HTiNbO5 has been widely investigated in many fields because of its distinctive properties such as good redox activity, high photocatalytic activity, and environmental benignancy. Here, this work reports the synthesis of one-dimensional H0.92K0.08TiNbO5 nanowires via simple electrospinning followed by an ion-exchange reaction. The H0.92K0.08TiNbO5 nanowires consist of many small "lumps" with a uniform diameter distribution of around 150 nm. Used as an anode for lithium-ion batteries, H0.92K0.08TiNbO5 nanowires exhibit high capacity, fast electrochemical kinetics, and high performance of lithium-ion uptake. A capacity of 144.1 mA h g-1 can be carried by H0.92K0.08TiNbO5 nanowires at 0.5 C in the initial charge, and even after 150 cycles, the reversible capacity can remain at 123.7 mA h g-1 with an excellent capacity retention of 85.84%. For H0.92K0.08TiNbO5 nanowires, the diffusion coefficient of lithium ions is 1.97 × 10-11 cm2 s-1, which promotes the lithium-ion uptake effectively. The outstanding electrochemical performance is ascribed to its morphology and the formation of a stable phase during cycling. In addition, the in situ X-ray diffraction and ex situ transmission electron microscopy techniques are applied to reveal its lithium storage mechanism, which proves the structure stability and electrochemical reversibility, thus achieving high-performance lithium-ion uptake. All these advantages demonstrate that H0.92K0.08TiNbO5 nanowires can be a possible alternative anode material for rechargeable batteries.
Keywords: electrospinning; hydrogen potassium titanium niobate; in situ X-ray diffraction; lithium-ion batteries; nanowires.