In this paper, a n-i-p planar heterojunction simulation of Sn-based iodide perovskite solar cell (PSC) is proposed. The solar cell structure consists of a Fluorine-doped tin oxide (FTO) substrate on which titanium oxide (TiO2) is placed; this material will act as an electron transporting layer (ETL); then, we have the tin perovskite CH3NH3SnI3 (MASnI3) which is the absorber layer and next a copper zinc and tin sulfide (CZTS) that will have the function of a hole transporting layer (HTL). This material is used due to its simple synthesis process and band tuning, in addition to presenting good electrical properties and stability; it is also a low-cost and non-toxic inorganic material. Finally, gold (Au) is placed as a back contact. The lead-free perovskite solar cell was simulated using a Solar Cell Capacitance Simulator (SCAPS-1D). The simulations were performed under AM 1.5G light illumination and focused on getting the best efficiency of the solar cell proposed. The thickness of MASnI3 and CZTS, band gap of CZTS, operating temperature in the range between 250 K and 350 K, acceptor concentration and defect density of absorber layer were the parameters optimized in the solar cell device. The simulation results indicate that absorber thicknesses of 500 nm and 300 nm for CZTS are appropriate for the solar cell. Further, when optimum values of the acceptor density (NA) and defect density (Nt), 1016 cm−3 and 1014 cm−3, respectively, were used, the best electrical values were obtained: Jsc of 31.66 mA/cm2, Voc of 0.96 V, FF of 67% and PCE of 20.28%. Due to the enhanced performance parameters, the structure of the device could be used in applications for a solar energy harvesting system.

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The content of biogenic amines has been studied due to the toxicity of these compounds in humans when are consumed exogenously, and is used as an indicator of quality in the food industry. The manly method for its determination is high performance liquid chromatography. However, it requires a long time for analysis. An alternative method is the use of biosensors, porous silicon with gold nanoparticles were obtained by electrochemical attack assisted with metal salt. These substrates were used for the construction of a biosensor capable of detecting BA using diamine oxidase enzyme as an element of biological recognition and is binding using the self-assembled monolayers method. The correlation between scanning electron microscopy, X-ray dispersive energy spectroscopy, and Fourier Transform infrared spectroscopy analysis, demonstrated the correct construction of the biosensor and the detection of biogenic amines by interaction with the enzyme. Finally, with the built biosensor it was possible to detect three important biogenic amines found in food.

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