Impedance and dielectric analysis of polycrystalline undoped and Fe doped SnS2

Polycrystalline Sn_1−xFe_xS₂ samples with (x=0, 0.125, 0.250 and 0.375) have been prepared by the molten salt solid state reaction method. The X-ray diffraction (XRD) shows that all the samples crystallize in the hexagonal structure, with P-3m1 space group in preferred orientation of (011). The electrical properties have been studied by complex impedance spectroscopy over the frequency range (20 Hz up to 1 MHz) at room temperature. The Nyquist plot for all samples have been fitted using ZMAN software. The impedance analysis showed that all samples exhibit both bulk and grain boundary contributions and it was found that by increasing the iron content, the resistance increases, but, the dielectric constant and dielectric loss tangent decrease which leads to decrease in conduction. The absorption coefficient (α) has been calculated from the complex dielectric constant. Interestingly, there was a significant correlation between the electromagnetic wave absorption and the reduction in the peak intensity of the XRD patterns indicating that when the iron content increases the sample seems to be a good absorber of electromagnetic waves.     

Microstructural study of SnO2 thin layers deposited on sapphire by sol-gel dip-coating

Tin oxide (SnO₂) films have been grown onto (006) sapphire substrates by sol-gel dip-coating using tin alkoxide solutions. It is shown, using grazing-incidence X-ray diffraction, reciprocal space mapping and atomic force microscopy, that thermal annealing at 500 °C induces the crystallization of SnO₂ in the rutile-type phase. Further annealing treatments at temperatures lower than 1100 °C give rise to slow grain growth controlled by surface diffusion, whereas rapid grain growth (controlled by an evaporation-condensation mechanism) takes place at temperatures higher than 1100 °C. Concomitantly, the film splits into isolated islands and a fibre texture occurs at higher temperatures.     

Soldering of solution-processed organic vertical transistor and light-emitting diode on separate glass substrates by tin micro-balls

The vertical organic space-charge-limited transistor made of P3HT and small-molecule phosphorescent organic light-emitting diode (OLED) are made on two separate glass substrate by blade coating, then soldered vertically together by tin balls with 40 μm diameter. The soldering is done by hot wind of 150 °C for 5 min Contact resistance is only 10 Ω. The vertical transistor is annealed at 150 °C for 5 min before soldering to enhance the output current up to 25 mA/cm² and give high thermal stability. Both OLED and the annealed vertical transistor are not affected by the soldering process. The vertical transistor has 1/4 of the OLED area and turns on the bottom-emission white OLED up to 300 cd/m² and orange OLED up to 600 cd/m². The entire operation is within 8 V. OLED and transistor array can therefore be made on separate glass substrates then soldered together to form the display.     

镀锡钢丝锡层厚度的测定

介绍利用原电池及失重法相结合测定镀锡钢丝的镀层厚度的方法。     

Natural honey and black radish juice as tin corrosion inhibitors

The influence of natural honey (chestnut and acacia) and natural honey with black radish juice, on corrosion of tin in aqueous and sodium chloride solutions was studied using weight loss and polarization techniques. The inhibition efficiency of acacia honey was lower than that of chestnut honey, while the addition of black radish juice increased the inhibition efficiency of both honey varieties. The process of inhibition was attributed to the formation of multilayer adsorbed film on the tin surface. The adsorption of natural honey and honey with black radish on tin was found to follow the Langmuir adsorption isotherm.     

n-Si/SnO2 junctions based on macroporous silicon for photoconversion

For the first time it is demonstrated that a photovoltaic junction can be formed by spraying a thin, transparent, conductive SnO₂ layer onto macroporous n-type silicon produced by photoelectrochemical etching. With a macropore density of 10⁷ cm⁻², and an average pore diameter in the range 1–2 μm, the cell reflectivity spectrum is flat and drops to a few percent in the visible and near infrared spectral range. EDX analysis and impedance measurements show that charge separation and current collection occur in the upper part of the pores and in the interpore region, whereas the bottom of the pores only acts as a photon absorber. The active junction area is found to be four times larger than with a mirror-polished substrate. A solar cell equipped with just a front ring contact was realized, which attains a solar conversion efficiency of 10% under AM 1.5 conditions.     

The effect of CoSn/CoSn2 phase ratio on the electrochemical behaviour of Sn40Co40C20 ternary alloy electrodes in lithium cells

Samples of a SnCoC-based electrodes, all having the molar composition Sn₄₀Co₄₀C₂₀, but differing by the high energy ball milling synthesis conditions, have been tested in lithium cells. The investigation was carried out by using a series of complementary techniques, including potentiodynamic cycling with galvanostatic acceleration, galvanostatic charge–discharge cycling and impedance spectroscopy. The results confirmed the high capacity delivery of this type of ternary electrodes but also revealed that their electrochemical behaviour is influenced by the relative abundance of the nanosized domains of CoSn and CoSn₂ in their structure.     

原子吸收法测定银铜锌锡合金和铜合金中的锡

用浓硝酸和浓硫酸溶样，以空气－乙炔火焰原子吸收法测定银铜锌锡合金和铜合金中的锡，测定范围为０．０２％￣１０．１２％。     

Fabrication of tin oxide film by sol–gel method for photovoltaic solar cell system

Transparent conducting tin(IV) oxide thin films have been developed with a sol–gel method, which is a low-cost process for the electrode materials of solar cell substrate. The precursor solution was made of tin isopropoxide dissolved in isopropyl alcohol. The hydrolysis rate was controlled by the addition of triethanolamine. Dipping and spin-coating technique were applied to coat tin oxide on borosilicate glass. The resistivity of the thin film was lower than 0.01 Ω-cm and the transmittance was higher than 90% in a visible range.