MoS2/C复合纳米管的合成

在900℃氢气气氛下,通过热分解载有硫代钼酸铵的碳纳米管前驱物得到MoS₂/C复合纳米管.通过粉末X射线衍射(XRD)、拉曼光谱(Raman)、高分辨透射电镜(HRTEM)和X射线能量散射仪(EDS)等方法对其形貌、结构和成分进行了表征.结果表明,所合成物质是一种由两种材料组成管壁的新型纳米管.     

三维分级结构氢氧化钴的合成

以硝酸钴为钴源,采用十六烷基三甲基溴化铵(CTAB)辅助,通过水热法合成了具有三维分级结构的β-Co(OH)2微球.采用粉末X射线衍射(XRD)、能谱元素分析(EDS)和扫描电镜(SEM)对产物进行表征.实验结果表明,产物β-Co(OH)2为由直径1～2μm和厚度约500nm的纳米板组装而成的微球.考察了CTAB的浓度、pH值和温度对产物形貌的影响.结果表明,CTAB的浓度和pH值对最终产物的形貌具有重要影响,而当水热温度在140～180℃区间内,反应温度对产物的形貌无影响.通过监控不同反应时间所获产物的形貌,初步探讨了三维结构的β-Co(OH)2的生长机制.     

具有主导晶面的BiOIO3/BiOCl异质结制备与光催化性能

分别以乙二醇/去离子水为溶剂,通过溶剂热/水热法分别制备了具有不同主导晶面的BiOIO₃/{110}BiOCl和BiOIO₃/{001}BiOCl异质结。采用X射线衍射、扫描电子显微镜、能量色散谱和紫外可见漫反射光谱对制备的BiOIO₃/BiOCl光催化剂进行了表征。在可见光照射下,通过对罗丹明B和苯酚水溶液的光催化降解,考察了BiOIO₃/BiOCl异质结的光催化活性。结果显示25%BiOIO₃/{110}BiOCl异质结具有最高的光催化效率。BiOIO₃/{110}BiOCl较好的光催化性能是由于其在可见光区较强的光吸收,以及异质结结构和BiOCl所具有的(110)主导晶面有利于光生载流子的分离。超氧自由基(·O₂^-)和空穴(h⁺)是光催化过程中的主要活性物质。此外,根据实验结果探讨了光催化性能增强的机理。     

AgIO_3 Composited with m-BiVO_4 as Enhanced Visible-light Heterojunction Photocatalysts for the Elimination of Aqueous Organic Pollutants

The heterojunction strategy was used to overcome the drawbacks of AgIO_3 for its wide band gap and of BiVO_4 for its low charge-separation efficiency. The photocatalytic per-formances of the as-prepared AgIO_3/BiVO_4 were assessed by the photodegradation of rhodamine B(Rh B) and tetracycline hydrochloride antibiotics(TC) under visible-light irradiation. All the as-prepared samples showed remarkable enhanced photocatalytic efficiency than pure AgIO_3 and BiVO_4. Especially, 40% AgIO_3/BiVO_4 exhibited optimum photocatalytic activities among all the prepared samples. The improvements may be ascribed to the synergetic effect between AgIO_3 and BiVO_4 including matching potentials and effective charge separation. Radical trap experiments determined that h+ radical plays a significant role in the photodegradation of RhB while e-is not the dominating reactive species.     

水热法合成双金属多元型的Mo1.8W16.2O49纳米棒

近年来,纳米材料在电子学[1]、光电子学[2]和存储元件[3]等技术的发展方面起到至关重要的作用。在纳米材料的合成中,过渡金属氧化物的合成越来越受到人们的重视[4,5]。一维过渡金属氧化物纳米材料具有特殊的光学、磁学和电学特性。其中,一维氧化钨(WO3-x,0≤x<3)纳米材料具有很     

新型二元相MoS2/C纳米管的合成和机理研究

在900 ℃氢气气氛下, 通过热分解载有硫代钼酸铵的碳纳米管前驱物得到MoS₂/C二元相纳米管. 通过粉末X射线衍射(XRD)、高分辨透射电镜(HRTEM)、扫描电镜(SEM)和X射线能量散射仪(EDS)等方法对其形貌、结构和成分进行了表征. 结果表明, 我们合成了一种由两种材料组成管壁的新型纳米管, 并对其形成机理进行了研究.     

氧化锌纳米棒的制备和生长机理研究

ZnO nanorods are prepared by different assistants (cetyltrimethylammonium bromide，trisodium citrate and ethylene diamine anhydrous) favored hydrothermal synthesis with Zn(OH)₂ colloid as the precursor. The samples are characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The results show that the as-synthesized ZnO nanorods are of uniform size with 25 nm in diameter and 200～300 nm in length. The effects of the different assistants to the morphology, size and mechanism of nano-ZnO are discussed.     

纳米二氧化钛粉体表面的吸附特征及其对粉体分散性的影响

以四氯化钛(TiCl4)为原料,采用3种不同的沉淀剂制备了纳米二氧化钛粉体.用TG-DTA和FT-IR对前驱体进行了分析.结果表明,不同沉淀剂导致粉体表面状态不同.以乙酸和尿素为沉淀剂的粉体表面不仅沉淀剂可以形成化学吸附,水分子也参与反应并在粉体表面形成-OH基团,而以EDTA为沉淀剂的粉体表面只吸附沉淀剂.煅烧后,用TEM对颗粒形貌进行了表征.实验发现,以EDTA为沉淀剂制备的粉体分散性优于其他沉淀剂制备的二氧化钛颗粒.这些差异主要是由于沉淀剂的性质及其在粉体表面的吸附状态不同.     

Ag/C同轴纳米电缆的制备

采用十六烷基三甲基溴化铵(CTAB)辅助水热法合成了Ag/C同轴纳米电缆,并用SEM、TEM、XRD和EDS对产物进行了表征。结果表明,产物为长达数十微米,内核直径80～100 nm,壳厚约100 nm的纳米电缆。初步探讨了Ag/C同轴纳米电缆的生长机制。     

α-MnO2和β-MnO2纳米棒的制备和催化性能研究

α-MnO₂ and β-MnO₂ nanorods were prepared directly by facile hydrothermal process at 150 ℃ and 220 ℃, respectively. The as-prepared α-MnO₂ and β-MnO₂ nanorods were shown to be phase-pure single crystallites as evidenced by XRD, TEM and SEM results. Further experiments show that the as-prepared α-MnO₂ and β-MnO₂ nanorods have catalytic effect on the oxidation and decomposition of the methylene blue(MB) dye with H₂O₂. The catalytic activity of β-MnO₂ is much higher than that of α-MnO₂.