共沉淀法制备Eu_2Zr_2O_7/ZrO_2(3Y)纳米粒子.用XRD,DTA-TG,SEM对材料的物相变化及形貌进行表征,对粉体制备过程中晶粒合成动力学进行分析.结果表明:将两种不同溶液分别处理后制备得到Eu_2Zr_2O_7粉体和ZrO_2(3Y)前驱体按不同体积比混合研磨后,置于马弗炉中600℃煅烧2.5 h合成出近似球形、粒径均匀且分散性好的Eu_2Zr_2O_7/ZrO_2(3Y)纳米粒子.Eu_2Zr_2O_7前驱体物相变化分3个阶段,用Doyle-Ozawa和Kissinger法分别计算各阶段的表观活化能,其平均值分别为108.29、142.23、412.93 k J/mol;晶粒生长活化能为24.91 k J/mol.
MoN was prepared by rare earth Gd thermaldiffused permeation method via solid–gas interface reaction using（NH_4）_4[NiMo6O_24H_6]·7H_2O（abbreviated as NiMo6） as the precursor. Thermo-gravimetric differential thermal analysis（TG–DTA） was used to study the product＇s stability. The results of X-ray diffractometer（XRD）and X-ray photoelectron spectroscopy（XPS） indicate that a new hexagonal crystal MoN forms after the rare earth gas permeation and Gd3＋are diffused as substitution ions into the crystal lattice of MoN, and the surface valence of elemental content was measured by XPS. The conductivity results by direct current（DC） four-probe method show that MoN obtained from the Gd thermal permeation exhibits conductor character in the temperature range of 298–740 K and semiconductor behavior in 740–800 K.
To improve the performance of battery cathode materials that consist of carbonaceous organic material, carbon coatings on lithium iron phosphate （LiFePO4/C） materials were synthesized by different carbon sources. LiFePO4/C was synthesized by a combination method of sol-gel and gas-phase diffused permeation. LiFeO4/C materials were prepared by coating different carbon con- tents. High-performance composite materials were pre- pared by combining carbon with element doped by two modified methods. The elements of Fe and C came from Fe3＋ and sucrose, glucose, citric acid. Thermogravimetry- differential thermal analysis （TG-DTA）, X-ray diffrac- tometer （XRD）, scanning electron microscope （SEM）, cycle voltammetry （CV）, and charge-discharge test were used to characterize and test the surface morphology, structure, and electrochemical performance. The results show that LiFePO4/C synthesized with sucrose has higher specific discharge capacity than the other materials. The specific discharge capacity of this material is 84.27 mAh.g-1. The capacity retention could attain 94 % of the initial discharge capacity after 30 cycles, showing good electrochemical performance.
Xin LiYu Zhi JiangXi Kun LiHai Xia JiangJun Long LiuJun FengShi Bin LinXin Guan
