In this paper, AlO/Ag/AlO sandwiched thin films were deposited by magnetron sputtering. AlO thin films with embedded Ag nanoparticles (AgNPs) have been fabricated by adopting appropriate experimental parameters. The measurements on the resistive switching behaviors demonstrated that the embedded AgNPs could substantially enhance the local electric field, and effectively reduce the switching voltages, resulting in a sharply increased OFF/ON ratio up to 10 at 0.5 V. Furthermore, the cycling stability was considerably improved owing to the reduced randomness for the formation and rupture of conductive filaments (CFs). AgNPs could also contribute with movable Ag ions, and the Ti top electrode usually reacts with AlO promoting the formation of oxygen vacancies. As a result, a hybrid CF with better high-temperature stability was induced. Comparatively, if the embedded Ag sublayer is smooth, the switching parameters become dispersive owing to the random formation and rupture of CFs, and the switching performance is deteriorated. A physical model was proposed to understand the effect of the embedded AgNPs.

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Development of high-power lithium-ion batteries with high safety and durability has become a key challenge for practical applications of large-scale energy storage devices. Accordingly, we report here on a promising strategy to synthesize a high-rate and long-life Li4Ti5O12-TiO2 anode material. The novel material exhibits remarkable rate capability and long-term cycle stability. The specific capacities at 20 and 30 C (1 C = 175 mA g−1) reach 170.3 and 168.2 mA h g−1, respectively. Moreover, a capacity of up to 161.3 mA h g−1 is retained after 1000 cycles at 20 C, and the capacity retention ratio reaches up to 94.2%. The extraordinary rate performance of the Li4Ti5O12-TiO2 composite is attributed to the existence of oxygen vacancies and grain boundaries, significantly enhancing electrical conductivity and lithium insertion/extraction kinetics. Meanwhile, the pseudocapacitive effect is induced owing to the presence of abundant interfaces in the composite, which is beneficial to enhancing specific capacity and rate capability. Additionally, the ultrahigh capacity at low rates, greater than the theoretical value of spinel Li4Ti5O12, may be correlated to the lithium vacancies in 8a sites, increasing the extra docking sites of lithium ions.