Broadband photodetector of high quality Sb2S3 nanowire grown by chemical vapor deposition

Low dimensional semiconductors can be used for various electronic and optoelectronic devices because of their unique structure and property.In this work,one-dimensional Sb2S3 nanowires(NWs)with high crystallinity were grown via chemical vapor deposition(CVD)technique on SiO2/Si substrates.The Sb2S 3 NWs exhibited needle-like structures with inclined cross-sections.The lengths of Sb2S3 nanowires changed from 7 to 13 pm.The photodetection properties of Sb2S3 nanowires were comprehensively and systematically characterized.The Sb2S3 photodetectors show a broadband photoresponse ranging from ultraviolet(360 nm)to near-infrared(785 nm).An excellent specific detectivity of 2.1×1014 Jones,high external quantum efficiency of 1.5×104％,sensitivity of 2.2×104 cm2W-1 and short response time of less than 100 ms was achieved for the Sb2S3 NW photodetectors.Moreover,the Sb2S3 NWs showed out-standing switch cycling stability that was beneficial to the practical applications.The high-quality Sb2S3 nanowires fabricated by CVD have great application potential in semiconductor and optoelectronic fields.     

Mg含量对Mg3(1+z)Sb2化合物热电传输性能的影响

Mg₃Sb₂化合物具有良好的热电性能和成本优势, 受到研究者的广泛关注。由于Mg元素具有很高的饱和蒸汽压和化学反应活性, 因此Mg₃Sb₂在合成过程中含量难以精确控制。本研究利用固相反应/球磨结合放电等离子体烧结制备了不同Mg含量的Mg_3(1+z)Sb₂(z=0, 0.02, 0.04, 0.06和0.08)样品, 通过物相结构分析和热电性能测试, 研究了Mg含量对Mg₃Sb₂化合物热电性能的影响规律。结果表明, 随着名义Mg含量的增加, 实际Mg含量在Mg₃Sb₂化合物中由缺失状态转变为过量状态, Mg_3(1+z)Sb₂(z=0, 0.02, 0.04)样品存在Mg空位(${{\text{{V}'}}_{\text{Mg}}}$), 表现为p型传导; 而Mg_3(1+z)Sb₂ (z=0.06, 0.08)样品中存在间隙Mg($\text{Mg}_{\text{i}}^{\centerdot \centerdot }$), 表现为n型传导。Mg_3(1+0.04)Sb₂样品在较宽温区(室温至770 K)内保持最高的热电优值, 该样品最接近本征p型Mg₃Sb₂化合物的组成和热电性能。本研究表明, Mg含量对Mg_3(1+z)Sb₂化合物载流子类型和浓度以及迁移率具有一定的调控作用。     

Breaking the Minimum Limit of Thermal Conductivity of Mg3Sb2 Thermoelectric Mediated by Chemical Alloying Induced Lattice Instability

Thermal properties strongly affect the applications of functional materials, such as thermal management, thermal barrier coatings, and thermoelectrics. Thermoelectric (TE) materials must have a low lattice thermal conductivity to maintain a temperature gradient to generate the voltage. Traditional strategies for minimizing the lattice thermal conductivity mainly rely on introduced multiscale defects to suppress the propagation of phonons. Here, the origin of the anomalously low lattice thermal conductivity is uncovered in Cd-alloyed Mg₃Sb₂ Zintl compounds through complementary bonding analysis. First, the weakened chemical bonds and the lattice instability induced by the antibonding states of 5p-4d levels between Sb and Cd triggered giant anharmonicity and consequently increased the phonon scattering. Moreover, the bond heterogeneity also augmented Umklapp phonon scatterings. Second, the weakened bonds and heavy element alloying softened the phonon mode and significantly decreased the group velocity. Thus, an ultralow lattice thermal conductivity of ≈0.33 W m⁻¹ K⁻¹ at 773 K is obtained, which is even lower than the predicated minimum value. Eventually, Na_0.01Mg_1.7Cd_1.25Sb₂ displays a high ZT of ≈0.76 at 773 K, competitive with most of the reported values. Based on the complementary bonding analysis, the work provides new means to control thermal transport properties through balancing the lattice stability and instability.     

溶胶凝胶法制备掺杂锑（Sb）的透明导电膜

采用溶胶－凝胶方法制备了SnO2掺杂Sb的透明导电膜（简称ATO膜），并讨论了掺杂量和热处理条件对膜可见光透过率及膜电阻率的影响，用XRD，SEM，TG－DTA以及IR等研究了所得薄膜的结构性质，制备出导电性能优良的透明导电膜。     

Thermodynamic assessments of the Er–Sb and Sb–Tm systems

By using the calculation of phase diagrams (CALPHAD) method, thermodynamic assessments of the Er–Sb and Sb–Tm systems were carried out based on the available experimental data including thermodynamic properties and phase equilibria. The Gibbs free energies of the liquid, hcp, and rhombohedral phases in the Er–Sb and Sb–Tm systems were modeled by the substitutional solution model with the Redlich–Kister formula, and the intermetallic compounds (Er₅Sb₃, αErSb, βErSb, ErSb₂, Sb₂Tm, αSbTm, βSbTm, α Sb₃Tm₅, and β Sb₃Tm₅ phases) in these two binary systems were described by the sublattice model. An agreement between the present calculated results and experimental data was obtained.     

Sb掺杂对0.95MgTiO3-0.05CaTiO3陶瓷介电性能的影响

采用固相反应法制备了( Mg0.95-X Ca0.05 SbX) TiO3微波介质陶瓷.研究了Sb掺杂对0.95MgTiO3-0.05 CaTiO3 (95MCT)陶瓷性能的影响.结果表明:Sb掺杂95MCT陶瓷的主晶相为MgTiO3和CaTiO3两相,有中间相MgTi2O5的产生;Sb掺杂能有效的降低95 MCT陶瓷...     

钙钛矿锰氧化物La_(0.9)Sb_(0.1)MnO_3电子自旋共振谱的研究

制备了电子掺杂钙钛矿锰氧化物庞磁电阻材料La0.9Sb0.1MnO3,并在不同温度测量了La0.9Sb0.1MnO3的电子自旋共振谱.观察到La0.9Sb0.1MnO3体系存在相分离现象,实验证明,这种电子掺杂的锰氧化物具有复杂的磁结构,随温度升高样品逐渐由铁磁态向顺磁态转变,在220～260K的过渡温区,样品的磁状态最复杂,存在铁磁、顺磁多个磁相共存的现象.通过分解电子自旋共振的积分吸收谱,分析了La0.9Sb0.1MnO3样品磁性随温度的演变过程,并讨论了电子掺杂锰氧化物的磁不均匀性和相分离现象.     

Cr/V/Sb mixed oxide catalysts for the ammoxidation of propane to acrylonitrile: Part I: Nature of the V species

Rutile-type Cr/V/Sb mixed oxides, catalysts for the ammoxidation of propane to acrylonitrile, were prepared and characterized. For atomic ratios between components equal to Cr/V/Sb 1/x/1 and 1/x/2 the systems were monophasic, but different types of compounds formed depending on the ratio between the three metals. The compositional parameter which most affected the nature of the compound formed was the (Cr+V)/Sb atomic ratio. When this ratio was between 2 and ≈1, a rutile Cr³⁺/V⁴⁺/Sb⁵⁺ mixed oxide of composition Cr₁V_xSb₁O_4+2x developed (0<x<1), which in practice corresponds to a solid solution between 1 CrSbO₄ and x VO₂. When the (Cr+V)/Sb ratio was between 0.5 and ≈1, a rutile Cr³⁺/V³⁺/Sb³⁺/Sb⁵⁺ mixed oxide of composition CrV_xSb_1+x+2zO_4+4x+4z developed (0<x<1), which corresponds to a solid solution between 1 Cr³⁺Sb_z³⁺Sb_1+z⁵⁺O_4+4z and x VSbO₄. The distinction between the two classes of compounds was not clear-cut, and when the (Cr+V)/Sb atomic ratio was around 1, mixed oxides containing both V³⁺ and V⁴⁺ formed. Values of the (Cr+V)/Sb atomic ratio lower than ≈0.5 led to the additional formation of antimony oxide.     

Sb掺杂对ZnO厚膜的电导和气敏性能的影响

用共沉淀的方法,制备了纤锌矿结构的ZnO及其掺Sb的ZnO纳米粉.X射线衍射(XRD)分析表明,当锑掺量小于5wt%时没有新相生成.纯ZnO和掺Sb的ZnO器件的气敏和电阻测试结果发现:不同的厚膜烧结工艺对气体的敏感性影响较大,并且掺Sb后ZnO的气敏性能有所提高,电导峰消失.从缺陷角度、XPS分析的结果进行了讨论,初步解释了锑的掺入导致电导变化和气敏性能提高的原因.     

表面活性剂对纳米Sb2O3和纳米 Sb2O3/云母分散性的影响

以片状云母作为微反应器制备了纳米Sb2O3／云母复合物，并用XRD、TEM进行了表征．研究了表面活性剂对纳米Sb2O3颗粒、纳米Sb2O3／云母复合物的粒子性能及粒度分布的影响，并对二者进行了比较．结果表明：纳米Sb2O3被十六烷基三甲基溴化铵处理后，在云母层间均匀生长，形成的纳米Sb2O3分散性好，粒度分布窄．平均粒径约为5nm，比不加云母制备的纳米Sb2O3小30nm．