Despite outstanding theoretical energy density (2600 Wh kg–1) and low cost of lithium–sulfur (Li–S) batteries, their practical application is seriously hindered by inferior cycle performance and low Coulombic efficiency due to the “shuttle effect” of lithium polysulfides (LiPSs). Herein, we proposed a strategy that combines TiO–TiO2 heterostructure materials (H-TiO x , x = 1, 2) and conductive polypyrrole (PPy) to form a multifunctional sulfur host. Initially, the TiO–TiO2 heterostructure can enhance the redox reaction kinetics of sulfur species and improve the conductivity of sulfur cathode together with the PPy coating layer. Moreover, the defect-abundant H-TiO x matrices can trap LiPSs by the formation of Ti–S bond via the Lewis acid–base interaction. Furthermore, the PPy coating can physically hinder the diffusion of LiPSs, as well as chemically adsorb LiPSs by the polar–polar mechanism. Benefiting from the synergistic effect of H-TiO x and PPy layer, the novel cathode delivered high specific capacities at different current rates (1130, 990, 932, 862, and 726 mAh g–1 at 0.1, 0.2, 0.3, 0.5, and 1C, respectively) and an ultralow capacity decay of 0.0406% per cycle after 1000 cycles at 1C. This work can not only indicate effectiveness of employing H-TiO x materials to realize the LiPSs immobilization but also shed light on the feasibility of combining different materials to achieve the multifunctional sulfur hosts for advanced Li–S batteries.

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Carbonaceous anode materials are commonly utilized in the energy storage systems, while their unsatisfied electrochemical performances hardly meet the increasing requirements for advanced anode materials. Here, activated amorphous carbon (AAC) is synthesized by carbonizing renewable camellia pollen grains with naturally hierarchical structure, which not only maintains abundant micro- and mesopores with surprising specific surface area (660 m2 g−1), but also enlarges the interlayer spacing from 0.352 to 0.4 nm, effectively facilitating ions transport, intercalation, and adsorption. Benefiting from such unique characteristic, AAC exhibits 691.7 mAh g−1 after 1200 cycles at 2 A g−1, and achieves 459.7, 335.4, 288.7, 251.7, and 213.5 mAh g−1 at 0.1, 0.5, 1, 2, 5 A g−1 in rate response for lithium-ion batteries (LIBs). Additionally, reversible capacities of 324.8, 321.6, 312.1, 298.9, 282.3, 272.4 mAh g−1 at various rates of 0.1, 0.2, 0.5, 1, 2, 5 A g−1 are preserved for sodium-ion batteries (SIBs). The results reveal that the AAC anode derived from camellia pollen grains can display excellent cyclic life and superior rate performances, endowing the infinite potential to extend its applications in LIBs and SIBs.