SnO₂@TiO₂ heterojunction nanostructures for lithium-ion batteries and self-powered UV photodetectors with improved performances

To overcome the issue of inferior cycling stability and rate capacity for SnO₂ anode materials in lithium-ion batteries, an effective strategy is explored to prepare a hybrid material consisting of rutile SnO₂ nanoparticles and rutile TiO₂ nanorods, considering not only the small lattice mismatch to achieve a better composited lattice structure but also their superior synergistic effect in electrochemical performances. The as-prepared SnO₂@TiO₂ material, directly formed on a carbon cloth as a binder-free anode, exhibits a reversible capacity of 700 mAhg^-1 after 100 discharge/charge cycles at 200 mAg^-1, as well as excellent cycling stability and rate capacity. After being calcinated at high temperature, the produced hollow SnO₂@TiO₂ hybrid microtubes were directly used to fabricate photoelectrochemical (PEC) UV detectors for future devices with self-powered function. A high photocurrent response of 0.1 mAcm^-2 was observed, together with an excellent selfpowered and fast response and "visible blind" characteristics. Such a hybrid material could achieve a complementary effect in lithium-ion batteries and a superior band gap match in photovoltaic devices, and could consequently be extended to applications such as dye-sensitized solar cells and supercapacitors.