Confine Sulfur in Polyaniline-Decorated Hollow Carbon Nanofiber Hybrid Nanostructure for Lithium–Sulfur Batteries

Abstract

A polyaniline-decorated hollow carbon nanofiber (HCNF@PANI) hybrid nanostructure was prepared as a conductive matrix for effective trapping of sulfur and polysulfides as a cathode material for Li−S batteries. The synthesized composites were characterized and examined by X-ray diffraction, Fourier transformation infrared spectroscopy, nitrogen adsorption−desorption measurements, field emission scanning electron microscopy, scanning transmission electron microscopy, and electrochemical methods, such as cyclic voltammetry, galvanostatic charge−discharge tests, and rate performance tests. The obtained HCNF@PANI-S composite showed an obvious core−shell structure with a PANI layer coating on the surface of the HCNF, and sulfur homogeneously distributes in the coating layer. The HCNF@PANI-S composite exhibited much better electrochemical performance than the HCNF-S composite, which delivered initial discharge capacity of 960 mAh g −1 and maintained 535 mAh g −1 after 200 cycles at 0.5 C rate. The improvements of electrochemical performances may be attributed to the unique hybrid nanostructure of HCNF@PANI and good dispersion of sulfur in the HCNF

Review on Li‐Sulfur Battery Systems: an Integral Perspective

“…[98][99][100][101] Surface coating of sulfur with conductive polymers [ 38,89,[102][103][104][105][106][107][108] and oxides [ 19,109 ] forms core-shell structures which enable polysulfi de confi nement and adaptation to volume changes (Figure 6 c). These composite sulfur electrodes exhibit a novel electrochemical behavior with a single output plateau at about 1.9 V without the typical plateau around 2.3 V (vs. Li + /Li), which is ascribed to the reduction from cyclo-S 8 molecule to the electrolyte-soluble Lipolysulfi des.…”

Mesoporous TiO2 Nanofiber as Highly Efficient Sulfur Host for Advanced Lithium–Sulfur Batteries

“…The nitrogen adsorption and desorption isotherms of the TiO 2 and TiO 2 /S composite were obtained, which correspond to type IV isotherms in the IUPAC classification with a typical mesopore hysteresis loop, from Figure 5(a) [22,23]. Notably, compared with TiO 2 /S composite, TiO 2 has larger pore volume and specific surface area.…”

Lithium-Sulfur Battery

“…The functional groups and unique chain structure of conducting polymers further effectively confine sulfur species within the cathode [73,74]. Many conducting polymers have been sulfur cathodes, including polyaniline (PANI) [29,[75][76][77] and polypyrrole (PPy) [78,79]. For example, Zhang et al synthesized PPy nanowire through a surfactant mediated approach, and further prepared sulfur-PPy composites by heating the mixture of element sulfur and PPy nanowire together [79].…”