| Lithium ion batteris (LIBs) is a new generation green non-pollution battery, and it has been widely accepted since 1990s. Nowdays, it has found applications in portable electron apparatus, electric vehicles and aviation fields for its many obvious advantages, such as high voltage, large specific capacity, long cycle life, no memory effect, pollution-free to environment and so on.The anode materials for LIBs are the key to its whole performance. Among many kinds of anode materials for lithium-ion batteries, graphite carbons have been commercialized owing to its excellent cycling behavior upon repeated charge and discharge cycles. However, the graphite anode has some disadvantages including electrical disconnection, structural deformation, initial loss of capacity, and limitation of theoretical capacity of 372 mAh·g-1. The anode materials commercialized have reached their ultimate properties. What's more, these disadvantages of carbon materials induce the development of new material technology becoming an urgent task for the lithium ion batteries. So seeking new anode materials with high charge capacities and excellent cyclabilities, has become a hotspot in the research of LIBs.In the past few years, Sn-based binary and ternary oxides with various morphologies have become attractive anode materials for LIBs due to their feasible low potentials for Li+ insertion and high reversible storage capacities. The Sn-based binary oxides such as SnO2, SnO2/C, SnO2/Al2O3 have been widely studied. In addition, the Sn-based ternary oxides, especially, a number of stannates, ASnO3 (A = Ca, Sr, and Ba) and M2SnO4 (M = Mg, Mn, Co, Zn) have been investigated as anode materials for LIBs. Among these anode materials, CaSnO3 is paid more attention because of its advantages such as high theoretical specific capacity (570 mAh·g-1), low-voltage, low cost, no toxicity.It is known that the electrochemical performance of electrode materials is closely related to their microstructures and morphologies. An effective method to improve the electrochemical performance of LIBs is to increase the contact area between the active materials and electrolyte, making Li+ insertion/extraction more sufficiently. For this purpose, keeping more porosity of the active materials through assembling them into three-dimensional architecture seems to be an effective way. The hydrothermal method is a facile way to prepare electrode materials, through which peculiar morphologies can be obtained.In this work, porous flowerlike CaSnO3 by a hydrothermal route and heat treatment was synthesized successfully. The electrochemical properties were investigated by galvanostatic cycling and cyclic voltammetry. The main work in this thesis is as follows:1. Flowerlike CaSn(OH)6 precursors were synthesized via a hydrothermal route and then converted the precursors into flowerlike CaSnO3 with similar morphologies by heat treatment. X-ray diffraction spectroscopy (XRD), Raman spectroscopy, Scanning electron microscopy (SEM) and BET method are used to characterize the physical properties of samples.2. The electrochemical performance of flowerlike CaSnO3 was studied. The experimental results showed that flowerlike CaSnO3 exhibited a high capacity, excellent cycling performance and excellent rate performance. The capacity increases and rate performance gets better as the calcination temperature increases.3. Hollow cube C-doped CaSnO3 was obtained after CaSnO3 prepared at 1000 oC was treated hydrothermal route and heat treatment. The physical properties and electrochemical performance of hollow cube C-doped CaSnO3 were studied. The electrochemical experimental results showed that hollow cube C-doped CaSnO3 exhibited more excellent rate performance and higher efficiency than flowerlike CaSnO3.
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