Preparation and application of functionalized nanoparticles of CdS as a fluorescence probe

CdS nanoparticles have been prepared and modified with mercaptoacetic acid. The functionalized nanoparticles are water-soluble and biocompatible. They could be used as a fluorescence probe in the determination of bovine serum albumin (BSA), which was proved to be a simple, rapid and specific method. In comparison with single organic fluorophores, these nanoparticle probes are brighter, more stable against photobleaching, and do not suffer from blinking. Under the optimum conditions, the response is linearly proportional to the concentration of BSA between 0.1 and 3.2 μg ml⁻¹, and the limit of detection is 0.08 μg ml⁻¹.     

室温水相合成CdTe/CdS核/壳结构量子点

开发了一种以聚乙烯吡咯烷酮为分散剂和稳定剂经条件温和的室温水相合成光谱可调的水溶性CdTe/CdS核/壳结构量子点的方法:向新鲜制备的CdTe量子点溶液中加入硫源,继续反应即可生成CdS壳层,通过控制硫源的浓度即可控制CdS壳层厚度,从而调节光谱性质和增强稳定性.采用XRD、TEM、HRTEM、荧光光谱以及紫外-可见光...     

CdS纳米晶颗粒薄膜的制备及其光学特性研究

采用化学浴沉积法,以CdCl2·H2O、CS(NH2)2、NH4Cl、NH3·H2O和去离子水作为反应前驱物,在不同的氨水浓度下制备CdS纳米晶颗粒薄膜.通过扫描电镜、X射线衍射、X射线能量色散谱、紫外-可见光透射光谱、椭圆偏振光谱等方法,研究了反应前驱物中氨水浓度对CdS纳米晶颗粒薄膜的表面形貌、晶体结构、S/Cd原子比、光透过率、光学带隙、折射率、消光系数和光学吸收边等物理性能的影响.结果表明:反应前驱物中氨水浓度在0.4～1.0mol/L范围内,可以在衬底上形成均匀致密的CdS纳米晶颗粒薄膜.随着氨水浓度的增加,CdS纳米晶的平均晶粒尺寸逐渐减少,S/Cd原子比逐渐增加,由富Cd型转变为富S型,禁带宽度逐渐增加.在500～1000 nm波段内,折射率的平均值为1.75;消光系数k小于0.07.     

CdS nanocrystallites sensitized ZnO nanorods with plasmon enhanced photoelectrochemical performance

A sandwiched structure of CdS/Ag/ZnO nanorod photoanode exhibits greatly enhanced photoelectrochemical activity for solar hydrogen generation, due to synergistic effect of CdS nanocrystallites and plasmonic Ag nanoparticles for the enhanced optical absorption and the promoted charge carrier separation.     

表面过剩S2-对CdS光催化的影响与带位匹配

用ESR方法研究了硫化镉超微粒子表面被不同浓度的过剩硫离子S2－改性后对其光诱导电子转移及底物的氧化还原反应进程的影响.结果表明,在较高浓度下光还原反应易于进行.若所用底物的氧化还原电位E0为负值,在无过剩S2－存在及低浓度S2－环境中不发生光还原反应,但却可在高浓度S2－环境发生反应; 若底物的E0为正值,则在无硫离子及较低硫离子浓度下能够发生的光氧化反应,在高浓度时则被完全抑止.这是由于表面过剩S2－的作用,改变了底物的氧化还原电位与半导体超细微粒带隙间的匹配关系.根据Langmuir 等温吸附模型,进一步导出了修饰物的浓度c与平带电位负移值间的关系表达式ΔEfb=Δ Kc/(1＋Kc).可以合理解释修饰物 S2－的浓度越高,Efb负移越大,越有利于光还原反应的实验事实.因此根据需要,适当地选择修饰物并控制浓度,使带隙位置与底物氧化还原电位间能有合适的匹配,有助于调节光化学反应的选择性与方向.     

超薄骨架有序介孔CdS/NiS的制备及光催化产氢性能

采用有序介孔氧化硅为硬模板, 通过纳米浇筑法制备了由螺旋骨架构建的有序介孔硫化镉(CdS)光 催化材料. 该光催化材料具有约5 nm厚的超薄骨架和大的比表面积(238 m²/g), 能有效缩短光催化反应中 光生电荷迁移到表面进行反应的距离并同时提供更多的反应活性位点, 从而增强光催化性能. 通过原位化学沉积法将不同量的助催化剂硫化镍(NiS)沉积到有序介孔CdS表面, 得到了一系列超薄骨架有序介孔CdS/NiS复合光催化材料. 可见光照射下的光催化产氢活性测试结果表明, 负载适量NiS的有序介孔CdS具有显著增强的光催化产氢活性(3.84 mmol?h^-1?g^-1), 约为负载相同量NiS的普通商业化CdS材料(0.22 mmol?h^-1?g^-1)的17.5倍.     

水相法制备CdS纳米棒

水相法制备CdS纳米棒;cds纳米棒;水相溶液;晶体生长;乙二胺     

CdS/石墨烯纳米复合物的可见光催化效率和抗光腐蚀行为

制备了一系列CdS纳米晶/石墨烯(CdS/GR)复合物,并在可见光照条件下评价了其光催化降解亚甲基蓝的光催化效率和抗光腐蚀行为. 研究表明,石墨烯的引入加速了CdS纳米晶(NCs)光生电子的迁移速率,抑制了其光生电子-空穴的复合,有效改善了其光催化降解有机污染物的性能. CdS/GR复合物中的石墨烯含量显著影响其光催化效率,其中石墨烯含量为4.6%的光催化剂效率最高,其光电流是CdS NCs的2.3倍. 利用光电化学和X射线衍射技术进一步证实,石墨烯的引入抑制了CdS NCs光腐蚀的发生,提高了CdS/GR复合物的光催化稳定性.     

Understanding the junction degradation mechanism in CdS/CdTe solar cells using a Cd-deficient CdTe layer

It is known that CdTe solar cells are often degraded under solar illumination. But the degradation mechanism is not fully proved because it does not appear consistently. The junction degradation in CdS/CdTe solar cells was investigated using a CdTe layer with Cd deficient composition, where Cd vacancy concentration is high. It was found that the Cu atoms easily filled the Cd vacancies in CdTe and transport to junction area from Cu back contact. PL measurement and spectral quantum efficiency measurement showed that the incorporation of Cu atoms in CdS forms a defect energy level at 1.55 eV below the conduction band in CdS. As a result, the junction built-in potential is decreased and light penetration into CdTe absorber is shielded. For reliable and stable CdTe cells, the formation of Cd vacancy in CdTe should be avoided by careful control of CdTe.