Clean utilization of palm kernel shell: sustainable and naturally heteroatom-doped porous activated carbon for lithium–sulfur batteries

Abstract: Lithium–sulfur batteries (LSBs) have received much concern as emerging high-power energy storage system. Nevertheless, the low conductivity of sulfur and polysulfide shuttle results in low rate capability and rapid capacity decay, which seriously limit its commercial application. Here, facile, sustainable and cost-effective strategy for preparing heteroatom-doped porous activated carbon (PAC) derived from biomass palm kernel shell (PKS) was developed for high-performance LSB applications. The presence of N, P and S heteroatoms with modification of the surface polarity brings about large amounts of active sites and improved adsorption property compared to those of common carbon materials. The PAC sample possesses desirable specific surface area (SSA) (2760 m·g) as well as pore volume (1.6 cm·g). Besides, the good electrical conductivity of PAC endows the material with excellent rate performance. The PAC-S electrode with a 60% of sulfur loading has a desirable first discharge capacity (1045 mAh·g, 200 mA·g) with superb discharge capacity (869.8 mAh·g, 100th cycle) and cyclability (312.6 mAh·g, 800 mA·g, 1000th cycle), which can be mainly ascribed to its unique porous properties and the good conductivity of PAC. Graphic abstract: [Figure not available: see fulltext.].