Disclosed are photoconductive elements including a conductive support, e.g., an electrically conductive film, drum, or belt, on which a negatively chargeable photoconductive layer is disposed. An electrical barrier layer is disposed between the conductive support and the photoconductive layer. The barrier layer provides a high energy barrier to the injection of positive charges, but transports electrons under an applied electric field. In embodiments, the barrier layer can transport charge by electronic, or both electronic and ionic mechanisms, and, is not substantially affected by humidity changes. The barrier layer includes a polyester-co-imides, polyesterionomer-co-imides, or polyamide-co-imides having covalently bonded as repeat units in the polymer chain, aromatic tetracarbonylbisimide groups of the formula: ##STR1## wherein Ar.sup.1 and Ar.sup.2 respectively represent tetravalent or trivalent aromatic groups of 6 to about 20 carbon atoms, and X is O, C(CF.sub.3).sub.2, S.dbd.O or SO.sub.2.