A starburst molecule (T) with triphenylamine (TPA) and benzothiodiazole (BTD) as constructing units was synthesized
via two step Heck coupling reaction. As compared with its linear counterpart, it shows better solubility and amorphous
film-forming ability. Spectroscopic properties show that it emits red light with emission peak at 651 nm in CH<sub>2</sub>Cl<sub>2</sub>. The
red light emitting arises from the intramoleculasr charger transfer state. White light emitting diode (WLED) was
fabricated with the starburst molecule as red light emitting composite. The luminance and efficiency maximum was
3960 cd/m<sup>2</sup>, and 1.22 cd/A for the WLED device with only 0.05%.(W/W) doping content of the light emitting
composite. The high performance of WLED is attributed to the high chromorphore density and electron coupling effect
of multi-branches. It is reasonable to conclude that starburst structure is superior to its linear and less branch
counterparts in the fabrication of LED devices.
Two solution-processible linear organic conjugated molecules with an electron-deficient core and
triphenylamine (TPA) end groups, TPA-DCM-TPA and TPA-th-TPA, were used as
donor and acceptor materials respectively in fabricating all organic solar cells (OSCs) by spin-coating
method. Both the LUMO and HOMO energy levels of TPA-th-TPA are lower than those of
TPA-DCM-TPA, which makes TPA-th-TPA a suitable acceptor for the OSCs with TPA-DCM-TPA as
donor. The all OSC based on the blend of TPA-DCM-TPA and TPA-th-TPA (1:1, w/w) with LiF/Al as
cathode, showed the photo-sensitivity in a broad wavelength range from 380 nm to 700 nm, high
open-circuit-voltage (<i>V<sub>oc</sub></i>) of 1.21 V, and a power conversion efficiency of 0.21% under the illumination
of AM 1.5, 100 mW/cm<sup>2</sup>. The high <i>V<sub>oc</sub></i> of the device is benefited from the higher LUMO energy level
of the TPA-th-TPA acceptor in comparison with that of the traditional acceptor PCBM.
Three copolymers containing alternating rigid and flexible blocks and five PPVs oligomers have been designed and synthesized for the best understanding the relationship of molecular structure and properties of as LED. The results showed that the solubility was improved and the peak positions of absorption and emission spectra were shifted to longer wavelength with different groups substituting.