Donor–acceptor cocrystal based on hexakis(alkoxy)triphenylene and perylenediimide derivatives with an ambipolar transporting property

Abstract

An organic donor–acceptor cocrystal with an ambipolar transporting property was constructed based on N,N′-bis(1-ethylpropyl)-perylene-3,4,9,10-tetracarboxylic diimide (EP-PDI) and 2,3,6,7,10,11-hexakis-(hexyloxy)-triphenylene (H6TP). The cocrystal with an alternating stacking of H6TP and EP-PDI molecules was formed through both drop-casting and spin-coating processes, especially at the optimized ratios of H6TP/EP-PDI (2/1, 1/1). The formation of the cocrystal was driven by the strong π–π interaction and the weaker steric hindrance, resulting from the smaller side groups, between the donor and acceptor molecules. Field effect transistors (FETs) based on the H6TP/EP-PDI cocrystal exhibited relatively balanced hole/electron transport, with a hole mobility of 1.14 × 10⁻³ cm² V⁻¹ s⁻¹ and an electron mobility of 1.40 × 10⁻³ cm² V⁻¹ s⁻¹.