Graphene oxide-doped stearate-intercalated layered double oxide nanocomposites as high-performance CO2 adsorbents

Abstract

The nanocomposites of graphene oxide (GO)-doped stearate-intercalated layered double oxides (LDO) as a new type of CO2 adsorbents at medium temperatures (200–400 °C) are reported for the first time. The doping of GO could improve stability of the composite material. The CO2 adsorption uptake (0.52 mmol/g) of LDO-Stearate (LDO-SA) was significantly increased by intercalating the long carbon chain organic anion of stearate. The 6 wt% GO − LDO-SA (6GO − LDO-SA) nanocomposite possessed the largest CO2 adsorption uptake (0.83 mmol/g), which was much larger than that (0.35 mmol/g) of the conventional LDO adsorbent. Such a high performance of 6GO − LDO-SA was associated with its increase in surface area and basic site amount. The adsorption process of CO2 on the nanocomposite was dominated by the chemical adsorption, and the adsorbed CO2 was mainly stored in the form of carbonate. The regeneration efficiency of 6GO − LDO-SA was>88% after 10 adsorption and desorption recycling tests, which was much higher than that of LDO. Simultaneously, the 6GO − LDO-SA adsorbent exhibited a fast kinetics (0.863 mmol/(g·min)) under the medium-temperature conditions. We are sure that the new nanocomposite materials fabricated in the present study are promising in the applications of carbon dioxide capture.