Cu2ZnSn(Sx, Se1−x)4 (CZTSSe) material has attracted more and more researchers' attention due to its low cost, environmental protection, high absorption coefficient, and adjustable bandgap. The classic structure of CZTSSe solar cell is Al: ZnO (AZO)/i-ZnO/CdS/CZTSSe, so it is very important to find a suitable buffer layer material to replace the toxic cadmium (Cd). Therefore, the performance of solar cells with different buffer layers is compared. The buffer layer is replaced by the indirect bandgap n-In2S3, which has high stability and light transmittance. And in this work, spectroscopic ellipsometry is used to measure the absorption coefficient spectrum of the absorber layer CZTSSe with different sulfur-to-selenium ratio, and wxAMPS numerical simulation software is used to simulate various material properties and draw conclusions. When X = 0.4, the performance of the CZTSSe TFSC reaches the optimal value.

Recently, reversible data hiding (RDH) based on pixel value order (PVO) has been an important research direction in the field of information security due to its high-fidelity characteristics. However, PVO-based schemes have low embedding capacities (EC) because the pixels whose prediction-error greater than 1 or less than -1 on the histogram just shifted but not selected for embedding data. Dual-image techniques have often been used in recent years. In this paper, we use dual-image to design a new shift strategy that allows secret data to be embedded in those pixels only shifted in PVO-based schemes previously to improve the EC. The number of secret message bits for each embedding is fixed in most dual-image RDH methods, which leads to image redundancy not be fully exploited. In the proposed method, the number of embedded bits changes dynamically according to the predictionerror so that the visual quality of the stego images is better. Experimental results verify that the proposed method is superior to some other state-of-the-art PVO-based and dual-image RDH methods.

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Cu2ZnSnS4 (CZTS) materials have been widely investigated due to their excellent properties in solar cell applications. The common reference structure for CZTS cells is Al:ZnO(AZO)/i-ZnO/CdS/CZTS, but it is critical to find a suitable buffer layer material to replace toxic cadmium (Cd). In addition, the efficiency of CZTS cells is improved by improving the doping type (n or p) and doping concentration of MoS2 generated during the manufacturing process. wxAMPS was used to simulate the performance of a CZTS battery with an Al:ZnO/i-ZnO/Zn(O,S)/CZTS/(MoS2) structure. The performance of batteries using Zn(O,S) and CdS as buffer layers was compared. The optimal thickness of CZTS layer and the doping concentration of CZTS layer were calculated, and the doping type and concentration of MoS2 layer were analyzed and the performance of the battery was improved by optimizing the solar cell parameters. This work provides novel ideas for designing and manufacturing higher performance solar cells.