Influence of thermal treatment on the structural and optical properties of methoxy-substituted 2, 4-diphenyl quinoline

Abstract

Herein, we report blue-emitting methoxy-substituted 2, 4-diphenyl quinoline phosphor prepared using acid-catalyzed Friedlander reaction along with the enhancement in the phase purity due to employed thermal treatment in Ar atmosphere. Improvement in the phase purity of the phosphor leading to a change in their optical properties is reported. XRD and FTIR analyses confirm the formation and improvement in the phase purity of the phosphor. TG/DTA analysis endorses the change in their behavior and thermal stability. The modification in optical band gap of the phosphors due to thermal treatment has been confirmed from the UV–vis spectroscopy. Enhancement in the fluorescence intensity of blue-emitting phosphor due to thermal treatment has been described through photoluminescence analysis. Luminescence decay profile has also been recorded using time-correlated single-photon counting (TCSPC) system for the lifetime analysis of the phosphors which supports the obtained PL analysis. The overall study indicates that methoxy-substituted 2, 4-diphenyl quinoline phosphor which was annealed at 90 °C in Ar atmosphere serves better fluorescence intensity, thermal stability and lifetime profile, and may be utilized for the organic display applications.