Conductive Carbon Nitride for Excellent Energy Storage

Abstract

Conductive carbon nitride, as a hypothetical carbon material demonstrating high nitrogen doping, high electrical conductivity, and high surface area, has not been fabricated. A major challenge towards its fabrication is that high conductivity requires high temperature synthesis, but the high temperature eliminates nitrogen from carbon. Different from conventional methods, a facile preparation of conductive carbon nitride from novel thermal decomposition of nickel hydrogencyanamide in a confined space is reported. New developed nickel hydrogencyanamide is a unique precursor which provides self-grown fragments of ⋅NCN⋅ or NCCN and conductive carbon (C-sp ) catalyst of Ni metal during the decomposition. The final product is a tubular structure of rich mesoporous and microporous few-layer carbon with extraordinarily high N doping level (≈15 at%) and high extent of sp carbon (≈65%) favoring a high conductivity (>2 S cm ); the ultrahigh contents of nongraphitic nitrogen, redox active pyridinic N (9 at%), and pyrrolic N (5 at%), are stabilized by forming NiN bonds. The conductive carbon nitride harvests a large capacitance of 372 F g with >90% initial capacitance after 10 000 cycles as a supercapacitor electrode, far exceeding the activated carbon electrodes that have <250 F g .

A Novel CVD Growth of g‐C3N4 Ultrathin Film on NiCo2O4 Nanoneedles/Carbon Cloth as Integrated Electrodes for Supercapacitors

“…O3 located at 532.4 eV corresponds to adsorbed water on or near the surface ,. Figure e shows three deconvoluted carbon spectra, an obvious broaden peak positions at 285 eV could be attributed to C=C and C−C coordination, while the weak peak locates at 286.8 eV relating to sp3 carbon associated with C=N bond ,. The weaker peak at the binding energy of 288.3 eV confirms the existence of sp3 carbon that associated with C−N bond in the N‐containing aromatic rings.…”

“…Furthermore, like other two‐dimensional materials such as graphene, g‐C 3 N 4 also possesses excellent mechanical strength and flexibility for those covalently bonded 2D nanomaterials can bear certain elastic deformation without breaking . Therefore, g‐C 3 N 4 is considered as a promising candidate as electrode materials for high‐rate supercapacitors . However, until now, only a few studies on the exploration of g‐C 3 N 4 as active materials for supercapacitors.…”

“…[19] Therefore, g-C 3 N 4 is considered as a promising candidate as electrode materials for highrate supercapacitors. [20] However, until now, only a few studies on the exploration of g-C 3 N 4 as active materials for supercapacitors. The existing investigations regarding g-C 3 N 4 as electrode materials for supercapacitors mainly concentrated on g-C 3 N 4 based composites.…”

One‐Step Pyrolysis to Synthesize Non‐Graphitic Nitrogen‐Doped 2D Ultrathin Carbon Nanosheets and Their Application in Supercapacitors

“…Figure d shows the total nitrogen content at different temperatures and the proportion distribution of corresponding nitrogen species. It can be seen that the total amount of nitrogen content reduced dramatically from 47.7 wt.% in NNCN‐600 to 11.0 wt.% in NNCN‐900, which was undoubtedly caused by the increase in pyrolysis temperature . While the percentage of graphitic‐nitrogen content in the total nitrogen increased dramatically from 3.15 % to 27.54 %, the non‐graphitic‐nitrogen content decreased from 46.20 wt.% to 7.97 wt.%, demonstrating that the doping level of non‐graphitic‐nitrogen was affected significantly by the temperature.…”

Graphene Quantum‐Dot‐Modified Hexagonal Tubular Carbon Nitride for Visible‐Light Photocatalytic Hydrogen Evolution

“…Semiconductor photocatalytic hydrogen evolution from water using solar energy is one potential technology [1][2][3] that has attracted more and more attentionb ys cientists owing to many rising energya nd environmental issues. Recently,g raphitic carbon nitride (g-C 3 N 4 ), an organic semiconductor photocatalyst, [4,5] has been focused on as an ovel visible-light photocatalyst for photocatalytic hydrogen evolution, [6] degradation of organic compounds, [7] and organic synthesis. [8] However,g -C 3 N 4 suffers from many disadvantages,s uch as al ow visible-light utilization efficiency,ah igh electron-hole recombination rate, and al ow surface area.…”