Synthesis, optical and electrochemical properties of the A–π-D–π-A porphyrin and its application as an electron donor in efficient solution processed

Abstract

<div> A conjugated acceptor&ndash;donor&ndash;acceptor (A&ndash;&pi;-D&ndash;&pi;-A) with the Zn-porphyrin core and the di-cyanovinyl</div> <div> substituted thiophene (A) connected at meso positions denoted as VC62 was designed and synthesized.</div> <div> The optical and electrochemical properties of VC62 were investigated. This new porphyrin exhibits a</div> <div> broad and intense absorption in the visible and near infrared regions. Bulk-heterojunction (BHJ) solution</div> <div> processed organic solar cells based on this porphyrin, as electron donor material, and PC71BM ([6,6]-</div> <div> phenyl C71 butyric acid methyl ester), as electron acceptor material, were fabricated using THF and a pyridine&ndash;</div> <div> THF solvent exhibiting a power conversion efficiency of 3.65% and 5.24%, respectively. The difference</div> <div> in efficiencies is due to the enhancement of the short circuit current Jsc and FF of the solar cell,</div> <div> which is ascribed to a stronger and broader incident photon to current efficiency (IPCE) response and a</div> <div> better balanced charge transport in the device processed with the pyridine&ndash;THF solvent</div>