Improvement of the Optoelectronic Properties of Terazulene Molecules for Organic Solar Cell Applications

We have designed six molecular donors based on three azulene units connected serially with different substituted groups. The electronic structures, optoelectronic properties and absorption spectra of molecular donors are calculated by using time-dependent density functional theory (TD-DFT). The studied molecules demonstrate good properties with low energy gap, small exciton binding energy, high open circuit voltage and broad absorption spectrum. The molecular donor (MD5) is identified as the promising candidate of the organic solar cell because of the most enhanced in optical absorption, energy gap, open circuit voltage, energy driving force, exciton binding energy.