Electrochemical determination of the energy level of organic/polymeric materials

We focus on the study of energy level structure of organic systems(taking A lQ(3) for example) using two newly developed electrochemical methods (deriv ative voltammetry and coulomb-potential spectroscopy), and devote our atten tion to comparing the accuracy of these new methods with conventional metho ds. The experimental values of the HOMO and the LUMO positions of AlQ(3) an d PVK are in good agreement with the results determined by the photoemissio n analysis. The experimental band gap values for AlQ(3) and PVK obtained vi a two new methods are also in excellent agreement with the band gap values deduced by the optical absorption spectroscopy. The resulting organic/polym eric electroluminescent devices based on matching energy level of organic/p olymeric system exhibit a high luminescent efficiency.