硫化银论文硫化银 二硫化钼 硫化镉 反相微乳法 半导体纳米材料

硫化银论文硫化银 二硫化钼 硫化镉 反相微乳法 半导体纳米 硫化银论文硫化银 二硫化钼 硫化镉 反相微乳法 半导体纳米材料 【中文摘要】过 渡金属硫化物MoS2、PdS、Ag2S、Bi2S3和In2S3等具有较窄的能带系、高的光吸收 系数及良好的化学稳定性可以作为贵金属替代物用于光催化制氢领域并显示了潜在 的应用前景。采用纳米制备技术制备形貌和尺寸可控的硫化物纳米晶研究纳米晶晶 面取向对电子传输的影响是非常值得的研究方向。本文在硫化物纳米晶的合成及光 学性质方面进行了大量探索取得以下主要研究成果:通过对不同微乳体系稳定性及 增溶性的尝试和研究本文选用TX-100/环己烷/正己醇/水反相微乳体系以TAA 硫代 乙酰胺为硫源、AgNO3为银源并在反应体系中加入六齿配体EDTA乙二胺四乙酸以 调控Ag的释放速度在室温条件下合成了高晶化度、直径为2550 nm、长达数微米的 蠕虫状Ag2S纳米晶。其紫外-可见吸收光谱显示该纳米晶在290 nm处呈现强吸收与 体相Ag2S1240nm相比其吸收边发生了明显的蓝移明蠕虫状Ag2S纳米晶具有明显 的量子尺寸效应。而且通过调控微乳体系中ω0 水与表面活性剂物质的量浓度之比、 Ag与EDTA的物质的量的比、陈化时间等可以实现对产物尺寸和形貌的调控。采用 /正己醇/水反相微乳体系以四硫代钼酸铵为前驱体盐酸羟胺为 【英文TX-100/环己烷 摘要】Metal chalcogenides such as MoS2 PdS Ag2S Bi2S3 and In2S3 are narrow band gap semiconductors with high light absorption coefficient and good chemical stability. Increasing attention is now being focused on their potential applications as promising candidates for Pt a co-catalyst in photocatalysis. The study on controlling the size and morphology of metal sulfides and the influence of crystalline plane on the electron-hole transport is a very important subject for the development of efficient photocatalysts. The present thesis focuses on the preparation and optical properties of nanosized metal sulfides with unique morphology and obtained the following main results.High-aspect-ratio of worm-like Ag2S nanocrystal with length up to several micrometers and a diameter of 2550 nm has been successfully prepared by a Triton X-100/cyclohexane/hexanol/water W/O reverse microemulsion in the presence of TAA Thioacetamide as a sulfur source and EDTA ethylene diamine tetraacetic acid as a chelating ligand. The as-synthesized Ag2S nanocrystals exhibit strong absorption in UV region with an absorption edge at about 290 nm compared to the absorption band of bulk Ag2S 1240nm Eg1.0eV. A significant blue-shift of the UV-Vis absorption spectra of the worm-like Ag2S over the bulk Ag2S reveals that the as-prepared worm-like Ag2S exhibits obvious quantum confinement effects. In addition the morphology and size of Ag2S nanocrystal can be readily controlled by modulating the molar ratio of Ag to EDTA the molar ratio of water to surfactant ω0 and the aging time.Similarly chain-like MoS2 assemblies consisted of hexagonal MoS2 nanocrystals 2060 nm have been synthesized in a Triton X-100/cyclohexane/hexanol/water W/O reverse microemulsion using NH42MoS4 as a precursor of molybdenum and NH2OH?HCl as a reducing agent. UV-Vis absorption spectra typically exhibits a strong absorption in the blue region with a maximum at 276 nm and a weaker broad absorption in the visible region of 400 nm. Compared to the absorption band of bulk 2H-MoS2 1040 nm the absorption spectra of as-obtained MoS2 chains is of significant blue-shift which may originate from to the position-dependent quantum-size and shape effect. Nano-sized CdS and CdS/Ag2S nano-composites were also synthesized by a hydrothermal treatment followed by a W/O microemulsion process. The results show that the hydrothermal method in microemulsion is an effective method to prepare CdS nanomaterials of hexagonal structure at low temperature. 【关键词】硫化银 二硫化钼 硫化镉 反相微乳法 半导体纳米材料 【采买全文】 1.3.9.9.38.8.4.8 1.3.8.1.13.7.2.1 同时提供论文写作定制和论文发表服务.保过包发. 【说明】本文仅为中国学术文献总库合作提供无涉版权。作者如有异议请与总库或学校联系。 【英文关键词】Silver Sulfide Molybdenum Disulfide Cadmium Sulfide Reverse Microemulsion Nano-sized semiconductors 【目录】W/O反相微乳技术合成窄带系硫化物纳米晶摘要3-4Abstract4-51 绪论8-231.1 半导体纳米材料的研究进展8-151.1.1 半导体纳米材料的特性8-101.1.2 半导体纳米材料的制备10-121.1.3 金属硫化物半导体纳米材料在光催化方面的应用12-131.1.4 金属硫化物作为助催化剂对半导体光催化性能的影响13-151.2 微乳液技术制备半导体纳米材料15-221.2.1 反相微乳技术制备纳米材料的特性16-171.2.2 反相微乳法合成纳米材料的影响因素17-201.2.3 反相微乳法在制备金属硫化物半导体纳米材料的应用20-221.3 论文选题意义及目的22-232 微乳体系的配制23-282.1 实验部分23-272.1.1 主要化学试剂及仪器232.1.2 CTAB/正丁醇/正辛烷/水微乳体系23-252.1.3 Triton X-100/环己烷/正己 25-272.2 小结27-283 反相微乳法合成蠕虫状纳米材料Ag_2S硫化银醇/水微乳体系 28-373.1 实验部分28-303.1.1 主要化学试剂及仪器28-293.1.2 蠕虫状纳米Ag_2S 的制备29-303.1.3 产物测试仪器及条件303.2 结果与讨论30-363.2.1 不同硫源对产物晶相 及形貌的影响30-323.2.2 不同配体对产物形貌的影响323.2.3 陈华时间对产物形貌的影响32-333.2.4 ω_0 对产物形貌的影响33-343.2.5 配体EDTA 的用量对产 -353.2.6 紫外-可见光谱35-363.3 小结36-374 反相微乳法合成链状物形貌的影响34 结构纳米材料MoS_2二硫化钼37-474.1 实验部分37-404.1.1 主要化学试剂和仪器37-384.1.2 链状纳米MoS_2 的制备38-404.1.3 产物测试?瞧骷疤跫?04.2 结果与讨论40-464.2.1 水热微乳处理对产物晶相的影响40-414.2.2 退火温度及酸度对产物晶相的影响41-424.2.3 退火温度及酸度对产物形貌的影响42-434.2.4 ω_0 值对产物形貌的影响43-444.2.5 陈华时间对产物形貌的影响44-454.2.6 紫外-可见光谱45-464.3 小结46-475 水热微乳法制备纳米CdS 及CdS/Ag_2S 的探索性研究47-545.1 实验部分47-505.1.1 主要化学试剂与仪器47-485.1.2 微乳法及水热微乳法制备CdS 纳米材料48-495.1.3 CdS/Ag_2S 纳米复合材料的制备495.1.4 产物测试仪器及条件49-505.2 结果与讨论50-535.2.1 水热微乳法对产物CdS 物相的影响50-515.2.2 水热微乳法对CdS 产物形貌的影响515.2.3 CdS/Ag_2S 纳米复合材料的初步实验结果51-535.3 小结53-54结论54-55参考文献55-63攻读硕士学位期间发表学术论文情况63-64致 谢64