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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]

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]

• This work explains that TiO 2 and ZnO can significantly modulate the resonance wavelength range of SPR sensors. • It is experimentally demonstrated that the two oxide films have the effect of enhancing the sensitivity of the SPR sensor. • The dual-channel sensor prepared using the cascade method of two oxide films has a wide sensing bandwidth. • The performance of the proposed dual-channel sensor is highly stable and not easily oxidized. In order to broaden the bandwidth of SPR dual-channel sensors, this work proposes to tune the resonance wavelength range of the sensors using a cascade of ZnO and TiO 2 films. The two oxides are transversely deposited on Ag-based no-core fiber to form a dual-channel sensor that can be used for refractive index (RI) and temperature measurements. Among them, Ag/ZnO is used for RI sensing and Ag/TiO 2 /PDMS is used for temperature sensing. The simulation and experimental results show that ZnO and TiO 2 have the effect of broadening the resonance wavelength range by 44 nm and 72 nm, respectively. In addition, when the two oxides are added to the Ag-based sensor, the SPR valley is red-shifted, and the sensitivity is enhanced. The experimental results also show that the two oxides make the silver film less susceptible to oxidation and enhance the stability of the sensor. Numerical results show that the maximum RI sensitivity of the sensor is 4630 nm/RIU, and the temperature sensitivity is 5.8 nm/°C. The range of the object to be measured is 1.333–1.385, 0–50 °C. This ability to broaden the sensor bandwidth provides a new direction for designing and applying high-performance multi-channel SPR sensors. [ABSTRACT FROM AUTHOR]

• This work utilizes TiO 2 film to tune the sensing bandwidth and the resonance wavelength range to the near-infrared band. • A dual-channel sensor with wide bandwidth is proposed. • The experimental results show that the RI range of the sensor is 1.333–1.385, and the temperature range is 10–80 ℃. • The sensor has simple structure and good repeatability. Facing the diversity and complexity of the types of parameters to be measured, multi-channel surface plasmon resonance (SPR) fiber sensors provide an excellent solution. However, the sensing bandwidth is a key factor affecting the sensor performance. In this paper, we explore a method to modulate the sensing bandwidth using the TiO 2 film. A dual-channel SPR sensor with a wide sensing bandwidth is proposed. In this sensor, no-core fiber (NCF) is used as the sensing probe, and multimode fibers are used for the transmission of optical signals. The sensor has a cascaded composite film structure, the region coated with Ag film as the refractive index sensing region and the region coated with Ag/TiO 2 /PDMS as the temperature sensing region. The experimental results show that the sensing bandwidth of the sensor varies for different TiO 2 coating times. It indicates that the TiO 2 film can regulate the sensing bandwidth flexibly. Therefore, to achieve the optimal sensing effect, the TiO 2 coating time can be flexibly adjusted according to the RI characteristics of the environment. The maximum sensitivity of this dual-channel sensor is 4.5 nm/°C and 3151 nm/RU when the temperature range is between 10 and 80 °C and the RI range is between 1.333 and 1.385, respectively. In addition, we discuss the repeatability and stability of this dual-channel sensor. [ABSTRACT FROM AUTHOR]