A transparent, flexible silicone rubber ([SiO(CH3)2]n) surface was photochemically modified into a photoluminescent material using a 193 nm ArF excimer laser. The photomodified silicone rubber emitted white light under a 325 nm He–Cd laser or a 375 nm light-emitting diode. The chemical bonding of the photomodified silicone rubber was found to be similar to that of a silica-like silicone, as analyzed by Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. The photoluminescence of the rubber originated from oxygen deficiency centers and peroxy centers of the silica structure in the photomodified silicone rubber. Fine particles 200 nm in diameter were also formed in the photomodified silicone rubber to enhance the intensity of the photoluminescence.
Photoluminescence spectra of silicone rubber ([SiO(CH 3 ) 2 ] n ) photochemically modified by a 193 nm ArF excimer laser was found to be controllable. Compared with the modification in air, the photoluminescence spectra could be blueshifted by the modification in vacuum or the additional irradiation of ArF excimer laser in vacuum after the modification in air. To redshift, on the other hand, the additional irradiation of a 157 nm F 2 laser in air after the modification in air, the modification in oxygen gas, or the postannealing after the modification in oxygen gas was effective. The blue and redshifts of the photoluminescence were essentially due to the acceleration of reduction and oxidation reactions of silicone rubber, respectively, because the photoluminescence derives its origin from oxygen deficiency centers and peroxy centers of the silica structure in the modified silicone rubber. On the basis of the spectra changes, colorful light-guiding sheets made of silicone rubber under illumination of a 375 nm light-emitting diode were successfully fabricated for cellular phone use.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.