Abstract
Here in design and synthesized new dimer organic metal free dyes based on various donor moieties along with dihydrothieno [3,4-b][1,4] dioxine and cynoacrylic acid are bridge and acceptor respectively. The influence of dye consist various donor moieties like phenothiazine (PTZ), phenoxazine (POZ) and carbazole (CBZ) studied carefully. The same donor and acceptor groups optical and electrochemical properties change when we change donor groups. The all dyes structure geometry optimization and energy levels (HOMO-LUMO) was calculated by density functional theory (DFT) with B3LYP/6-31G(d.p) basis set. It is evident from the studies that the strong electron withdrawing donor moiety based dye, POZ-102 exhibit highest short circuit current density (Jsc), open circuit voltage (Voc) and efficiency (η = 6.4%). The inside device electron recombination and electron lifetime was calculated by impedance spectroscopy and open circuit voltage decay techniques. In last the highest efficiency achieved POZ-102 dye based device checked long term stability up to 500hr under 100 mW/cm2 light illumination.
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•New series of organic metal free dimer dyes based on dihydrothieno [3,4-b][1,4] dioxine bridge moiety were synthesized.•Synthesized dyes are used in dye sensitized solar cells.•Optical and electrochemical measurements of the three dyes were studied.•Phenothiazine based POZ-102 dye exhibit highest Jsc, Voc and efficiency (6.40%).•Optimized all dye structure and geometry by density functional theory.