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Inorganic Bi-based double perovskite oxide, Bi2FeCrO6 (BFCO), has offered new opportunities for applications in burgeoning fields of optoelectronic and photovoltaic, due to its unique multiferroic properties at room temperature. The P-type direct-bandgap semiconductor Cu2ZnSnS4 (CZTS) was adopted to couple with BFCO as hole transport layer, in order to construct BFCO/CZTS heterostructure. Pulsed laser deposition (PLD) technique was used to deposit above-mentioned polynary compound films on different substrates (i.e. FTO conductive glass, Nb-doped SrTiO3 and Si/SiO2/Ti/Pt). For the preparation of heterojunctions, the interfacial defects and impurities could be effectively restrained by in-situ layer-by-layer deposition technique. The systematical analysis according to SEM, AFM, EDS and XRD measurements verified that the morphology of the achieved stoichiometric films was basically uniform and dense. The impacts of deposition temperature on the product performance were emphatically investigated. The bandgap of obtained BFCO and CZTS films (i.e. 2.23 eV and 1.49 eV, respectively) was estimated by using Tauc method based on visible absorption spectroscopy measurements. The results show that BFCO/CZTS heterojunction has a favorable rectifying characteristic; the leakage current mechanism is consistent with Schottky emission model when the electric field intensity spans from 0.5 kV/cm to 2.0 kV/cm.

The "octahedral structure model" is introduced for three-dimensional reticulated porous materials, as well as the mathematical relations of their basic physical and mechanical properties. On this basis, the verification works about some performance relations, including the conductivity and tension, etc, are reviewed in this paper. A number of issues were discussed with the emphases on the practicality of these mathematical and physical relations, the rationality of the correction coefficients, the significant influence on the calculation results, and the allowable stress and the plastic index value of the corresponding dense body were also analyzed in details. According to this mathematical and physical relationship, the performance indexes such as the electrical resistivity of porous products can be calculated by the easily measurable basic parameters like the porosity. The experimental results prove this way feasible. Therefore, this method can be superior to the finite element and other complex computational methods.