Solvent‐Free Mechanochemical Synthesis of Nitrogen‐Doped Nanoporous Carbon for Electrochemical Energy Storage

Abstract

Nitrogen-doped nanoporous carbons were synthesized by a solvent-free mechanochemically induced one-pot synthesis. This facile approach involves the mechanochemical treatment and carbonization of three solid materials: potassium carbonate, urea, and lignin, which is a waste product from pulp industry. The resulting nitrogen-doped porous carbons offer a very high specific surface area up to 3000 m g and large pore volume up to 2 cm g . The mechanochemical reaction and the impact of activation and functionalization are investigated by nitrogen and water physisorption and high-resolution X-ray photoelectron spectroscopy (XPS). Our N-doped carbons are highly suitable for electrochemical energy storage as supercapacitor electrodes, showing high specific capacitances in aqueous 1 m Li SO electrolyte (177 F g ), organic 1 m tetraethylammonium tetrafluoroborate in acetonitrile (147 F g ), and an ionic liquid (1-ethyl-3-methylimidazolium tetrafluoroborate; 192 F g ). This new mechanochemical pathway synergistically combines attractive energy-storage ratings with a scalable, time-efficient, cost-effective, and environmentally favorable synthesis.

Nitrogen‐Doped Biomass‐Derived Carbon Formed by Mechanochemical Synthesis for Lithium–Sulfur Batteries

“…In a previous study, we developed a mechanochemical synthesis concept based on commercially available Kraft lignin, urea, and potassium carbonate to synthesize nitrogen‐doped porous carbons and showcased their applicability as supercapacitor electrode materials. Herein, we present a follow‐up in which we use various sustainable and renewable precursors, while applying a mechanochemical solvent‐free one‐pot synthesis (Scheme ).…”

“…The nitrogen source is varied to increase the nitrogen content and to broaden the functionalities. Finally, we have extended the applicability of the developed N‐doped carbons from supercapacitor electrodes to lithium–sulfur batteries. Thereby, the discussed carbons show a superior performance as cathode materials compared with non‐doped carbons and the often employed carbon black material.…”

Mechanochemical Functionalization of Carbon Black at Room Temperature

“…The application of carbon materials is enormously widespread, ranging from catalysis [1], sorption, and separation [2,3], to energy storage in batteries [4], supercapacitors [5], and fuel cells [6]. The requirements carbons have to meet are strongly dependent on their applications.…”

Sustainable Salt Template‐Assisted Chemical Activation for the Production of Porous Carbons with Enhanced Power Handling Ability in Supercapacitors

“…[22,52,53] However, the rate capability in this less conductive electrolyte was lower for all the materials tested, as can be seen in Figure 7b. [22,[54][55][56][57] Nevertheless, the higher cell voltage of Li 2 SO 4 -based supercapacitors leads to an increase in the amount of energy stored of ca. This is further supported by EIS (Figure 8c), which not only reveals a higher ESR in the neutral electrolyte compared to the acid one, but also a much greater resistance to the diffusion of ions.…”