Carbon nanosheets composited with MgO/CaO prepared by one-step co-pyrolysis strategy for efficient H2S oxidation at room temperature

Abstract

Carbon nanosheets have promising application in desulfurization but are challenged by high cost and cumbersome preparation process. In this work, carbon nanosheets composited with CaO and MgO (MgxCay/C) were fabricated by one-step co-pyrolysis of magnesium gluconate and calcium gluconate. This carbon nanosheets material enables the efficient room temperature H2S oxidation in a moist atmosphere. The characterization results indicate that this co-pyrolysis strategy produces defect-rich carbon nanosheets with uniformly distributed oxides nanoparticles for the adsorption and activation of H2S as well as O2. Significantly, numerous nanoholes with a size of 5–20 nm are obtained on the carbon nanosheets, which serve as S storage space to form S polymer resistant to further oxidation, inhibiting the formation of H2SO4 and its subsequent consumption of active components. As a result, the Mg1Ca9/C shows a tremendous H2S capacity of 858.5 mg/gcat.. In addition, the processes of H2S oxidation over the MgxCay/C and its deactivation are also detailly illustrated. This study contributes to providing a low-cost and facile preparation approach for carbon nanosheets in desulfurization and other diverse applications.