LAUSR

ABSTRACT Coumarin derivatives are used in a wide range of applications, such as optoelectronics, photovoltaics and dye lasers. Therefore they have attracted significant research interest. In this regard, novel coumarin dye molecules were synthesised and characterised by spectroscopic techniques. The synthesised dyes were studied for optical (linear and nonlinear), frontier molecular orbital analysis (using cyclic voltammetry and DFT calculations) and the current-voltage (I-V) studies for photosensitization behaviour on TiO2 nanoparticles. The TiO2 nanoparticles were synthesised by the sol-gel method and characterised by XRD, EDAX and SEM analysis. The results showed that the dye molecules possess good light-absorbing capability with a high molar absorption coefficient and also exhibited the good nonlinear optical (NLO) response. Moreover, the I-V characteristics suggest the efficacy of synthesised dyes for photovoltaic applications.