A flower‐like α‐phase nickel‐cobalt‐manganese hydroxide modified with two‐dimensional Ti 3 C 2 for high performance hybrid supercapacitors

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.