Charge injection and transport studies of poly(2,7-carbazole) copolymer PCDTBT and their relationship to solar cell performance

► The charge injection and transport properties of a poly(2,7-carbazole) copolymer, PCDTBT, is probed by DI-SCLC technique. ► The hole mobilities are in the range of 0.4-3.0 × 10−4 cm2/Vs. ► MoO3 is a better hole injection layer than PEDOT:PSS for PCDTBT. ► PCDTBT possesses a large energetic disorder of ∼129 meV, which is higher than that of P3HT. ► The correlation between energetic disorder and OPV device performance is addressed.