Electrochemical Synthesis and Structural Characteristics of New Carbon-Based Materials Generated in Molten Salts

Abstract

This article is devoted to providing a new feasible route to realize carbon dioxide reduction and resource utilization. With the wide electrochemical window, high thermal stability and fast mass transfer rate of molten salt electrolyte, new carbon-based materials can be synthesized on the surface of the inexpensive Fe cathode. EDS (Electron-Dispersive-Spectroscope), SEM (Scanning-Electron-Microscope) and BET (Brunauer-Emmett-Teller) analyzers are selected to detect the critical element, microstructures and specific surface area of the new carbon-based materials generated via electrolysis. It is demonstrated that eutectic carbonates’ electrochemical reduction, ranging from 450 °C to 750 °C prefers to produce carbons with no high-value structure. While carbon products are observed with honeycomb-like and platelet structures at 450 °C with an increase in current density. Additionally, the feedstock CO2 could be converted into carbon-based materials with high value such as high surface area carbon, spherical carbon and cellular porous carbon production by optimizing the electrolysis parameters of temperature, current density and molten salt conformation. This paper shows a viable way for one-pot CO2 utilization and facile production of micro-scale structure carbon materials, in line with the concept of sustainable development.

Pulsed Current for Diameter-Controlled Carbon Nanotubes and Hybrid Carbon Nanostructures in Electrolysis of Captured Carbon Dioxide

“…In addition to MWCNT synthesis, many different nanostructured carbons have been synthesized through the electrolysis of CO 2 in molten carbonates, including porous carbons, , graphene-based materials, carbon onions, and others. − Unlike MWCNT growth, these are most commonly noncatalytic processes governed by classical nucleation principles during the electrodeposition of carbon on surfaces. In comparison to conventional MWCNT growth, where hydrocarbon precursors crack into some percentage of active gas species, such as vinyl acetylene, , which can then decompose on the surface of the catalyst, the carbon flux in electrocatalytic growth is controlled by the current density and not the reaction on the catalyst particle surface.…”

“…Therefore, the understanding and control of catalyst reduction, which has been deemed as critical toward the resulting diameter of the MWCNT in gas-phase MWCNT synthesis methods, remains unexplored for electrocatalytic MWCNT synthesis. 13,34 In addition to MWCNT synthesis, many different nanostructured carbons have been synthesized through the electrolysis of CO 2 in molten carbonates, including porous carbons, 35,36 graphene-based materials, 37 carbon onions, 38 and others. 39−41 Unlike MWCNT growth, these are most commonly noncatalytic processes governed by classical nucleation principles during the electrodeposition of carbon on surfaces.…”

Melting Behavior and Densities of K2B2OF6 Melts Containing KReO4

“…It is widely known that, by using molten salts, it is possible to obtain metallic coatings with desired properties, including roughness, mechanical strength, specific surface, density, etc. [19,20].…”