CO2-Rich Gas Conversion to Carbon Nanotube via Molten Salt Electrolysis

Abstract

Abstract The CO2 capture via electrolysis process is a potentially promising and attractive pathway for greenhouse gas removal and global warming reduction by converting CO2 into value-added materials. In this study, the conversion of CO2 from CO2-rich gas into value-added carbon nanomaterial was successfully achieved via molten Li2CO3 electrolysis with a NiCr anode and a stainless steel cathode. The characterization by FESEM and TEM analyses showed that the obtained carbon product was a carbon nanotube with a bamboo-like structure and an outer average diameter of 36 nm. The EDS and XRD characterization indicated the growth of carbon nanotube in electrolysis was achieved through metal nucleation points on the electrolysis cathode. In addition, the Raman analysis showed that the carbon product exhibited high quality and crystallinity. The results from the present study revealed that the molten carbonate electrolysis offered a viable approach for direct transformation of CO2 from industrial flue gas into valuable carbon product, providing an alternative solution to reduce CO2 emissions.