Chien-Huang Tsai

The effects of solvent on the electrochromic properties of poly(3,4-ethylenedioxythiophene)

In this study, we have investigated the solvent effect on the electrochromic properties of poly(3,4-ethylenedioxythiophene) (PEDOT). The results suggest a conformational change of the PEDOT chains from the coil structure into a linear structure in methyl sulfoxide (DMSO). This transition enhances the charge hopping in the polymer leading to better conductivity and electroactivity. We believe that these factors are also responsible for the higher electrochromic contrast and efficiency. Moreover, the results also suggest that the linear conformation is more favorable for the ionic transfer during the electrochemical reaction. This can promote the long-term stability of the PEDOT for electrochromic application.

Improving stability of photoluminescence of ZnSe thin films grown by molecular beam epitaxy by incorporating Cl dopant

This investigation studies the effect of chlorine (Cl) dopant in ZnSe thin films that were grown by molecular beam epitaxy on their photoluminescence (PL) and the stability thereof. Free excitonic emission was observed at room-temperature in the Cl-doped sample. Photon irradiation with a wavelength of 404 nm and a power density of 9.1 W/cm2 has a much stronger effect on PL degradation than does thermal heating to a temperature of 150 °C. Additionally, this study shows that the generation of nonradiative centers by both photon irradiation and thermal heating can be greatly inhibited by incorporating Cl dopant.