Controllable synthesis of porous N-doped carbons using aniline and Pluronic F127 micellar system for hydrogen storage and electrochemical applications

Abstract

Despite hydrogen being an attractive energy source, there are two challenges to overcome in its use: hydrogen storage and the use of catalysts to optimize its conversion into energy. N-doped carbons are considered promising candidates for hydrogen storage and catalysis. This paper reports a fast and controllable strategy for obtaining porous N-doped carbons with a monolith-type morphology, high surface area, and hierarchical porosity. The presence of nitrogen increases the electron donor and wettability of carbons, making them favorable for use in hydrogen adsorption and electrodes. The method is based on using aniline as a carbon source and polymerizing it in a Pluronic F127 micellar system before carbonization. It is shown that the pore size and pore volume of porous carbon can be effectively tuned by using tetraethyl orthosilicate (TEOS). The relationship between aniline polymerization conditions, surface chemistry, and porous carbon properties has been investigated. Polyaniline permitted a high conversion to carbon (43.5–98.1%) and a nitrogen content of 5% wt in the N-doped carbon. In addition to the well-developed porosity and interesting monolithic morphology, electrochemical characterization showed that increasing the temperature of carbon synthesis improved the electroactive performance due to higher graphitization. In our previous study on hydrogen diffusion, we observed higher rates in our material compared to other carbon materials. This enhanced performance can be attributed to the effective combination of doping and hierarchical porosity, facilitating improved charge transfer and establishing favorable diffusion pathways. Thus, we demonstrate that pore size and surface area impact the electrochemical properties and hydrogen diffusion in this type of carbon.