Novel 3D hierarchical bifunctional NiTiO_3 nanoflower for superior visible light photoreduction performance of CO_2 to CH_4 and high lithium storage performance

摘要

Hierarchical and uniform flower-like NiTiO3 architectures have been firstly synthesized via a facile one pot method with glycerol/ethyl alcohol-mediated route followed by an annealing treatment. The 3D NiTiO3 nanoflowers with an average size of similar to 800 nm evidenced by a field-emission-scanning electron microscope (FE-SEM) and a transmission electron microscope (TEM), were constructed by nanosheets (similar to 30 nm). The Brunauer-Emmett-Teller (BET) specific surface area analysis confirmed that properly hierarchical structures enhanced abundant mesoporous distribution and surface area. It is confirmed that properly hierarchical structures can not only increase light harvesting, but also accelerated separated efficiency of photoexcited electron-hole pairs and gave rise to a negative shift of conduction band (CB). In consequence, the photocatalytic activity of the conversion from CO2 to CH4 was obviously improved (25.8 mu mol h(-1) g(-1)) under visible light irradiation, compared with that of bulk NiTiO3. In addition, the hierarchical NiTiO3 nanoflower as anode materials for Li-ion batteries exhibited an excellent rate performance, a high specific capacity of 400 mA h g(-1) after 120 cycles, and a high coulombic efficiency of 98%, due to the large surface area, fast transport pathways provided by porous. This work, for the first time, extends the further development of NiTiO3 hierarchical architectures and introduces a simple strategy for building other ATiO(3)-based oxide hierarchical bifunctional materials. (C) 2018 Elsevier Ltd. All rights reserved.