Soft templating synthesis of nitrogen-doped porous hydrothermal carbons and their applications in carbon dioxide and hydrogen adsorption

Abstract

Recent years, heteroatoms modified porous carbon materials have attracted particular attention due to their superior performance in adsorption, catalysis, or electrochemistry, etc. In this paper, we present a method to synthesize porous nitrogen-doped carbon materials via hydrothermal carbonization and soft templating process by using nitrogen-containing biomass derivative as precursor. The obtained materials possess relatively large Brunauer–Emmet–Teller specific surface area (up to 980 m2 g−1), pore volume, as well as high nitrogen content (6.3 wt%). The morphology, porosity, and the functionalities were investigated by using scanning and transmission electron microscope, nitrogen sorption instrument, elemental analyzer, X-ray photoelectron spectroscope, and Fourier transform infrared spectrometer, etc. The effects of soft template concentration and the pH value on the properties of the obtained materials are discussed. Furthermore, the carbon materials exhibit relatively good properties for gas adsorption: the carbon dioxide adsorption capacities (3.7–4.7 mmol g−1) and the hydrogen adsorption capacity (up to 9.0 mmol g−1).