Different morphologies of MnO2 grown on the graphene@nickel foam electrode for supercapacitor application

Uniformly coated highly porous graphene/MnO2foams for flexible asymmetric supercapacitors

“…In fact, the coating of three-dimensional carbon structures with micrometer-sized pores (<10 μm) using these techniques has not been reported so far since the small pore volume easily leads to a depletion of the pseudocapacitive element in the electrolyte yielding a nonuniform coverage of the 3D structure. The published high quality GFs coated with pseudocapacitive materials [15,16,[21][22][23][24][25][26][27][28][29][30] are all based on mm thick commercially available metal substrates with pore sizes larger than 200 μm and do not show pores in the lower micrometer range [31], which would complicate a uniform coverage of the GF current collector. Furthermore, they suffer from low volumetric capacitances and, thus, low energy densities, since their large pores do not contribute to the energy storage, strongly compromising their use in real application.…”

Supercapacitor device performances of polycarbazole/graphene and polycarbazole/nanoclay/graphene nanocomposites

“…Carbazole is a cheap monomer, which has good charge carrier properties so addition with other carbon based materials can be used in many applications such as solar cells [12,13], (bio)sensors [14][15][16] and supercapacitors [17][18][19][20]. Conducting polymers, such as polyaniline [21], polythiophene [22], polycarbazole [23] and poly(N-vinylcarbazole) [24], polymethylcarbazole [25], and nanomaterials, such as RuO 2 [26], MnO 2 [27], nanoclay [28] and TiO 2 [29], are pseudo-capacitive materials that have relatively high specific capacitance. However, limited poor stability was obtained for these materials owing to the redox reaction results in degradation problems [30][31][32].…”