Adjustable Luminescence of SrAl2O4：Eu^2＋ , Dy^3＋ Assembled in Zeolite

Capsulating guest into the nanometer yoids of zeolites is a effective way to form novel host-guest material. In our work, stoichiometric SrAl2O4: Eu^2 , Dy^3 sol guest was prepared by sol-gel method and assembled into the nanometer channels of zeolite ZSM-5 host through mechanical mixing, hydrothermal reaction and microwave heating reaction, respectively. After being reduced and diffused in a microwave muffle, the fluorescence spectra of the host-guest materials exhibit remarkable blue shifts in comparison of that of SrAl2O4 : Eu^2 , Dy^3 . Some interesting phenomena in the assembled hostguest materials are that the after-glow emission spectra exist two bands at about 400 nm and 517 nm and the relative strengths of these two bands can be adjusted by changing the assembly methods and the assembly concentration. These are attributed to the fact that the phosphor was capsulated into the voids of zeolite ZSM-5 and generated the quantum size effect and the host-guest effect.     

铝阳极氧化多孔膜的制备和应用研究

介绍了以高纯铝为原料采用二次阳极氧化技术制备铝阳极氧化多孔膜的工艺条件，并对以其作为功能膜进行模板组装方面的应用作了研究。     

Hydrothermal synthesis and crystal structure study of two novel 3-D mellitates {Nd2[C6（COO）6] （H2O）6} and {Ho2[C6（COO）6]（H2O）6}

Two novel 3-D coordination compounds, Nd2[C6（COO）6]（H2O）6 （1）and Ho2[C6（COO）6]（H2O）6 （2）, were hydrothermaily synthesized from mellitic acid and neodymium perchlorate （or holmium perchlorate） in the alkaline aqueous solution and characterized with elemental analysis, TG, IR spectrum, and single crystal X-ray diffraction. The two compounds were isostructural and crystallized in the orthorhombic system, space group Pnnm, with a=1.3531 （4） nm, b=0.6687 （2） nm, c=1.0224（3） nm, V=0.92523（5） nm^3, Z=4, D=2.630 g/cm^3, F（000）=696.0, Goof=1.052. Final R indices [1 〉2∑（Ⅰ）]： R1=0.0195, wR2=0.0382 for 1; a=1.3411 （2） nm, b=0.6586（1） nm, c=1.0116（2） nm, V=0.8935（3） nm^3, Z=4, D=2.877 g/cm^3, F（000）=724.0, Goof=1.061. Final R indices [1 〉2∑（Ⅰ）]： R1=0.0200, wR2=0.0479 for 2. In the two compounds 1 and 2, the mellitic acid ligand, in which all the carboxylate groups were deprotonated, had only one kind of coordination mode to bridge metal ions to form four-connected three-dimensional diamondiod networks.     

纳米SiO_2/Au复合粒子的制备及其性质表征

通过改进的方法制备了金壳包覆二氧化硅纳米复合粒子. 二氧化硅和金纳米粒子分别通过Stober法和化学还原法制备. SEM分析表明, 都呈现出单分散的球状分布, 粒径为300和100 nm左右. 制备的纳米复合粒子通过TEM, UV-Vis-Near-IR, FTIR来表征和研究, 结果表明结合柠檬酸钠与硼氢化钾还原法制备所得到的SiO_2/Au复合粒子表层光滑, 完整, 没有团聚现象. SiO_2/Au-3的光学共振峰比SiO_2/Au-1和SiO_2/Au-2有红移. 傅立叶红外光谱研究表明形成SiO_2/Au核-壳结构后, Si-O-Si和Si-OH的键会明显减弱.     

硅酸盐体系长余辉发光材料的研究进展

硅酸盐体系长余辉发光材料因具有优异的发光性能而成为一类重要的能源材料和节能材料.综述了硅酸盐体系长余辉发光材料的研究进展,指出了它的特点和优势,总结了它的制备方法,概括了长余辉发光模型,并提出了今后研究和应用的方向.     

扫描电位沉积法制备Bi-Pt合金膜及其电催化性能的研究

采用扫描电位沉积法在-0.8～-1.1 V电势区间内循环扫描,从有机体系中制备得到Bi-Pt合金膜,通过扫描电镜观察,能量色散谱(EDS)和X射线衍射(XRD)分析研究了该膜层的形貌、元素组成及电催化性能.结果表明,电沉积得到的Bi-Pt合金膜均匀而致密,粒径约为20 nm,合金膜由1.06%Pt和98.94%Bi(质量分数)组成;Bi-Pt合金膜对诸如甲醇和NO-2具有良好的电催化性能,这种Bi-Pt电极可能在环境探测上得到应用.     

Preparation of Phosphors MAl_2O_4∶Eu~(2 )(M=Ca,Sr,Ba) by Microwave Heating Technique and Their Phosphorescence

1 ＩｎｔｒｏｄｕｃｔｉｏｎＭＡｌ2 Ｏ4∶Ｅｕ2 (Ｍ =Ｃａ ,Ｓｒ ,Ｂａ )ｈａｖｅｂｅｅｎｋｎｏｗｎａｓｅｘｃｅｌｌｅｎｔｐｈｏｓｐｈｏｒｓｗｉｔｈｅｍｉｓｓｉｏｎｃｏｌｏｒｓｆｒｏｍｂｌｕｅｔｏｇｒｅｅｎｕｎ ｄｅｒｕｌｔｒａｖｉｏｌｅｔａｎｄｃａｔｈｏｄｅ ｒａｙｅｘｃｉｔａ ｔｉｏｎ[1～ 3].Ｓｔｕｄｉｅｓｏｎｐｈｏｓｐｈｏｒｓｗｅｒｅｍｏｓｔｌｙｐｅｒｆｏｒｍｅｄｉｎ 1 960ｓ′ａｎｄｅａｒｌｙ 1 970ｓ′ｍａｉｎｌｙｆｏｒｌａｍｐａｎｄｃａｔｈｏｄｅ ｒａｙｔｕｂｅａｐ ｐｌｉｃａｔｉｏｎ .Ｉｎ 1 990…     

TiO2光催化剂失活与再生的研究

以甲基橙的降解为实例研究了TiO2光催化剂的使用活性、失活及再生等问题.在本实验条件下,新制光催化剂对甲基橙的降解率η为61%;5、6、10、12次使用后,η分别降至58%、48%、27%、13%.结果表明,光催化剂5次使用内,活性基本不变,12次使用后,活性基本丧失.对于失活光催化剂,采用3种方法对其活性进行再生:蒸馏水中超声20min,并辅以紫外光照;0.1mol/L H2O2水溶液中超声20min,并辅以紫外光照;450℃高温下焙烧30min.对于6次使用光催化剂,上述3种方法可使η分别恢复至60%、61%、56%;10次使用光催化剂,上述3种方法可使η分别恢复至30%、63%、61%;12次使用光催化剂,上述3种方法可使η分别恢复至19%、29%、60%.     

聚苯乙烯/镍核壳结构纳米微粒的制备

以磺化聚苯乙烯核壳结构凝胶粒子为模板,采用化学吸附和化学还原的方法,合成了聚苯乙烯/镍核壳复合粒子.讨论了pH值、温度、溶剂对复合粒子的影响.采用TEM、XRD对其结构、形貌进行了表征.结果表明,在所选择的实验条件下,成功地合成了以聚苯乙烯为核、镍纳米粒子为壳的核壳结构复合微球.