A new approach to the polymeric semiconductor

As pi conjugated material PF (Polyfluorene) has shown strikingly new features of optoelectronic process which has drawn more attention in the industrial production for white light emitting polymer diode(PLED). It has shown emission of light in the entire visible spectrum. Their main advantages are suitable electrochemical stability. By appropriate chemical modification it is possible to tune up this material according to the application. Besides, for their excellent HOMO- LUMUO energy level polyfluorene posses efficient charge transport process. But still there are some problems with their imposed quantum efficiency, unbalanced mobilities of electron and holes, unwanted green emission and another main problem of fluorine based semiconductor is electrical degradation which frequently occurred in these material resulting low emission band. One of the taken approaches for mitigation of these problems is introduction of either electron donor or electron acceptor co-polymer into the main polymer backbone as side chain or end cap.

Critical commentary on Bangladesh's election eve (The daily Prothom Alo in Bengali)

America looking to future

Barack Obama's speech on the Democratic National Convention 2008