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Crystalline tin oxide nanoparticles were synthesized by the direct precipitation from the starting material granulated tin. TG-DTA of the precursor showed a heavy weight loss at about 130℃ accompanied by an endothermic peak, two exothermic peaks above 200℃ accompanied by small weight loss indicated the decomposition and the oxidation of residual NO3- ion and PEG. XRD showed that obtained particles agreed well with the determination result of bulk SnO2. The broadened XRD patterns became sharper as the calcining temperature turned to higher, it was indicated that the growth of the particle was exhibited. The surface area of the particles calcined at 300℃ was 161.1m2·g-1 and declined as the calcining temperature turned to higher. TEM showed an heavier agglomeration at higher temperature. 相似文献
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高度分散的Pt/TiO2的制备及光催化活性 总被引:1,自引:0,他引:1
用柠檬酸作为空穴捕获剂和分散剂, 在温和条件下用光催化还原法将3 nm金属铂沉积在7 nm的锐钛矿相及介孔二氧化钛纳米晶表面. TEM观察显示铂的负载量为w=1.0%时, 多数二氧化钛纳米晶表面沉积了岛状的铂团簇, XPS和电子衍射结果表明铂以游离态存在. 负载w=1.0%~2.0%铂的TiO2在苯酚光氧化反应中活性显著提高. Pt/TiO2在氨气中经550 ℃氮化, 可制得氮掺杂的Pt/TiO2可见光光催化剂, 氮化过程中铂团簇没有烧结和显著长大. 相似文献
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TiO2修饰MCM-41的结构表征及光催化苯酚降解活性 总被引:6,自引:0,他引:6
以钛酸丁酯为前驱体,合成了呈单层和双层分散状态的TiO 相似文献
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三氯化钛水解法制备纳米金红石相氧化钛粉体 总被引:6,自引:0,他引:6
以TiCl_3为原料,通过控制盐浓度和水解温度可以在温和条件下制备出晶粒尺 寸为6~8 nm的金红石相氧化钛粉体,比表面为74.55 m~2/g,TEM照片显示粉体, 比表面为74.55 m~2/g, TEM照片显示粉体为钛状。苯酚的光催化降实验表明这种粉 体具有与P-25相关的光催化活性。采用(CH_3)_4NOH为注定剂,粉体经800 ℃煅烧 ,晶相由锐钛相全部转变为金红石相。 相似文献
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单分散超细ZnO粉体的制备与表征 总被引:8,自引:0,他引:8
Monodispersed superfine ZnO powders with particle size of about 200~400nm were successfully prepared by the decompressed distillation process with n-butyl alcohol as the solvent. The starting materials were Zn(NO3)2·6H2O and NH3·H2O. TG-DSC, XRD, TEM and BET surface areas techniques were used to characterize the precursor and as-prepared superfine ZnO powders. In the preparation process of superfine ZnO powders, two techniques including the decompressed distillation with n-butyl alcohol and washing with absolute ethanol were used to avoid agglomeration. It is showed that the decompressed distillation process has a better effect in avoiding ag-glomeration than washing with absolute ethanol. The precursor obtained by the decompressed distillation technique has a lower calcination temperature than the one obtained by washing with absolute ethanol. Zincite phase of ZnO with some impurities was obtained when the precursor was calcined at 200℃ for 2h. After it was calcined at 300℃ for 2h, pure superfine ZnO powder was obtained. 相似文献
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