MnCoP/(Co,Mn)(Co,Mn)2O4 nanocomposites for all-solid-state supercapacitors with excellent electrochemical energy storage

Abstract

In this study, MCP/MCO nanocomposites were prepared by hydrothermal + annealing + phosphating treatment method. and they exhibited excellent electrochemical properties as supercapacitor electrode material with a specific capacity of 220.4 F/g at a current density of 0.1 A/g in 6 M KOH solution and good cycling stability. Aqueous MnCoP/(Co,Mn)(Co,Mn) 2 O 4 //active carbon asymmetric supercapacitor demonstrate the high capacitance of 74.14 F/g at 0.1 A/g and maintained 85.75% of the initial capacitance after 10,000 GCD cycles at a current density of 0.5A/g. Especially, all-solid-state asymmetric supercapacitors assembled by MnCoP/(Co,Mn)(Co,Mn) 2 O 4 nanocomposites demonstrated the capacitance of 123.43 F/g at a current density of 0.5 A/g, an energy density of 132.3 Wh kg −1 at a power density of 503.4W kg −1 . When the all-solid-state supercapacitors were connected with different manners, constructing the supercapacitor arrays for practical applications. The supercapacitor arrays showed the typical continuous extension of voltage and increased current density, highlighting the promising practical applications of MnCoP/(Co,Mn)(Co,Mn) 2 O 4 nanocomposites to meet various output requirements in electrochemical enenrgy storage. • MCP/MCO nanocomposites were prepared by hydrothermal + annealing + phosphating treatment method. • The aqueous asymmetric supercapacitor (MCP/MCO//AC ASC) exhibited high energy storage capacity (specific capacitance of 74.14 F/g at a current density of 0.1 A/g), good rate performance and cycling stability (85.75% capacity retention after 10,000 cycles). • All-solid-state asymmetric supercapacitors assembled by MnCoP/(Co,Mn)(Co,Mn) 2 O 4 nanocomposites exhibit the capacitance of 123.43 F/g at a current density of 0.5 A/g, an energy density of 132.3 Wh kg −1 at a power density of 503.4 W kg −1 , good rate performance and cycling stability. • When the all-solid-state supercapacitors were connected with different manners, constructing the supercapacitor arrays for practical applications. The supercapacitor arrays showed the typical continuous extension of voltage (in series) or increased current density (in parallels). MnCoP/(Co,Mn)(Co,Mn) 2 O 4 nanocomposites were prepared by hydrothermal + annealing + phosphating treatment method and their electrochemical properties were investigated, systematically. Aqueous MnCoP/(Co,Mn)(Co,Mn) 2 O 4 //active carbon asymmetric supercapacitor demonstrate the capacitance of 74.14 F/g at 0.1 A/g and good rate performance and cycling stability(maintained 85.75 % of the initial capacitance after 10,000 GCD cycles at a current density of 0.5A/g). Furthermore, all-solid-state asymmetric supercapacitors assembled by MnCoP/(Co,Mn)(Co,Mn) 2 O 4 nanocomposites exhibit the capacitance of 123.43 F/g at a current density of 0.5 A/g, an energy density of 132.3 Wh/kg at a power density of 503.4 W/kg, good rate performance and cycling stability. Especially, the all-solid-state supercapacitors connected in series present excellent voltage extendtion capability and the ones assembled in parallel demonstrate outstanding capacitance retention capability, highlighting the promising practical applications of MnCoP/(Co,Mn)(Co,Mn) 2 O 4 nanocomposites to meet various output requirements in electrochemical enenrgy storage.