COMPUTATIONAL DESIGN OF NOVEL COUMARIN SENSITIZERS TO IMPROVE THE EFFICIENCY OF SOLAR CELLS

Abstract Dye Sensitized Solar Cells (DSSCs) are the most efficient third-generation solar cell to use because they have good chemical stability, low production cost, and environmental-friendly. Dyes have an important role on DSSCs, which is functioned as sensitizer (light-sensitizer). In this study, the modification of dyes was performed to produce a better light-absorption value. This study analyzed the D– π –A type of dyes (Donor– π conjugation–Acceptor) with coumarin donor and formic acid acceptor, then the π- conjugation was varied with butadiene, dicyclopentadiene, dipirol, difuran, and dithiophene molecules which later symbolized as dyes 1, 2, 3, 4, and 5. This study used Gaussian 16W program packaged with DFT (Density Functional Theory) and TD-DFT (Time Dependent-DFT) measurement methods as well as B3LYP/6-31G Basis Set. The analysis descriptors were HOMO (Highest Occupied Molecular Orbital) and LUMO (Lowest Unoccupied Molecular Orbital energies, band gap (∆E), HOMO and LUMO contours, excitation energy (Eeks), excitation wavelength (λeks), oscillator strength (f) and LHE (Light Harvesting Efficiency). The measurement results showed that all dyes were capable of absorbing light unto the visible light area and the dye 3 produced the light absorption on the longer wavelength. It has been concluded that coumarin-based D-π-A type of dyes can improve the efficiency of light absorption on DSSCs.