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In this study, we developed a new facial recognition system using thin-film solar cells as sensors. When the face of a user is illuminated by LED lights on the left and right sides of the system and the reflected light enters the cells at the corresponding positions, differences in facial skin colors and 3D contours lead to different output voltages and currents of the thin-film solar cells. This is the basis of facial feature identification. We found that the accuracy of thin-film-solar-cell-based facial recognition can be improved by precisely controlling changes in LED light intensity. The facial features of six different users were successfully distinguished by this method, thus verifying that thin-film solar cells can be used for green power generation, as well as for facial recognition.

This study proposes a method for recycling and activating the titanium oxide (TiO2)/fluorine-doped tin oxide (FTO) photoanode in dye-sensitized solar cells (DSCs) by repeated dye adsorption and desorption processes using various desorption agents. This simple and convenient method could be utilized to activate TiO2 photoelectrodes for DSCs after the long-term operation. The devices are immersed in acidic, alkaline, and neutral media of various concentrations for desorption and then are soaked in the N719 solution again. The optimal device had an overall power conversion efficiency (AM 1.5 G, 100 mW/cm2) with 5 × 10−3 M NaOH solution as a desorption agent being 6.44% better than that of devices that had not undergone recycling and activation.

A diffusive solar cell window comprises a diffusion plate with TiO2 nanoparticles sandwiched between two glass layers. It is a simple, inexpensive, easy-to-made, and highly reliable transparent solar energy module. To improve its power generation efficiency as well as maintain indoor natural lighting, we examined the scattering mechanism in the diffusion plate with TiO2 nanoparticles within a diffusive solar cell window by Mie scattering simulations. In this work, a multiwavelength ASAP ray tracing model for a diffusive solar cell window with acceptable accuracy was developed to investigate the influence of the diffusion plate design parameter, mainly concentration of a diffusion plate with determined particle size distribution, on power generation efficiency and color shift of transmitted sun light. A concept of “effective average radius” was proposed to account for the equivalent scattering effect of a size distribution of quasispherical particles. Simulation results demonstrated that both the transmitted light and its correlated color temperature decreased as the concentration increased for a large-size diffusive solar cell window. However, there existed a maximum power generation efficiency at around 160 ppm concentration. The optimal design for a large-size diffusion plate inside a diffusive solar cell window by taking indoor lighting into account was suggested based on the simulation results.

An examination is done on the extended Cauchy equations, which are derived, based on the Vuks equation for describing the wavelength- temperature-dependent refractive indices of liquid crystal compounds and mixtures. In conclusion, correlations between the Cauchy coefficients for the nematic and isotropic phases are derived and validated by the experiments.

Research is done on thermally driven transport and exchange of hydrogen and deuterium in silicon-based metal-oxide-semiconductor (MOS) device-related structures, which were experimentally, examined using elastic recoil detection analysis. In conclusion, isotope exchange in the polycrystalline Si/SiO2 structure was noticed above 450 degrees C, BPSG revealed very little relative isotope exchange and implications to MOS device processing is examined.

An examination is done of anisotropic optical properties of vacuum-deposited thin films of high-efficiency blue-emitting ter(9,9-diarylfluorene)s using variable-angle spectroscopic ellipsometry. It is inferred that the vacuum-deposited ter(9,9-diarylfluorene) molecules tend to align their molecular axes and pi-pi* transition dipole moments along the substrate surface as noticed in spin-coated films of alkyl-substituted polyfluorenes or oligofluorenes, even though the present ter (9,9-diarylfluorene)s have rigid and bulky aryl substituents on C9, relatively shorter oligomer chains, and very different deposition conditions.

The carrier-transport properties of amorphous ter(9,9-diarylfluorene)s are reported. The unusual nondispersive ambipolar carrier transport and high electron mobility is observed for these molecular materials.

A convergent synthesis, the single-crystal structure and intriguing properties of novel ter(9,9-dairylfluorene)s are reported. Ter(9,9-diarylfluorene)s that contains intrinsically stronger Csp(super 3) -Csp(super 2) bonds between the pendant aryl groups and the C9 carbon of fluorene exhibit excellent morphological and thermal stability.

This study proposes a method for recycling and activating the titanium oxide (TiO2)/fluorine-dopedtin oxide (FTO) photoanode in dye-sensitized solar cells (DSCs) by repeated dye adsorption and desorption processes using various desorption agents. This simple and convenient method could be utilized to activate TiO2 photoelectrodes for DSCs after the long-term operation. The devices are immersed in acidic, alkaline, and neutral media of various concentrations for desorption and then are soaked in the N719 solution again. The optimal device had an overall power conversion efficiency (AM 1.5 G, 100 mW/cm²) with 5 x 10-3 M NaOH solution as a desorption agent being 6.44% better than that of devices that had not undergone recycling and activation. [ABSTRACT FROM AUTHOR]

We report charge-transport and related physical properties of terfluorenes with various C9 substitutions. Results show that by introducing slight spiroconjugation between a core chromophore and conjugated substitutions through spiro-linking, the bulky substitution not only serves as a spatial hindrance to enhance morphological stability and emission efficiency in thin films, but also bridges and enhances intermolecular charge transport under certain situations. Interestingly, such characteristics are acquired without altering major electronic properties of core chromophores, rendering it a flexible molecular scheme for tuning characteristics of functional molecules to meet various demands of different applications. [ABSTRACT FROM AUTHOR]