Montmorillonite geopolymer porous membrane as electrolyte framework for compression resistance supercapacitor application

Difunctional devices have great potential in the application of many areas, they can perform two functions simultaneously, and structural difunctional supercapacitor is one of them. The difunctional supercapacitor can carry out bearing capacity and storge electric energy, but it's difficult to keep the balance between bearing capacity and energy storage capacity. In this work, the montmorillonite based geopolymer has a compressive strength of 31.6 MPa after curing for 28 days, and a compressive strength of 30.5 MPa after repolymerization. We use the geopolymer as the framework, and inject 0.5 M Na2SO4 into the geopolymer to prepared a structural electrolyte. Then, the structural electrolyte membrane, electrodeposited MnO2, and an activated carbon are assembled into a difunctional supercapacitor. The maximum specific capacity reaches 2216.7 mF cm−2 at 1 mA cm−2 under 15 MPa, achieving a good balance between compressive strength and energy storage capacity.