Converting CO2into an Oxygenated Alkynyl Carbon Material with High Electrochemical Performance through a Mechanochemical Reaction with CaC2

Abstract

Developing new uses of CO2 and renewable energy technology is crucial for CO2 mitigation, which can be realized simultaneously through the synthesis of advanced functional carbon materials using CO2 as a carbon source. Herein, an oxygenated alkynyl carbon material (OACM) was synthesized via the solvent-free mechanochemical reaction of CaC2 and CO2 under mild conditions, and its electrochemical performance as a supercapacitor electrode was investigated. The gas-solid reaction here is efficient and cost effective owing to the mechanical activation of CaC2. The resultant nanosized OACM features a 3D structure with alkynyl-linked oxygenated carbon chains, hierarchical porosity, numerous defects, high oxygen content, and polycrystalline state. The OACM exhibits high electrochemical performance, including a high specific capacitance (121.8 F g-1 under 0.15 A g-1), superior electrical conductivity (1522 S m-1), and excellent cycling stability (above 96.6% in 5000 cycles) due to its unique structure. This work provides a new CO2 use and an innovative synthesis approach for high-performance alkynyl carbon materials.