Abstract
An water/alcohol soluble electron-injection/hole-blocking composite layer contains a conjugated polymer grafted with a side chain crown ether and with pseudo-metallic state of metal-ion stabilized by the crown ether (to reduce electron-injection barrier and facilitate electron transport), and a polymer with hole-blocking function. This composite layer is able to improve the performance of an organic light emitting diode with oxygen- and moisture-stable cathode (such as Al and Au), and the performance of an organic solar cell.