A flower‐like α‐phase nickel‐cobalt‐manganese hydroxide modified with two‐dimensional Ti₃C₂ for high performance hybrid supercapacitors

Abstract

A flower-like nickel-cobalt-manganese hydroxide (NiCoMn-OH) modified with two-dimensional Ti 3 C 2 nanoflakes has been synthesized via simple one-step hydrothermal method. The NiCoMn-OH/Ti 3 C 2 composite exhibits a high specific capacity of 670.3 C/g at a specific current of 1 A/g, higher than 614.6 C/g for NiCoMn-OH and 8.9 C/g for Ti 3 C 2 at the same conditions. The improved electrochemical performance is due to that Ti 3 C 2 is absorbed and distributed on the surface of NiCoMn-OH in its situ synthesis process and enhances its electro-activity.The hybrid supercapacitor based on NiCoMn-OH/Ti 3 C 2 and RGO shows high specific capacity of 177.5 C/g at 0.5 A/g and 103.1 C/g at 10 A/g, retaining 93.28% of initial capacity after 5000 charge/discharge cycles at 7 A/g. The hybrid supercapacitor also displays extraordinary specific energy of 41.15 Wh/kg at a specific power of 375 W/kg and 21.46 Wh/kg even at 7.5 kW/kg.