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In this paper, based on the derivation of the Hecht model and Many model, we establish a new theoretical model and deduce its mathematical equation by considering an even-distributed charged center of certain concentration under constant illumination. This model helps us deeply understand the carrier transport performance of Cd0.9Zn0.1Te (CZT) under various illuminations and non-uniform distribution of the internal electric field in CZT. In our research, direct current photoconductive technology (DCPT) is applied to assess the electrical transport properties of carriers in CZT crystals, which is verified by room temperature Am-241 alpha-particle responses and charge collection efficiency test. The mobility-lifetime product (μτ) for carriers is extracted from fitting the Hecht model by DCPT for CZT radiated from the cathode and anode by a constant laser, respectively. Moreover, the carrier transport properties of CZT under various light intensities and during a wide range of temperatures are also taken and analyzed in detail, which enable us to develop the best performance of CZT. In addition, we figure out a method for estimating μeτe and μhτh on different positions of CZT wafer on the basis of the pixel detector that collects single polarity charge, and several corrective actions have improved the accuracy of the measurement. [ABSTRACT FROM AUTHOR]

A new series of quaternary magnetic Fe80-xCoxP14B6 (x=20, 30, 40, 50, 60 at. %) bulk metallic glasses (BMGs) has been prepared by combining fluxing treatment and J-quenching technique, and the maximum critical diameter for fully glass formation reaches up to 2.0 mm for x=40 among this series of FeCo-based BMGs. The effects of Co content on glass-forming ability, thermal stability, mechanical and magnetic properties of the present FeCo-based BMGs have been systematically investigated. It is found that the highest thermal stability, namely the highest glass transition temperature (Tg) and the onset crystallization temperature (Tx), is achieved when the ratio of Fe and Co contents is 1:1 in the present FeCo-based BMGs. It should be noted that the maximum Curie temperature reaches 791K when x =40, which is the highest Curie temperature for (Fe, Co, Ni)-based BMGs so far as is known. Moreover, the present FeCo-based BMGs exhibit very good soft magnetic properties and large room plasticity, which are promising for potential industrial application as high performance functional and structural materials. [ABSTRACT FROM AUTHOR]

CdMnTe films were prepared on quartz substrates by closed-space sublimation of polycrystalline Cd0.74Mn0.26Te powders. This was performed at different substrate temperatures (Ts=200, 300, 350, and 400 °C). The interfacial adhesion strength between the films and substrates, when fabricated from polycrystalline powders, was greater than that of films grown using a bulk source. X-ray diffraction studies revealed that the as-deposited films had a zinc blende structure with a preferential (111) orientation. Precipitation of Te occurred in the films deposited at Ts=200 C, as confirmed using scanning electron microscopy, x-ray diffraction, and Raman spectroscopy. The growth mode and re-evaporation dependence on the value of Ts of the films were investigated. Our results suggested that materials suitable for radiation detection can be grown from a powder source at lower substrate temperatures then when grown from a bulk source. [ABSTRACT FROM AUTHOR]

A new titanium dioxide (TiO2) slurry formulation is herein reported for the fabrication of TiO2 photoanode for use in dye-sensitized solar cells (DSSCs). The prepared TiO2 photoanode featured a highly uniform mesoporous structure with well-dispersed TiO2 nanoparticles. The energy conversion efficiency of the resulting TiO2 slurrybased DSSC was ~63% higher than that achieved by a DSSC prepared using a commercial TiO2 slurry. Subsequently, the incorporation of acid-treated multi-walled carbon nanotubes (CNTs) into the TiO2 slurry was examined. More specifically, the effect of varying the concentration of the CNTs in this slurry on the performance of the resulting DSSCs was studied. The chemical state of the CNTs-incorporated TiO2 photoanode was investigated by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. A high energy conversion efficiency of 6.23% was obtained at an optimum CNT concentration of ~0.06 wt.%. The obtained efficiency corresponds to a 63% enhancement when compared with that obtained from a DSSC based on a commercial TiO2 slurry. The higher efficiency was attributed to the improvement in the collection and transport of excited electrons in the presence of the CNTs. [ABSTRACT FROM AUTHOR]