A Ni-doped Mn-MOF decorated on Ni-foam as an electrode for high-performance supercapacitors

In this work, a one-step hydrothermal method is used to synthesize Ni-doped Mn-based organic framework material (Ni-doped Mn-MOF) on NF with 1,4,5,8-naphthalenetetracarboxylic acid (NTC) as ligand. Ni doping results in a more unique structure combining nanoblocks and nanosheets, which facilitates the contact between active sites and electrolyte ions and enhances electrochemical performance. Acting as the electrode material of supercapacitors, Ni-doped Mn-MOF shows a specific capacity of 779.6 C g−1 and a specific capacitance of 1676.6 F g−1 at 1 A g−1. Besides, the retention rate reaches as high as 75.9% after 10,000 cycles at 10 A g−1. Meanwhile, the as-prepared Ni-doped Mn-MOF//AC device shows a high specific capacitance of 361 C g−1 (225.6 F g−1) at 8 A g−1. By the way, the device exhibits an energy density of 74.75 Wh kg−1 at a power density of 7985.16 W kg−1 with 70.6% specific capacitance retention after 10,000 consecutive charge–discharge cycles at 10 A g−1. The ease of composite manufacturing demonstrates that Ni-doped Mn-MOF has potential applications as electrode materials for supercapacitor.