Synthesis Of Micro/nano-structured Antimony Oxychloride Materials And Their Electrochemical Performance

Considering the high theoretical specific capacity,good safety and appropriate charge/discharge plateaus,Sb-based materials are regarded as promising anodes for lithium/sodium-ion batteries(LIBs/SIBs).However,synthesis of these materials mentioned above usually requires magnetron sputtering,microwave heating,high-temperature calcination,and so on,which is complicated.In this dissertation,a simple synthetic route was designed for preparing micro/nano structure antimony oxychloride and then applied in LIBs or SIBs.Furthermore,the relationships between the characteristics of antimony oxychloride and electrochemical properties have been investigated in detail.1.A micro/nano structure Sb4O5Cl2-CMK-5 composite was obtained through a solvothermal method,and then used as an anode material for LIBs for the first time.It was found that a reversible capacity of 406.6 mA h g-1 was retained after 100 cycles at a current density of 800 mA g-1,which was superior to that of bare Sb4O5Cl2(90.5 mA h g-1)in the same condition.The superior electrochemical performance of the micro/nano structure Sb4O5Cl2-CMK-5 composite might be attributed to its unique construction,in which the porous nature was feasible to benefit the diffusion of Li-ion and the contact area between the electrolyte and electrode material was efficiently enhanced.On the other hand,CMK-5 coating on the surface of Sb4O5Cl2 could improve the electrical conductivity and cycling stability.2.A new-type Sb8O11Cl2 microrods was synthesized via a one-step solvothermal route,and exhibited a capacity of 723.4 mA h g-1 at a current density of 10 mA g-1 after 20 cycles for SIBs.When further prolonged to the 40th cycle,it still delivered a capacity of 668 mA h g-1,accompanying a capacity retention of 92.3%.In addition,the capacities of 517.4,411.6,247.8 and 191.2 mA h g-1 can be achieved at the current densities of 30,50,100 and 200 mA g-1,respectively.After the high rate test,the capacity restored to 366.2 mA h g-1 when the current density was back to 50 mA g-1.Furthermore,a possible mechanism of Sb8O11Cl2 has also been explored based a series of experimental results.