Removing Cost Barriers to Template Carbon Synthesis for High-Performance Supercapacitors by Establishing a Zero-Emission Chemical Cycle from CO₂

Abstract

Template carbon (TC) is one of the most promising electrode materials for clean-energy devices (e.g., supercapacitors), but its application is hampered by the high cost of templates and carbon sources. Here, we report a green MgO template recycling technology that converts CO2 to high specific-surface-area TC by establishing a zero-emission chemical cycle at one-third the cost of nonrecycling methods. Up to 10 cycles of recycling demonstrate that the template’s dissolution and regeneration, as well as TC’s pore structure and physical properties, are extremely repeatable. Supercapacitors using symmetric TC electrodes deliver high-capacitance and -rate performances either in aqueous (KOH/H2O, >154 F g–1) or organic (Et4NBF4/AN, >140 F g–1) and ionic liquid (EMIMBF4, >178 F g–1) electrolytes, and ≈100% Coulomb efficiency, outperforming traditional commercial supercapacitors. This progress greatly reduces the cost of large-scale use of TC in supercapacitors and creates a sustainable link between CO2 reduction and clean-energy development.

Non‐Faraday Electrolyte Additives for Capacitance Boosting by Compression of Dielectric Layer Thickness: Organic Ferroelectric Salts

“…As compared with Micro‐C SCs, the addition of a small amount of DIPAP improves the mobility of electrolyte ions in the mesopores but not in the micropores (i.e., an enhanced response current density in the CV curve of Meso‐C electrodes in Figure S6a, Supporting Information). [ 31 ] The fact that ionic mobility is not a factor in the parallel plate capacitor's defining equation suggests that the increase in C areal may also be related to the microstructure of the DIPAP‐containing electrolyte or the properties of the carbon electrode in contact with the electrolyte.…”

Recent Advances of Modified Ni (Co, Fe)-Based LDH 2D Materials for Water Splitting

“…As one of the huge reserve resources, carbon-based materials have been widely applied in the field of energy conversion and storage, due to their high specific surface area, low cost, high conductivity, tunable chemical modification (e.g., heteroatom doping), and variable morphological features (e.g., 1D, 2D, and 3D morphologies) [ 99 , 100 , 101 , 102 ]. As is well known, the poor conductivity of LDH greatly restricts the electron transfer between the bulk catalysts and reactant species, thus leading to the high overpotential of reactions [ 103 ].…”

Recent Advances of Modified Ni (Co, Fe)-based LDH 2D Materials for Water Splitting

“…As one of the huge reserve resources, carbon-based materials have been widely applied in field of energy conversion and storage, due to their high specific surface area, low cost, high conductivity, tunable chemical modification (e.g., heteroatom doping) and variable morphological features (e.g., 1D, 2D and 3D morphologies) [99][100][101][102]. As well known, the poor conductivity of LDH greatly restricts the electron transfer between the bulk catalysts and reactant species, thus leading to high overpotential of reactions [103].…”