We have fabricated Cu2SnS3(CTS) thermoelectric (TE) legs with electrodes. Consequently, Al is found to be the most suitable electrode material for the CTS TE legs fabricated by the monobloc sintering among Al, Mo, W, Cu, Sn, Zn and Ag. An intermediate layer consisted of CuS and/or Al/CTS is found to be effective to reduce the contact resistance (CR). The CR of less than 10-1 cm2 can be obtained.

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The effects of controlling the surface layer of Cu(In, Ga)Se2 (CIGS) photoelectrodes through annealing in various atmospheres on water splitting were investigated. The photocurrent density of the CIGS photoelectrode increased when annealed in O2, whereas the photocurrent density and onset potential decreased when annealed in a vacuum. These results suggest that the annealing process for the CIGS layer in different atmospheres influenced the surface layer of the CIGS photoelectrodes, affecting the photocurrent density and onset potential.

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Cu3BiS3 powders were synthesized by a polyol method, and their microstructures were analyzed. Changes in the lattice constants, crystallite size, strain, dislocation density, grain size and relative composition of the Cu3BiS3 due to the synthesis temperature were observed.

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Cu2ZnSnS4 (CZTS) single crystal is a high-performance thermoelectric material while using environmentally friendly materials. In this study, we investigated the impact of grain-boundary on thermal conductivity and the improvement of conversion efficiency in CZTS by the combination of experimental and theoretical results.

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This study aims to form CZTS film on stainless steel. We focus the SUS304 as a bottom electrode and the substrate because Mo-coated substrates have been used for polycrystalline thin film solar cells. Samples were analyzed by X-ray diffraction, SEM and EDS. It was confirmed that CZTS could be formed on SUS304.These results suggest that CZTS on stainless steel has the potential for realizing sustainable polycrystalline thin film solar cells.

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In this study, the photovoltaic properties of Cu₂SnS₃ (CTS) solar cells were evaluated by varying the amount of potassium fluoride (KF) added to the films. KF deposition was used to improve the photovoltaic properties of the CTS solar cells as compared with alkali metal-free films. The best photovoltaic properties were obtained for the thin film in which 40 mg of KF was evaporated.

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Cu2SnS3(CTS) thin films were prepared by sol-gel dip-coating method under non-vacuum conditions. Crystallinity was improved by adding Na, while rapid cooling from 400℃ to Room Temperature did now show significant effect. In the future, CTS thin films will be studied by changing the take-out temperature to investigate the effects of rapid cooling.

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LaOCl was added to SnO2 thin films at various La concentrations to improve the sensitivity of a visible light transmissive CO2 sensor. XRD patterns confirmed the addition of LaOCl, and the gas sensitivity increased with increasing La concentration. However, transmission measurements confirmed that excessive addition significantly reduced transmittance in the visible light region.

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The NiO thin film was deposited using electrostatic spray deposition (ESD). Increasing the weight ratio of water in the solvent promoted the crystal growth of NiO. It is assumed that water serves as the oxygen source in the deposition of the NiO film using ESD. This result marks the first step in investigating the growth mechanism of NiO using ESD.

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Multilayered films of ZnS and ZnSe were prepared by spray-assisted layer-by-layer assembly. The thickness and optical constants of the fabricated thin films were analyzed by spectroscopic ellipsometry. The results showed that homogeneous nanoparticle multilayer films can be formed using the spray assisted method as well as the dipping method.

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In this study, p-type transparent semiconductor materials CuCl1-xIx(copper halide-based materials) were prepared by using wet process of sol-gel dip-coating method. Crystallinity on thin films is anticipated to be improved by annealing treatment. The thin films were evaluated using XRD, SEM, transmission, and reflection analyses. The results show that an annealing temperature of 180°C is optimal for film deposition.

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We focused on the pseudo-cubic crystal structure of the chalcopyrite compound ZnSnAs2. The crystal growth conditions of ZnSnAs2, which is expected to have a high power factor due to its structural symmetry, was investigated and its thermoelectric properties were evaluated.

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The light-induced deformation phenomenon observed in ternary thallium compounds can induce local deformation depending on the position of the light spot. This characteristic suggests that the optical constants can also be spatially controlled by changing the shape of the pump light. This study used an imaging Mueller matrix ellipsometer to investigate the relationship between the pump light spot shape and optical constant changes.

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