Platinum-based poly(aryleneethynylene) polymers containing thiazolothiazole group with high hole mobilities for field-effect transistor applications

Abstract

Two solution-processable platinum-acetylide polymers functionalized with the electron-deficient thiazolothiazole spacer are synthesized and show absorption features spanning from 320 to 600 nm and optical bandgaps of 2.15 and 2.05 eV. The spin-coated polymer thin films of both materials exhibit p-channel field-effect charge transport characteristics with impressive peak field-effect charge-carrier mobilities of (2.1-2.8) × 10(-2) cm(2) V(-1) s(-1) and on/off ratios of (0.8-1.0) × 10(5) for the holes. The high hole mobility value reported for one of the polymers is among the highest reported for metallopolyynes to date. It is also shown that the hole mobility can be notably increased by extending the conjugation length of the chain from the monothienyl to the bithienyl segment on each side of the thiazolothiazole ring.