Semiconducting material comprising an electron transport matrix compound comprising at least one electron transporting structural moiety and at least one polar structural moiety, the at least one polar structural moiety being selected from a) a structural moiety consisting of one atom of 15 th group of the Periodic Table and one atom of 16 th group of the Periodic Table linked together by a covalent bond, or b) from a heteroaryl selected from pyridine-2-yl, pyridine-4-yl, quinoline-4-yl and 1,3,5-triazine-2-yl, or c) from a benzimidazolyl moiety having formula (Ia) or (Ib) wherein the dashed line represents the bond attaching the benzimidazolyl moiety of formula (Ia) or (Ib) to other structural moieties of the molecule, R 1 and R 2 are selected from (i) C 1 -C 24 alkyl, (ii) C 3 -C 24 cycloalkyl, (iii) C 6 -C 24 aryl, (iv) C 7 -C 24 arylalkyl, (v) C 3 -C 24 heteroalkyl or C 4 -C 24 heterocycloalkyl or C 8 -C 24 aryl-heteroalkyl each comprising at least one heteroatom selected from Si and Ge, (vi) C 2 -C 24 heteroalkyl or C 3 -C 24 heterocycloalkyl or C 7 -C 24 aryl-heteroalkyl each comprising at least one heteroatom selected from B and P, and from (vii) C 2 -C 24 heteroaryl comprising up to 4 heteroatoms independently selected from N, O and S; wherein the at least one electron transporting structural moiety comprises a benzo-naphtofurane structural moiety, with the proviso that the case that the benzo-naphtofurane structural moiety has the structure (IIa) and the polar structural moiety has the structure (Ib) is excluded. a) a structural moiety consisting of one atom of 15 th group of the Periodic Table and one atom of 16 th group of the Periodic Table linked together by a covalent bond, or b) from a heteroaryl selected from pyridine-2-yl, pyridine-4-yl, quinoline-4-yl and 1,3,5-triazine-2-yl, or c) from a benzimidazolyl moiety having formula (Ia) or (Ib) wherein the dashed line represents the bond attaching the benzimidazolyl moiety of formula (Ia) or (Ib) to other structural moieties of the molecule, R 1 and R 2 are selected from (i) C 1 -C 24 alkyl, (ii) C 3 -C 24 cycloalkyl, (iii) C 6 -C 24 aryl, (iv) C 7 -C 24 arylalkyl, (v) C 3 -C 24 heteroalkyl or C 4 -C 24 heterocycloalkyl or C 8 -C 24 aryl-heteroalkyl each comprising at least one heteroatom selected from Si and Ge, (vi) C 2 -C 24 heteroalkyl or C 3 -C 24 heterocycloalkyl or C 7 -C 24 aryl-heteroalkyl each comprising at least one heteroatom selected from B and P, and from (vii) C 2 -C 24 heteroaryl comprising up to 4 heteroatoms independently selected from N, O and S; wherein the at least one electron transporting structural moiety comprises a benzo-naphtofurane structural moiety, with the proviso that the case that the benzo-naphtofurane structural moiety has the structure (IIa) and the polar structural moiety has the structure (Ib) is excluded. (i) C 1 -C 24 alkyl, (ii) C 3 -C 24 cycloalkyl, (iii) C 6 -C 24 aryl, (iv) C 7 -C 24 arylalkyl, (v) C 3 -C 24 heteroalkyl or C 4 -C 24 heterocycloalkyl or C 8 -C 24 aryl-heteroalkyl each comprising at least one heteroatom selected from Si and Ge, (vi) C 2 -C 24 heteroalkyl or C 3 -C 24 heterocycloalkyl or C 7 -C 24 aryl-heteroalkyl each comprising at least one heteroatom selected from B and P, and from (vii) C 2 -C 24 heteroaryl comprising up to 4 heteroatoms independently selected from N, O and S; wherein