Charge transport properties of pyrene and its derivatives: optoelectronic and nonlinear optical applications

The charge transport and nonlinear optical (NLO) properties of pyrene and nine of its mono-substituted derivatives have been analyzed for potential use as effective materials for organic light-emitting diode (OLED) and NLO devices at the B3LYP/6-31++G(d,p) level of theory. The subsequent charge distribution is analyzed using natural population analysis. Based on its properties, hydroxypyrene is selected for further investigation. The two-layer OLED device using hydroxypyrene and Alq3 has been analyzed according to energy level alignment and mobility computations. Obtained data point to large hole mobility and perfect alignment of the energy levels, thus suggesting that hydroxypyrene is a potential candidate for the rational design of OLED devices as a hole transport layer. The single exciton generation fraction further reveals that hydroxypyrene is a highly efficient fluorescent material with absorption and emission peaks being computed at 354 and 381 nm, respectively. These correlate well with available experimental results. Theoretically computed first hyperpolarizability together with the experimental Z -scan analysis suggests that nitropyrene is best suited for NLO applications.