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以Bi(NO_3)_3·5H_2O和NH_4VO_3为原料,控制水溶液介质p H及反应时间,采用水热合成法制备钒酸铋(BiVO_4)及其复合物(BiVO_4/Bi_6O_6(OH)_3(NO_3)_3).利用X-射线粉末衍射、扫描电子显微镜和紫外-可见漫反射吸收光谱等手段对制备的样品进行了物理表征,结果表明,在控制反应时间为1 h,介质p H值在1.14~9.01之间时,制备的样品为BiVO_4/Bi_6O_6(OH)_3(NO_3)_3复合物,当p H值增加至10.92时为纯BiVO_4;控制介质p H为7.17,反应时间在1~12 h之间时得到BiVO_4/Bi_6O_6(OH)_3(NO_3)_3复合光催化剂,反应时间为18 h时为纯BiVO_4.在可见光(λ≥400 nm)照射下,以有机染料罗丹明B(Rhodamine B,Rh B)为底物,研究不同条件制备的BiVO_4或者复合物为光催化剂的光催化特性,发现p H=7.17,水热反应12 h得到的催化剂(BiVO_4/Bi_6O_6(OH)_3(NO_3)_3)光催化降解活性高于对照制备的纯BiVO_4.同时在可见光照射下,BiVO_4/Bi_6O_6(OH)_3(NO_3)_3亦可以有效降解无色小分子2,4-二氯苯酚(2,4-Dichlorophenol,2,4-DCP),说明氧化过程涉及到光催化过程.分析BiVO_4/Bi_6O_6(OH)_3(NO_3)_3复合光催化剂对Rh B光催化降解过程中活性物种,表明在降解过程中主要涉及空穴和超氧氧化,O_2·~-起主要作用. 相似文献
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InGaAs/InP超晶格材料的GSMBE生长研究 总被引:2,自引:2,他引:0
在国产第一台CBE(Chemicalbeamepitaxy)设备上,用GSMBE(Gassourcemolecularbeamepitaxy)技术在国内首次研究了InGaAs/InP匹配和应变多量子阱超晶格材料的生长,用不对称切换方法成功地生长了高质量的匹配和正负应变超晶格材料,并用双晶X-射线衍射技术对样品进行了测试和分析.结果表明,我们在国产第一台CBE设备上用GSMBE技术采用非对称切换方法生长的超晶格材料质量很好. 相似文献
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A dense La0.8Sr0.2Ga0.83Mg0.17O2.815 electrolyte in pure perovskite phase was prepared by a polyacrylic acid assisted solid state reaction method, and the effects of La source on the structure and electrochemical performance were also studied. By means of XRD and SEM, the structure of this material was characterized, and the electrochemical properties were studied through AC impedance diagram. The results show that the sample presents a single perovskite-type phase after sintering at 1 450 ℃ and the relative density is 94%. The specimen has the lower activate energy and higher electrical conductivity at 600 ℃. There are two different activation energy at the turning point of 650 ℃, which are 74.6 and 42.4 kJ·mol-1, respectively. The electrical conductivity is 0.057 S·cm-1 and 0.017 S·cm-1 at the temperature of 800 ℃ and 600 ℃, respectively. 相似文献
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