Xiaoe Xie

Zn–Al layered double oxides as high-performance anode materials for zinc-based secondary battery

In this work, Zn–Al layered double oxides (Zn–Al-LDO) were prepared via a facile hydrothermal method, followed by calcination treatment in an air atmosphere, and evaluated as anode materials of Zn/Ni batteries. The morphology and structure of as-prepared Zn–Al-LDO and its precursor Zn–Al layered double hydroxide (Zn–Al LDH) were investigated through Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Compared to the Zn–Al-LDH precursor, Zn–Al-LDO possesses higher discharge capacity, better reversibility and longer cycle life. The discharge capacity of Zn–Al-LDO remains about 460 mA h g−1 after 1000 cycles. In particular, good rate performance can be observed for a Zn–Al-LDO electrode. The superior properties could be ascribed to improved charge conductivity and the absence of carbonate anions, which make migration of hydroxyl anions smooth to meet the requirements of the electrochemical reaction of the electrode.

A novel ZnO@Ag@Polypyrrole hybrid composite evaluated as anode material for zinc-based secondary cell.

A novel ZnO@Ag@Polypyrrole nano-hybrid composite has been synthesized with a one-step approach, in which silver-ammonia complex ion serves as oxidant to polymerize the pyrrole monomer. X-ray diffraction (XRD) and infrared spectroscopy (IR) show the existence of metallic silver and polypyrrole. The structure of nano-hybrid composites are characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM), which demonstrates that the surface of ZnO is decorated with nano silver grain coated with polypyrrole. When evaluated as anode material, the silver grain and polypyrrole layer not only suppress the dissolution of discharge product, but also helps to uniform electrodeposition due to substrate effect and its good conductivity, thus shows better cycling performance than bare ZnO electrode does.

Green preparation and characterization of a novel heat stabilizer for poly(vinyl chloride)–hydrocalumites

Hydrocalumites are successfully prepared by using Ca(OH)2, Al(OH)3 and Na2CO3 with different reaction times and crystallization times. The as-prepared samples are characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The results show that the as-prepared sample with the reaction time and crystallization time both being 4 hours can be seen as pure hydrocalumite, and shows higher crystallinity and more regular crystals than the other samples. The different as-prepared samples were mixed with PVC resin. Thermal aging and Congo red test of the resulting PVC composites were carried out in a thermal aging test box at 195 ± 1 °C. The results show that all the as-prepared samples used as single thermal stabilizers could enhance both the long-term thermal stability and initial thermal stability of PVC. Especially, the as-prepared sample with the reaction time and crystallization time both being 4 hours has better thermal stability than the other samples. And thermal aging tests of PVC with varying amounts of hydrocalumites shows that 4 phr is the optimum amount of hydrocalumite filler.