Hole-Transporting Spirothioxanthene Derivatives as Donor Materials for Efficient Small-Molecule-Based Organic Photovoltaic Devices

A new class Of hole-transprorting spirothicixanthene derivatives has been synthesized and characterized. Their photophysicali, electrochemical and thermal properties have been studied. These,compounds :exhibit :high hole mobilities of up to 1 X 10(-3) cm(2) V-1 s(-1), determined by using thin :Sin transistor technique. In addition, these spirothithantherie, derivatives are promising donor materials in the construction of,high performance organic photovoltaic (OPV) devices. With a very-low dopant concentration: of 7%, highly efficient small molecule-based (OPV devices with high short-circuit current density Of 10:83 mA open-circuit voltage of 0.94 V, and: high power conversion efficiency of 5.40% (the highest PC-F of 5:46%) have been realized.