Impacts of additions of rare earth oxides during the flux treatment of a commercial SrTiO3 powder on activity of photocatalysts based on these flux-treated SrTiO3 for overall water splitting were investigated. Appreciable improvements of photocatalytic activities were achieved for the SrTiO3 samples added with Sc₂O₃; the other oxides (La2O3 and Y2O3) were detrimental. Structural analyses suggested that the Sc3+ cation is a preferable dopant than that of the known dopant of Al3+ in view of the quantitative control in the majority carrier (e−) concentration.

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Intermediate band solar cells are expected to surpass the efficiency limit of conventional single-junction solar cells. We fabricated an GaSb/GaAs quantum ring intermediate band solar cell integrated with a light trapping structure which showed an increased light absorption and a higher material quality with reduced non-radiative recombination.

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In this study, we investigated the effects of heat treatment in atmosphere followed by sulfurization of back contact metal Mo on J−V characteristics. It is found that the sulfurization of MoOx contributes to the improvement of open circuit voltage of CZTS formed on the treated SLG/Mo. As a result, energy conversion efficiency is enhanced.

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The influence of post-annealing for CBD-Zn(O,S)/SnS structures was investigated. Moreover, the Zn(O,S)/SnS energy band alignment and photoluminescence properties were investigated as a function of the annealing temperature. The conduction band offset in the Zn(O,S)/SnS structure was -0.1 to +0.7 eV, depending on the annealing temperature.

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The effect of sputtering gas condition for tin monosulfuide (SnS) deposition was investigated. SnS was deposited via RF reactive sputtering by using mixed N2･H2･Ar gas under the p(N2) = 33%–50% condition in order to obtain N-doped thin films. The formation of nitride materials, such as tin pernitride (SnN2), was realized during SnS thin film deposition with excess N2 supply.

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Tin dioxide (SnO2) thin film was deposited on transparent flexible polyimides (PIs) via RF magnetron sputtering. The CO2 sensor for detection at room temperature was fabricated using the SnO2 film. The sensitivity of the sensor on the PI substrate increased when the SnO2 deposition temperature was increased. Moreover, SnO2 thin film was transferred onto flexible dimethylpolysiloxane substrate by dissolving the NaCl sacrificial layer.

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