• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.661-664
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• 2013

• Bulletin of the Korean Chemical Society
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• v.28 no.11
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• pp.1973-1979
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• 2007

Novel organic dyes, JK-34, JK-35 and JK-36 containing bis-dimethylfluorenyl amino coumarin unit are designed and synthesized. Nanocrystalline TiO2 dye-sensitized solar cells were fabricated using these dyes. Under standard global AM 1.5 solar condition, the JK-34 sensitized cell gave a short circuit photocurrent density of 10.05 mA cm?2, open circuit voltage of 0.65 V, and a fill factor of 0.68, corresponding to an overall conversion efficiency η of 4.54%. We found that the power conversion efficiency was shown to be quite sensitive to the structural modifications of bridging thiophene moiety.

• Bulletin of the Korean Chemical Society
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• v.34 no.3
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• pp.713-714
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• 2013

• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2835-2838
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• 2013

• Bulletin of the Korean Chemical Society
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• v.28 no.6
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• pp.953-958
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• 2007

Anchoring quantum dots (QDs) onto thermodynamically stable, large band gap oxide semiconductors is a very important strategy to enhance their quantum yields for solar energy conversion in both visible and near-IR regions. We describe a general procedure for anchoring a few chalcogenide QDs onto the titanium oxide layer. To anchor the colloidal QDs onto a mesoporous TiO2 layer, linker molecules containing both carboxylate and thiol functional groups were initially attached to TiO2 layers and subsequently used to capture dispersed QDs with the thiol group. Employing the procedure, we exploited cadmium selenide (CdSe) and cadmium telluride (CdTe) quantum dots (QDs) as inorganic sensitizers for a large band gap TiO2 layer of dye-sensitized solar cells (DSSCs). Their attachment was confirmed by naked eyes, absorption spectra, and photovoltaic effects. A few QD-TiO2 systems thus obtained have been characterized for photoelectrochemical solar energy conversion.

• Bulletin of the Korean Chemical Society
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• v.32 no.6
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• pp.2083-2086
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• 2011

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2871-2872
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• 2009

• Solar Energy
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• v.10 no.2
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• pp.18-27
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• 1990

The hot water producer by the combination of the solar thermal energy and freon gas compression heat has been developed. Freon R-12 gas was circulated through the system including the solar absorption panel, which has no glassing and no insulation, and the frozen and burst problems were intrinsically eliminated. The manufacturing and running costs may go further down than the regular solar hot water systems.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.387.2-387.2
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• 2016

Glass texturing is a sufficient method for changing the surface morphology to enhance the light trapping. In this study, glass texturing was applied to the perovskite solar cell for improving the current density. Glass substrates (back-side glass of FTO coated glass substrate) were textured by randomly structure assisted wet etching process using diluted HF solution at a constant concentration of etchants (HF:H2O=1:1). Then, the light trapping properties of suitable films were controlled over a wide range by varying the etching time (1, 2, 3, 4 and 5 min.). The surface texturing changed the reflected light in an angle that it can be reflected by substrate glass surface. As a result, Current density and cell efficiency were affected by light trapping layer using glass texturing method in perovskite solar cells.

• Rapid Communication in Photoscience
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• v.4 no.4
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• pp.79-81
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• 2015

The influence of the grain size of the $CH_3NH_3PbI_3$ on the solar cell performance is investigated by controlling the ratio between $CH_3NH_3I$ and $PbI_2$ precursors. As the concentration of the precursors increased from 1.0M to 2.0M, the $CH_3NH_3PbI_3$ grain size increased from ~100nm to ~400nm. The solar cell utilizing the $CH_3NH_3PbI_3$ with large grain size shows improved photocurrent compared to the solar cell utilizing $CH_3NH_3PbI_3$ with small grain size, which is ascribed to the reduced recombination at the boundaries of grains.