Coal Char Derived Few-Layer Graphene Anodes for Lithium Ion Batteries

Abstract

Few-layer graphene films were synthesized through chemical vapor deposition technique using coal char as solid carbon source. Raman spectroscopy, X-ray diffraction, transmission electron microscopy, and selected area electron diffraction were used to characterize the graphene films. The electrochemical performance of the coal char derived few layer graphene anodes for lithium ion batteries was investigated by charge/discharge curves and discharge capacity at different current densities. The graphene anode maintained the reversible capacity at ~0.025, 0.013, and 0.007 mAh/cm 2 at a current density of 10, 30, and 50 µA/cm 2 , respectively. The coal char derived graphene anodes show potential applications in thin film batteries for nanoelectronics.

Nanodiamonds Produced from Low-Grade Indian Coals

“…However, the productions of nanodiamonds with purity, size selectivity, deaggregation, surface functionality, and photoluminescence have remained a challenging task . The coal is being considered as an abundantly available cheap feedstock for the fabrication of carbon nanomaterials and several researchers reported the same, including for the production of carbon nanotubes, − microballs, carbon nanodots, − onion-like fullerenes, − and graphene/graphene oxide. − In some of the previous studies, the formation of carbon nanotubes, nanoballs, onion-like fullerenes, and chemically converted graphene-like carbon nanosheets from Northeast Indian low-grade coal has been reported …”

Synthesis of graphene: Potential carbon precursors and approaches

“…Several other attempts were made to synthesize graphene from bituminous coal [55] and lignite coal [205]. Wang et al [206] successfully synthesized graphene from bituminous coal by first electrolyzing the coal to obtain its by-product, coal char, and then a CVD process to form graphene film. Through this process, complete graphene films with large areas were produced.…”

One-step generation of S and N co-doped reduced graphene oxide for high-efficiency adsorption towards methylene blue

“…The D band could be caused by defects in the graphene sheets and the G band could be attributed to the tangential vibrations of sp 2 bonded carbon atoms. 33 The I D /I G value of S-N-rGO was calculated to be 1.21, which was much higher than that of rGO (0.98) and GO (0.92) due to the introduction of S and N. FTIR spectroscopy was employed to characterize the carbon species in S-N-rGO and GO. As shown in Fig.…”