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[Display omitted] • An all-solid-state (ASS) strategy without using any solvents and activators was developed. • The ASS strategy derived carbon owns abundant nitrogen species and large packing density. • The resultant product show superior supercapacitor performances with both high gravimetric and volumetric performances. Template synthesis of porous carbon with rich functionalities by a scalable strategy without using any solvents and activators will be a green and promising route. Herein, we reported an all-solid-state synthesis strategy by mixing glucose and graphitic carbon nitride (g -C 3 N 4) by milling and then undergoing a segmented carbonization in which first at low temperature of 573 K to polymerize sucrose onto g -C 3 N 4 , then at high temperature of 973 K to carbonized the composite to obtain a porous carbon (denoted as GNC) with abundant nitrogen species over 20 atom% and large packing density (0.91–1.25 g cm−3). Due to the features of large packing density and rich electrochemically-active N species, as electrode for supercapacitive energy storage, the developed GNC exhibit a comparable energy storage level with both high gravimetric energy density of 26.8 Wh kg−1@1000 W kg−1 and volumetric energy density of 30.8 Wh L−1@1150 W L−1, suggesting a potentiality in energy storage field. Importantly, the present strategy owns characteristics of ease of operation, green and scalable, which would be a promising synthesis route towards the fabrication of functional carbon utilizing in many fields like sorption & separation, catalysis, energy storage and so on. [ABSTRACT FROM AUTHOR]

[Display omitted] • A solvent-freely polymerizing catechol and paraformaldehyde method was developed. • The present method derived carbon owns high nitrogen functionalties of 21.7 atom%. • The derived carbon achieves high energy density of 34.5 Wh L−1@1370 W/L. Fabrication of nitrogen functionalized carbon with high nitrogen content (over 10 atom%) by a route with simplified and solvent-free procedures would be both economically and environmentally scalable. We demonstrate here a simple solvent-free route towards synthesizing porous carbon doped by nitrogen functionalties (21.7 atom%) involving solid state catalytic polymerization of catechol and paraformaldehyde with g -C 3 N 4 as catalyst. Upon high-temperature treatment, the vaporized catechol and paraformaldehyde would be in situ polymerized on the surface of g -C 3 N 4 forming the composite of g -C 3 N 4 @resin. During the following carbonization process, the resin was carbonized to carbon skeleton, while the g -C 3 N 4 would be decomposed in situ doping the carbon skeleton. In our design, the avoidance of solvents in the whole synthesis procedure and the usage of g -C 3 N 4 in the preparation not only reduces the waste production, but also introduces high nitrogen species (21.7 atom%). As electrode for supercapacitor, the resultant SFC based electrode achieves a large specific capacitance of 391F cm−3@1.0 A/g and high energy density of 34.5 Wh/L@1370 W/L, suggesting a potential as electrode for energy storage. And more, the developed method offers a promising and alternative route for the fabrication of new materials in manner of green and environmentally friendly. [ABSTRACT FROM AUTHOR]

As an industrial material for supercapacitive energy storage, commercial activated carbons (AC) could achieve a satisfactory gravimetric performances by electric double layered capacitance (EDLC) due to their rich microporosity, but the volumetric performances are usually poor resulted from the low packing density. Herein, we presented a strategy to address this tradeoff relationship and to achieve both high gravimetric and volumetric performance by filling the macro/mesoporosity with extra nitrogen doped carbon. The reconstructed activated carbon could inherit most of microporosity from the parent AC, while the macro/mesoporosity of them was greatly decreased, resulting in increase of packing density and the improvement of surface hydrophilicity. Benefited from the increase of packing density and maintenance of microporosity, the resultant activated carbon achieves greatly enhanced energy storage level including three times higher capacitance of 384 F cm−3@ 1.0 A/g (vs 128 F cm−3@ 1.0 A/g for pristine AC), high rate capability of 73.4% (vs 59.2% for pristine AC), larger energy density of 27.5 Wh L−1@ 900 W L−1 (vs 10.0 Wh L−1@747 W L−1). Importantly, the present strategy provides a facile and unique method to process activated carbon, which offers a possibility improving the energy storage level of the commercial activated carbon. [Display omitted] • Commercial activated carbon (AC) was processed by filling the macro/mesoporosity. • The filled AC owns increased packing density and more nitrogen functionalities. • The filled AC achieves greatly enhanced supercapacitor performances. [ABSTRACT FROM AUTHOR]