铋、氧化铋、硫化铋在硝酸-硫脲中的溶解性

研究了铋、氧化铋、硫化铋在硝酸-硫脲中的溶解性。三价铋离子与硫脲溶液可形成黄色络合物,在波长为460nm处,反应温度为25℃,反应时间为6min,硝酸浓度为1.0mol/L,硫脲浓度为0.5mol/L,振荡速率为160r/min条件下铋含量在0.059—4.57μg/mL范围内服从郎伯-比尔定律,检出限为m=0.04μg。铋矿物的溶解性顺序大小为Bi2O3>Bi>Bi₂S₃。本方法操作简便,可靠,实验结果满意,具有广泛的实用意义。     

Enhancement of photosensitivity in bismuth doped Cu2ZnSnS4 thin films

In this paper, the effect of bismuth doping on the structural, morphological, optical and electrical properties of Cu₂ZnSnS₄ (CZTS) films has been investigated. The undoped and bismuth doped CZTS films (0, 0.5, 1, 1.5 and 2 mol%) were deposited on glass substrates by solution based method. The XRD result shows a significant improvement in the crystallinity of the films with increase in bismuth concentration. The Raman spectra of the films show the dominant peak at 334 cm^–1 corresponding to A₁ vibrational mode of CZTS kesterite phase. The FESEM micrographs of the films show an enhancement in the grain size and densification with the addition of bismuth ion concentration. The optical bandgap of the films was found to vary (1.59–1.40 eV) with the doping of bismuth ions. The I –V characteristics indicate twofold increment in the photoconductivity for the bismuth doped CZTS films under 100 mW/cm² illumination suggesting their potential application in photovoltaic devices. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)     

The optical properties of thallium,lead and bismuth in oxide glasses

Absorption, fluorescence, excitation and decay time measurements have been made on a range of glasses containing thallium, lead and bismuth. In calcium phosphate and sodium silicate glasses the bands in both absorption and emission have been assigned to the A band of the Seitz model. For the bismuth doped glasses the A band was always observed in absorption but the emission was very dependent upon glass composition. Configurational coordinate curves have been constructed for Tl⁺ and Pb² in a glass of composition CaO. P₂O₅. Coordinate diagrams are also used to explain the presence or absence of bismuth fluorescence in certain glass compositions. In some borate glasses containing bismuth a brown colouration was observed. This was probably due to particle separation. No A band emission was observed from bismuth in a calcium phosphate glass. Instead there was a faint red emission similar to the cathodoluminescent bands of crystalline calcium phosphates.     

Impedance studies on bismuth-ruthenate-based electrodes

Doped bismuth ruthenates and bismuth ruthenate-stabilized bismuth oxide composites were studied as prospective cathode material for solid oxide fuel cells. Symmetric cells were fabricated on gadolinium-doped ceria electrolytes and studied by electrochemical impedance spectroscopy. Ca- and Ag-doped bismuth ruthenate electrodes (5–10 mol%) showed the same characteristic frequency as undoped bismuth ruthenate but with higher activation energy and slightly better performance above ∼550 °C. At 700 °C, area-specific resistance (ASR) of undoped, 5 mol% Ca and 5 mol% Sr-doped bismuth ruthenate electrode was 1.45, 1.24, and 1.41  Ωcm², respectively. The change in ASR as a function of oxygen partial pressure and current bias suggests that the rate-limiting steps for oxygen reduction in bismuth ruthenate systems are charge transfer and surface diffusion of dissociatively adsorbed oxygen to triple phase boundaries. Introduction of the erbia-stabilized bismuth oxide (ESB) phase reduced both the rate-limiting steps resulting in much improved electrode performance. At 700 °C, composite electrodes containing 31.25–43.75 wt% ESB exhibited an ASR of 0.08–0.11 Ωcm².     

Y_(3-x)Bi_xFe_5O_(12)系列单晶的磁振子劲度系数,散射强度及线宽的布里渊散射研究

Ｙ３－ｘＢｉｘＦｅ５Ｏ１２系列单晶的磁振子劲度系数，散射强度及线宽的布里渊散射研究萧季驹李泽民（香港城市大学物理及材料科学系香港九龙）刘玉龙朱恪张昊（中科院物理研究所北京１０００８０）ＢｒｉｌｏｕｉｎＳｃａｔｅｒｉｎｇＳｔｕｄｙｏｎＥｘｃｈａｎｇｅＳ...     

Optical properties and adhesion of air oxidized vacuum evaporated bismuth thin films

Highly adhesive bismuth oxide thin films on glass have been prepared by air oxidation of vacuum evaporated bismuth thin films at various temperatures. The transmittance, optical band gap, refractive index and adhesion show temperature and oxidation time effects. The films show a direct band gap between 2 and 2.5 eV. The refractive indices are in the range 1.854-1.991. The transmittances of the bismuth oxide films are quite high in a large wavelength range. These bismuth oxide films can have potential use in optical waveguides.     

On the question of Bi(III) complexes in NaCl

The absorption of trivalent bismuth in solutions of sodium chloride of different concentrations was studied. The absorption bands were ascribed to complexes of bismuth with chlorine. The agreement between absorption bands in NaCl and KCl crystals doped with bismuth and in sufficiently concentrated solutions shows that bismuth in these crystals forms an octahedral complex with six neighbouring chlorine ions.     

Nano-scaled top-down of bismuth chalcogenides based on electrochemical lithium intercalation

A two-step method has been used to fabricate nano-particles of layer-structured bismuth chalcogenide compounds, including Bi₂Te₃, Bi₂Se₃, and Bi₂Se_0.3Te_2.7, through a nano-scaled top-down route. In the first step, lithium (Li) atoms are intercalated between the van der Waals bonded quintuple layers of bismuth chalcogenide compounds by controllable electrochemical process inside self-designed lithium ion batteries. And in the second step, the Li intercalated bismuth chalcogenides are subsequently exposed to ethanol, in which process the intercalated Li atoms would explode like atom-scaled bombs to exfoliate original microscaled powder into nano-scaled particles with size around 10 nm. The influence of lithium intercalation speed and amount to three types of bismuth chalcogenide compounds are compared and the optimized intercalation conditions are explored. As to maintain the phase purity of the final nano-particle product, the intercalation lithium amount should be well controlled in Se contained bismuth chalcogenide compounds. Besides, compared with binary bismuth chalcogenide compound, lower lithium intercalation speed should be applied in ternary bismuth chalcogenide compound.     

Drift of bismuth atoms in the laser-radiation field and record of information in thin films of a phthalocyanine dye

We report on the results of experimental studies of the characteristics of record of information by laser radiation in thin films of a phthalocyanine dye with bismuth. It is shown that bismuth atoms drift in dye-bismuth-dye triplex films under the action of nanosecond laser pulses. This effect is due to the electrostatic interaction between the bismuth ions and the spatial-charge field of electrons biased due to photon pressure. __________ Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 49, No. 6, pp. 513–518, June 2006.     

Effect of atmospheric composition on the phase formation in the Ba-Bi-O system

The phase formation in the Ba-Bi-O system is significantly affected by oxygen pressure during its synthesis. The reason for the sensitivity of this system to oxygen pressure consists in mobile coexistence of bismuth ions in different oxidation states in the same oxide (Bi⁵⁺ and Bi³⁺, Bi³⁺ and Bi²⁺, etc.). This circumstance determines the oxide structure type and the ability to formation of structural subtypes, i.e., oxides of an isostructural homologous series. The presence of bismuth ions in different oxidation states in the same oxide determines the variety of properties of both bismuth oxides and complex oxides on their basis (ferroelectric, semiconducting, superconducting, and other properties).     

Propagation of Alfvén waves in bismuth

The present study reports on experimental investigations about the phase velocity diagrams of Alfvén waves in the anisotropic solid-state plasma of bismuth. Alfvén-wave transmission at 34 GHz and 4.2 K has been observed, using an interference technique of high sensitivity. The experimental results are in good agreement with a theoretical model given by Buchsbaum, which makes only use of the anisotropic mass tensor of bismuth.     

Dielectric and relaxation properties of thermally evaporated nanostructured bismuth sulfide thin films

Nanostructured bismuth sulfide thin films were prepared onto glass substrates with particle size of 21 nm by thermal evaporation using readily prepared bismuth sulfide nanocrystallite powder. The X-ray diffraction pattern revealed that bismuth sulfide thin films exhibit orthorhombic structure. The existence of quantum confinement effect was confirmed from the observed band gap energy of 1.86 eV. AC and DC electrical conductivity of Al/BiSnc/Al structures was investigated in the frequency range 0.5-100 kHz at different temperatures (303-463 K) under vacuum. The AC conductivity (σ_ac) is found to be proportional to angular frequency (ω^s). The obtained experimental result of the AC conductivity showed that the correlated barrier hopping model is the appropriate mechanism for the electron transport in the nanostructured bismuth sulfide thin films. DC conduction mechanism in these films was studied and possible conduction mechanism in the bismuth sulfide thin films was discussed.     

阳离子金黄铋染料的合成及其光谱研究

本文以阳离子金黄和硝酸铋为原料合成了阳离子金黄铋染料,并对产物进行了铋含量的测定,测定了产物的可见光吸收光谱,红外光谱。     

活性艳蓝铋染料的合成及其光谱研究

本文以活性艳蓝和硝酸铋为原料，合成了活性艳蓝铋染料。对产物进行了铋含量的测定，测定了产物的可见光吸收光谱、红外光谱。     

Characterisation of thin films of bismuth oxide by X-ray photoelectron spectroscopy

The XPS (or ESCA) technique has been used for the characterisation of vacuum-deposited thin films of bismuth oxide. The spectra of Bi metal and Bi₂O₃ powder are used for comparison. The characterisation is carried out by consideration of the positions of the Bi 4f_{$\text{7}\text{2}$} and 4f_{$\text{5}\text{2}$} peaks and by using peak-fitting routines. A lower suboxide of bismuth, and metallic bismuth are observed in bismuth oxide films as evaporated. Oxidation of these films by heating in air results in bismuth(III) oxide. A linear relation is found between the binding energies and oxidation state. The corresponding O 1s spectra for the two types of film are also discussed.     

Coherent phonon excitation in bismuth

Ultrafast time-resolved reflectivity of a bismuth thin film evaporated on a silicon substrate is measured to investigate coherent phonons in bismuth. The reflectivity result is analyzed by a linear chirp approximation to obtain the time dependent frequencies of coherent phonons. Not only the optical modes are detected, which are generated by a combination of impulsive stimulated Raman scattering and displacive excitation of coherent phonon, acoustic phonon modes are also observed, which are emitted by the A_1g optical phonon.     

Equations of state and shock-induced transformations in solid I-solid II-liquid bismuth

An equation of state is determined for each phase in the solid I-solid II-liquid region of bismuth. Equality of the Gibbs free energy for each pair of phases determines the phase boundaries and triple point in the temperature-pressure plane. From the complete equation of state, the shock-wave response of bismuth preheated to 493 °K. is calculated and comparison is made with experimental data obtained by means of quartz transducer instrumentation. These results suggest that bismuth undergoes a certain degree of melting on the microsecond time scale of the shock-wave experiment. This is contrary to previous results and conclusions drawn from data on the shock-wave propagation in bismuth. These seemingly contradictory results may be due to microstructural differences in the samples or to differences in measuring techniques.     

Bismuth onion thin film in situ grown on silicon wafer synthesized through a hydrothermal approach

Bismuth onion structured nanospheres with the same structure as carbon onions have been synthesized and observed. The nanospheres were synthesized through a hydrothermal method using bismuth hydroxide and silicon wafer as reactants. By controlling the heating temperature, heating time, and the pressure, nanoscale bismuth spheres can be in situ synthesized on silicon wafer, and forms a bismuth onion film on the substrate. The electronic property of the films was investigated. A formation mechanism of the formation of bismuth onions and the onion film has been proposed on the basis of experimental observations.     

Electrons in bismuth

A review of the electronic properties of pure bismuth is given. Theoretical ideas on the band structure of bismuth and the dispersion relation for electrons near the bottom of the conduction band are briefly outlined. The experiments considered are those which give the most precise information on the Fermi surface (quantum effects in conductivity, cyclotron resonance, size effects, magnetoplasma waves, etc.) and on the electron energy spectrum near the bottom of the conduction band (studies in the quantum limit, infra-red magneto-reflection). The validity of the Cohen model as a first approximation to the electron spectrum in bismuth is established, and deviations from this model are described. Experiments are proposed which may give additional information on electrons in bismuth.