溶胶络合转化法制备CdS纳米微晶及其特性研究

Synthesis and Characterization of CdS Nanocrystals Prepared by Sol Complex Transformation

依据高分子链上的配位基团与金属离子间络合反应平衡原理以及溶液中双电层扩散模型 ,提出了用溶胶络合转化法在甲壳胺中制备CdS纳米微晶的新方法。采用原子力显微镜 (AFM )、X射线衍射图谱 (XRD)、紫外 -可见吸收光谱 (UV)及激发 -发射光谱等手段研究了甲壳胺膜中CdS纳米微晶的特性 ,室温下的量子尺寸效应由实验得到了证实。此外分别采用Scherrer公式和AFM技术对晶粒尺寸进行了估算与测定 ,并对两种结果进行了比较与分析 ,由这种方法制备的纳米微粒尺度可由实验条件控制在 2～ 1 8nm之间。

AnovelprocessforsynthesisofCdSnanocrystalsinchitosanbysolcomplextransformationmethod ,basedonthereactionmecha nismbetweentheligandsonpolymerchainsandmetalions ,aswellasonthediffusionmodelofdoubleelectricallayersinsolution ,hasbeen putforwardinthispaper .Themorphologystructures,opticalpropertiesoftheCdSnanocrystalsobtainedbythistechnologyhavebeeniden tifiedbyatomicforcemicroscope (AFM ) ,X -raydiffraction (XRD) ,ultraviolet -visibleabsorptionspectra (UV) ,excitationandemissionspectraandtheirquantumsizeeffectsatroomtemperaturewerealsodemonstrated .Thesizeofthenanocrystalsischitosanwasestimatedtobeabout 2～ 1 8nmdependingontheexperimentalconditions.Inaddition ,comparisonoftheresultsforthenanocrystalsizedeterminedbyAFMwiththoseestimatedbyScherrer’sequationwasmadeandthereasonfortheirdifferencewasalsoanalyzed .