Nitrogen-doped Carbon with Modulated Surface Chemistry and Porous Structure by a Stepwise Biomass Activation Process towards Enhanced Electrochemical Lithium-Ion Storage

Abstract

Controllable conversion of biomass to value-added carbon materials is attractive towards a wide variety of potential applications. Herein, hydrothermal treatment and KOH activation are successively employed to treat the cheap and abundant camellia oleifera shell as a new carbon raw material. It is shown that this stepwise activation process allows the production of porous nitrogen-doped carbon with optimized surface chemistry and porous structure compared to the counterparts prepared by a single activation procedure. Benefiting from the modulated porous structure, the as-produced porous nitrogen-doped carbon electrode delivered a high reversible capacity of 1080 mAh g−1 at a current density of 100 mA g−1, which is 3.3 and 5.8 times as high as that of the carbon materials prepared by bare hydrothermal treatment or KOH activation, respectively. Moreover, the optimized surface composition of the porous nitrogen-doped carbon endows it with a highest initial Coulombic efficiency among the three samples, showing great potentials for practical applications. This work is expected to pave a new avenue to upgrade biomass to carbon materials with tunable surface properties and microstructures for target applications.

Fabrication and lithium storage performances of a composite of tin disulfide and ordered mesoporous carbon

“…According to the deconvoluted N 1s XPS in figure 4e, there were three bonding types between N and C. In particular, the peaks at 399.1 eV and 400.6 eV are associated to pyridinic N and pyrrolic/pyridonic N bonds, respectively (figure 4f). [20] According to the previous reports, [21][22] doping N heteroatoms into C networks would increase the number of active sites for lithium storage as well as the electrical conductivity for the carbonaceous materials. Hence, the doping N was expected to benefit for the electrochemical performances of the synthesized CMK-3/SnS 2 composite.…”

Sono‐exfoliated graphene‐like activated carbon from hazelnut shells for flexible supercapacitors

“…The Raman spectra of Exf.ACHS (1:3, 900, 2) and ACHS (1:3, 900, 2) samples are shown in Figure 2B and those for the rest of chemically activated ACHS samples, sono‐exfoliated ACHS samples are shown in Figure S1C,D, respectively (Supporting information). All the spectra consist of two prominent peaks at 1336 and 1567 cm −1 which are ascribed to the D and G bands respectively 39,57 . The D‐band corresponds to the in‐plane vibrations of disordered sp 2 carbon atoms whereas the G‐band arises from the in‐plane vibrations of sp 2 bonded graphitic carbon structures 57 .…”

“…39,57 The Dband corresponds to the in-plane vibrations of disordered sp 2 carbon atoms whereas the G-band arises from the inplane vibrations of sp 2 bonded graphitic carbon structures. 57 The D and G bands of these biomass derived activated carbon samples are shifted to lower wavenumbers when compared to traditional graphene 58 (D band: $1350 cm À1 and G band: $1590 cm À1 ) which may be due to external factors such as differences in the preparation conditions, mechanical compression and thermal expansion etc. 59 The position of the G-band is particularly sensitive to the number of layers present in a graphene sample.…”

Applications of Chinese Camellia oleifera and its By-Products: A Review

“…It shows high selective adsorption and is widely used in decolorization and water purification. Camellia shell activated carbon has more functions compared with the conventional activated carbon, and Camellia shell activated carbon products with different adsorption characteristics can be prepared using various methods ( Sun et al, 2011 ; Guo et al, 2016 , 2018 ; Fan et al, 2017 ; Nie et al, 2019 ). C. oleifera shell can be used to synthesize zirconium dioxide biochar and improve the removal of fluorine in water ( Lei et al, 2019 ).…”