Preparation of ZnSe Nanoparticles via Low‐Temperature Solid Phase Process

ZnSe nanoparticles were prepared from ZnCl₂, Se and KBH₄ in the presence of cetyltrimethyl ammonium bromide (CTAB) through a room temperature solid phase process. The products were characterized with x‐ray diffraction (XRD), transmission electron microscope (TEM), and energy dispersive analysis of x‐ray (EDAX). The results show that the cubic zincblende phase ZnSe nanoparticles can be obtained using this simple method. The size of nanoparticles was evaluated to be from 8 to 30 nm.     

Synthesis of Anisotropic ZnSe Nanorods with Zinc Blende Crystal Structure

Compared with the well‐explored cadmium‐based one‐dimensional nanorods (NRs), it is still a challenge to produce heavy‐metal‐free II–VI semiconductor analogues with a controlled size, shape, and crystal structure. Herein, a synthetic strategy towards ZnSe NRs with a zinc blende crystal structure is presented, where use of the anisotropic nuclei produced via a high‐temperature selenium injection favors anisotropic growth. Elongated ZnSe NRs were produced from anisotropic ZnSe nuclei, while spherical ZnSe nanocrystals were obtained starting from isotropic nuclei. The different free energy at (111) and (220) planes in anisotropic ZnSe nuclei induces the anisotropic growth of (111) plane for ZnSe NRs. Proper choice of the capping ligand (1‐dodecanethiol) has an important implication for the formation of anisotropic ZnSe nuclei and also allows the control of the diameter of the final ZnSe NRs by limiting the growth of the (220) crystal plane of anisotropic ZnSe nuclei.     

常压MOCVD法生长的p型ZnSe及其光电特性

本文通过常压MOCVD方法,利用NH₃气作为受主掺杂源,在(100)方向的GaAs衬底上生长了ZnSe:N膜。通过测量77K温度下光致发光光谱。观测到了由于掺氮引起的自由到束缚发射(FA)和深中心复合(SA).在低掺杂浓度下FA起主要作用,随着NH₃气浓度增加,FA和SA带的强度随之增强,在重掺杂下SA带成为主要,同时带的半宽度展宽。室温下霍尔测量的结果表明。低掺杂浓度下ZnSe:N膜呈高阻态,而在高掺杂浓度下外延膜呈现P型电导,载流子浓度P～1016cm³.利用p-ZnSe/n-GaAs构成异质pn结,观测到了二极管的整流特性,进一步证实p型ZnSe的实现。     

ZnSe/ZnS平板波导全光调制和电光调制特性

在室温,随着增加入射光强,我们首次在ZnSe/ZnS平板被导中观测到由于“带填充”效应而引起的全光调制和由于施加电场而引起的电光调制特性.     

非线性干涉滤光片N形反射光双稳器件的研究

对Ｎ形反射光双稳器件的结构进行了理论设计和实验研究，对光双稳的重要参数δＩ０、δＩｒ与初始失调量δ之间的关系进行了描绘，并通过引入ＺｎＳｅ薄膜的色散关系，使这一理论方法具有自洽性。最后，文章给出了通过这一方法设计的非线性干涉滤光片Ｎ形反射光双稳器件的实验结果。     

Cr~(2+):ZnSe全固态中红外激光器

建立了一种高质量、高效率全固态中红外激光系统,并对激光输出的效率、光束质量等指标进行了测试。首先,以二极管激光器为泵浦源,Tm~(3+):YAP晶体为增益介质,搭建了输出波长为1.97μm的近红外激光器。然后,以Tm~(3+):YAP激光器为泵浦源,自行开发研制的Cr~(2+):ZnSe单晶为增益介质,搭建了全固态中红外激光器。最后,测试了全固态中红外激光器的光束质量及激光器出光效率,并对谐振腔光效率的理论输出值与实际的激光器出光参数进行了对比。实验结果表明:此全固态中红外激光器的光光转换效率为17.2%,斜率效率为20%,在最高输出能量为3 W时的光束质量(M~2)在x和y方向分别为1.7和1.73,光束基本为圆形的高斯光斑。     

Ultrathin zinc selenide nanosheet-based intercalation hybrid coupled with CdSe quantum dots showing enhanced photocatalytic CO_2 reduction

Fabrication of well-designed heterojunctions is an extraordinarily attractive pathway for boosting the photocatalytic activity toward CO_2 photoreduction.Herein,a novel kind of na nosheet-based intercalation hybrid coupled with CdSe quantum dots(QDs) was successfully fabricated by a facile solvothermal method and served as photocatalyst for full-spectrum-light-driven CO_2 reduction.Ultra-small CdSe QDs were rationally in-situ introduced and coupled with lamellar ZnSe-intercalation hybrid nanosheet,resulting in the formation of CdSe Q.Ds/ZnSe hybrid heterojunction.Significantly,the concentration of Cd~(2+) could change directly the crystallinity and micromorphology of ZnSe intercalation hybrid,which in turn would impact on the photocatalysis activity.The optimized CdSe QDs/ZnSe hybrid-5 composite demonstrated a considerable CO yield rate of the 25.6 μmol g~(-1) h~(-1) without any additional cocatalysts or sacrificial agents assisting,making it one of the best reported performance toward CO_2 photoreduction under full-spectrum light.The elevated CO_2 photoreduction activity could be attributed to the special surface heterojunction,leading to improving the ability of light absorption and promoting the separation/transfer of photogenerated carriers.This present study developed a new strategy for designing inorganic-organic heterojunctions with enhanced photocatalyst for CO_2 photoreduction and provided an available way to simultaneously mitigate the greenhouse effect and alleviate energy shortage pressure.     

Ag/ZnO/ZnSe三元异质结的合成及其可见光光催化性能

以Ag纳米线为模板,通过两步水浴法合成了Ag/Zn O/Zn Se三元异质结光催化材料。利用场发射扫描电子显微镜(FESEM)、X射线能谱仪(EDS)、X射线衍射仪(XRD)以及透射电子显微镜(FETEM)对样品的形貌和结构进行了表征。结果显示,Ag/Zn O/Zn Se三元异质结为蠕虫状的Ag/Zn O二元异质结外镶嵌着Zn Se小颗粒。在可见光下,对比纯Ag纳米线、纯Zn O纳米球、Ag/Zn O异质结对罗丹明B的可见光降解效率,结果发现Ag/Zn O/Zn Se异质结表现出了更高的光催化效率。其光催化性能的提高主要是由于Ag/Zn O/Zn Se异质结的作用促使电子空穴对的分离,降低了电子空穴对的复合机率,从而提高了材料的光催化效率。     

基于弹光调制的红外光谱吸收法在室内VOC检测中的研究

为了保证静态干涉系统在气体定性定最分析方面稳定性高、抗干扰能力强的特点,设计了基于弹光调制实现光程静态扫描的干涉检测系统.系统由红外激光器、起偏器、弹光调制器、检偏器及CCD组成.通过弹光调制器使弹光晶体的主折射率随调制信号周期性的变化,从而产生周期性变化的光程差.通过对调制相位变化的计算,可知得到调制度随晶体长度、调...     

A novel optical nanoprobe for trypsin detection and inhibitor screening based on Mn-doped ZnSe quantum dots

In this paper, a novel optical nanoprobe (Mn:ZnSe d-dots-Arg₆) for trypsin detection and its inhibitor screening has been constructed successfully based on the fluorescence quenching and recovery of Mn:ZnSe d-dots. Mn:ZnSe d-dots would aggregate in the presence of positively charged Arg₆ (six arginine residues) due to electrostatic interactions that result in the fluorescence quenching. Arg₆ can be hydrolyzed into small fragments in the presence of trypsin, and accordingly, the aggregation of Mn:ZnSe d-dots can be prohibited, which lead to the fluorescence recovery. Experimental results show that the recovery in fluorescence intensity is linearly proportional to the concentration of trypsin within the range of 0.1–12.0 μg mL⁻¹ with a detection limit of 40 ng mL⁻¹ under the optimized experimental conditions. We also prove the feasibility of fluorescence recovery of Mn:ZnSe d-dots for trypsin detection through the resonance light scattering (RLS) technique. Additionally, the optical nanoprobe can be employed for screening the inhibitors of trypsin. The optical nanoprobe was successfully applied for the determination of trypsin in human serum and urine samples with good accuracy and satisfactory recovery.