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Biomass-derived carbon (BDCs) materials are receiving extensive attention as electrode materials for energy storage because of the considerable economic value offering possibility for practical applications, but the electrochemical capacitance of BDCs are usually relatively low resulted from limited electric double layer capacitance. Herein, an oxygen-rich porous carbon (KMAC) was fabricated through a rapid and convenient microwave assisted carbonization and KOH activation of camellia oleifera shell. The obtained KMAC possesses three-dimensional porous architecture, large surface area (1229 m 2 /g) and rich oxygen functionalities (C/O ratio of 1.66). As the electrode materials for supercapacitor, KMAC exhibits superior supercapacitive performances as compared to the activated carbon (KAC) derived from direct carbonization/KOH activation method in 2.0 M H 2 SO 4 (315 F/g vs. 202 F/g) and 6.0 M KOH (251 F/g vs. 214 F/g) electrolyte due to the rich oxygen-containing functional groups on the surface of porous carbon resulted from the developed microwave-assisted carbonization/activation approach. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tix+ in-situ intercalation strategy via titanium foil/vanadium ion solution interface for long cycle LSB. • Inserted Tix+ can strengthen interlayer interaction so as to enhance lithium-ion mobility rate. • Mixed valence of V5+/V4+ reduces the stress and strain of lithium-ion intercalation. • Ti-VO 2.375 /S cathode delivers lower capacity decay with a stable coulombic efficiency. Lithium sulfur battery (LSB) has great potential as a promising next-generation energy storage system owing to ultra-high theoretical specific capacity and energy density. However, the polysulfide shuttle effect and slow redox kinetics are recognized the most stumbling blocks on the way of commercializing LSB. On this account, for the first time, we use Tix+ in-situ intercalation strategy via titanium foil/vanadium ion (V5+) solution interface to modify the layer of vanadium oxide for long cycle LSB. The inserted Tix+ strengthens interlayer interaction and enhances lithium-ion mobility rate. Meanwhile, based on density functional theory (DFT) calculation, the mixed valence of V5+/V4+ in the vanadium oxide structure reduces the stress and strain of lithium-ion intercalation through the interlayer support of titanium ions (Tix+). Also, Tix+ refines the structural stability of the sulfur wrapped composite matrix so as to facilitate the LiPSs transformation, and improve the electrochemical performances. Consequently, the Ti-VO 2.375 /S cathode delivers a lower capacity decay of 0.037 % per cycle over 1500 cycles with a stable coulombic efficiency around 100 %. [ABSTRACT FROM AUTHOR]