Direct chemical conversion of co2 to versatile carbon materials and their electrochemical applications

Abstract

Carbon dioxide (CO2) is one of the major greenhouse gases that contribute to global warming and as such, much effort has been exerted to reduce the CO2 emissions into the atmosphere. Among the approaches to deal with emitted CO2 gases, CO2 conversion to useful chemicals is useful technology as removal and usage of CO2 is possible simultaneously. Herein, the versatility and the economic feasibility of the process should be pursued as considering the conversion conditions and the value of the final products. This thesis concentrated to utilize atmospheric, gaseous CO2 directly for maximizing the opportunity of industrial use. The study to convert flue gas of N2 and CO2 mixture was performed as well. In terms of the versatility, selective conversion process of CO2 contained in flue gas with the mixture of CO2 and N2 was established. This process synthesized boron and nitrogen co-doped porous carbon materials without any additional separation of flue gas. In terms of the economic feasibility, the process which produce high valuable graphene-carbon nanofiber composites instead of amorphous carbons was developed. Finally the synthesized materials from the process were studied in the terms of performance and properties as electrodcatalysts for oxygen reduction reaction and electrode materials for lithium-based secondary batteries. In other words, efficient application fields of the synthesized carbon materials were suggested considering their own characteristics.