Influence of carbon substrate on the electrochemical performance of carbon/manganese oxide hybrids in aqueous and organic electrolytes

Abstract

The carbon substrate has an important influence on the electrochemical performance of manganese oxide/carbon supercapacitors. Stable performance further requires asymmetric cell design in organic and aqueous electrolytes.

Design of Carbon/Metal Oxide Hybrids for Electrochemical Energy Storage

“…Carbon onions provided good conditions for homogenous deposition of birnessite‐type manganese oxide, whereas blocking of internal surface area was observed for activated carbon. However, considering that the hydrothermal approach is less precise compared to ALD, the minimum accessible pore size was bigger, and a sealing of the activated carbon particles was already observed at lower mass loadings . The study further concluded that the degree of carbon onion graphitization had a substantial impact on the electrochemical properties of the hybrid materials.…”

“…The study further concluded that the degree of carbon onion graphitization had a substantial impact on the electrochemical properties of the hybrid materials. Carbon onions synthesized at 1700 °C yielded higher electrical conductivity than at 1300 °C, resulting in an improved rate handling of the carbon onion/manganese oxide hybrid electrodes in 1 m Na 2 SO 4 aqueous electrolyte …”

“…By this way, high conductivity, high specific surface area, and redox‐active surfaces are combined in one material. Common synthesis techniques to assure a homogenous mixing of both components include wet‐chemical approaches and non‐line‐of‐sight vapor deposition like atomic layer deposition or chemical vapor deposition . Yet, hybridization can also be realized from a device engineering point of view.…”

Influence of Nitrogen‐Doping for Carbide‐Derived Carbons on the Supercapacitor Performance in an Organic Electrolyte and an Ionic Liquid

“…Beyond the design of carbon materials with an optimized porosity, there are other ways to enhance the energy storage capacity of supercapacitors ,,. Examples include the use of ionic liquids, or redox electrolytes,, and the addition of a redox‐active material like metal oxides or heteroatom doping . Especially the use of ionic liquids as an electrolyte for supercapacitors is promising because the significantly enhanced potential window leads to a large increase of the specific energy (the latter scales with the square of the voltage) .…”

Vanadia–titania multilayer nanodecoration of carbon onions via atomic layer deposition for high performance electrochemical energy storage

“…28 Our study clearly demonstrated that the interparticle pore space of OLCs provides favorable conditions for a conformal and nanocrystalline vanadia lm growth via ALD. 22 Depending on the observed charge-voltage-prole, redox systems are categorized either as pseudocapacitors ("capacitorlike", exhibition of constant charge-vs.-voltage proles, e.g., MnO 2 , [29][30][31] RuO 2 , 32 MXene 33 ), or as battery-like devices (showing well-dened redox peaks; e.g., V 2 O 5 , 34,35 polyaniline 36 ). 37 In particular, vanadia has gained considerable attention as both a cathode material in lithium batteries 38 and a redox-active component in hybrid electrodes.…”