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Summary: Bronze titanium dioxide (TiO2[B]) is widely used to improve lithium‐ion storage performances owing to their open crystal structure, pseudocapacitance effect, and high theoretical specific capacity. However, the reported storage performances of TiO2(B) for lithium‐ion batteries (LIBs) are not ideal, due to the sluggish lithium‐ion diffusivity and poor electronic conductivity. Herein, mesoporous TiO2(B) ultrathin nanosheets with rich oxygen vacancies supported on carbon nanotubes (TiO2[B]‐CNTs) were constructed to enhance lithium‐ion storages via a simple solvothermal method combined with an annealing process under Ar atmosphere. The CNTs substrate in situ induces the orderly growth of mesoporous TiO2(B) ultrathin nanosheets with ~5 nm thinness and rich oxygen vacancies into a stabilized microstructure, which not only prevent aggregation of nanosheets, but also ensure effective exposure surface, as well as enhance the electronic conductivity. As‐obtained TiO2(B)‐CNTs electrodes in LIBs at 0.1 A g−1 after 100 cycles still show superior cycling performances with ~280 mAh g−1. Specifically, the TiO2(B)‐CNTs electrodes maintain good long‐term cycling performances. The specific capacities reached ~230 mAh g−1 at 0.5 A g−1in the 700th cycle, and ~150 mAh g−1 at 2.0 A g−1 in the 1000th cycle, respectively. [ABSTRACT FROM AUTHOR]

The layered material of nickel cobalt manganese oxide lithium oxide is one of the most promising lithium-ion battery (LIBs) materials, with the characteristics of high capacity and high density. However, most nickel-rich layered oxides have the phenomenon of cation mixing and the phenomenon that the layered structure changes to the spinel structure during the cycle, which results in poor capacity and cycle performance under high cut-off voltage. Herein, we modified LiNi 0. 5 Co 0. 2 Mn 0. 3 O2 with Ti and Na co-doping to observe the changes in the specific capacity, cycle performance and crystal structure of the material. Ti and Na co-doped LiNi 0. 5 Co 0. 2 Mn 0. 3 O2 has the most obvious effect on increasing the discharge specific capacity and improving the cycle performance. In sthe voltage range of 3–4.5 V, its discharge specific capacity reaches 183.5 mAh/gat 0.5C, and the capacity retention rate after 100 cycles is 81.96%, and its discharge specific capacity reaches 164.2 mAh/g at 1C and after 100 cycles Capacity retention rate is 80.93%. The introduction of Ti and Na plays an important role in improving the cation mixing phenomenon and improving the stability of the crystal structure. The NCM523 capacity and cycling efficiency of Ti and Na co-doping pair are the best, which is attributed to the co-doping of Ti and Na, increases the Li layer spacing, stabilizes the crystal structure, and effectively prevents the collapse of crystal lamellar structure in the process of cycling. [ABSTRACT FROM AUTHOR]

Hollow spherical structures with abundant mesoporous are of great interest for electrode materials in lithium-ion batteries (LIBs). Although there are many synthetic strategies, using template-free methods to construct the hollow spherical structures still faces great challenges. Herein, we designed a simple template-free method to successfully obtain uniform hollow TiO 2 microspheres (TiO 2 –H) with a well-defined hollow interior and abundant mesoporous. Owing to the structural superiority, the as-prepared TiO 2 –H as an electrode material for LIBs delivers a high specific capacity of ∼132 mAh g−1 at a current density of 2.0 C after 200 cycles. Besides, it also exhibits satisfying long-term cycling performances with a high specific capacity of ∼100 mAh g−1 at a large current density of 5.0 C after 800 cycles. These superior cycling performances and strong structure stability of TiO 2 –H electrodes are attributed to the hollow spherical structures with large specific surface areas and rich mesoporous, which can ensure Li ion diffusion and provide sufficient electrochemical reaction sites, as well as remit the large volume changes. Image 1 • Hollow TiO 2 microspheres with abundant mesoporous were constructed by a simple and template-free method. • The unique hollow spherical structures are beneficial to accelerate lithium ion diffusion and buffer the volume expansion. • Such satisfying long-term cycling performances at large current densities for lithium storage can be obtained. [ABSTRACT FROM AUTHOR]

• Thin films based on Li-doped Zn 0.4 Ni 0.6 -δ ≏ δ O ceramic were successfully prepared. • Thin films with high Ni/Zn atom ratio still maintain the rock-salt structure. • The structure, optical, electrical properties and Li-ionic storage were investigated. • Li-doped Zn 0.4 Ni 0.6 -δ ≏ δ O films exhibit the prospect of multifunctional applications. Nanostructured (Zn 0.4 Ni 0.6 - δ ◻ δ) 0.95 Li 0.05 O thin films were successfully prepared by radio frequency magnetron sputtering. The multifunctional properties such as optical, thermal sensitivity and Li-storage of the thin films were investigated. The prepared thin films maintain a rock-salt phase, have a wide optical band gap of 3.77 eV, and show typical negative temperature coefficient (NTC) of resistivity. The thin film also delivers a high reversible specific capacity of 797 mAh g−1 after 100 cycles at 200 mA g−1 for application of an electrode in Li-ion batteries. This work provides potential functional applications in the fields of photoelectric devices, thermal sensors and new energy devices. [ABSTRACT FROM AUTHOR]