A collector element for a thermionic electric converter that reduces electron scatter and improves conversion efficiency is provided. The collector element includes an outer casing and a highly charged member surrounded by insulating layers that minimize loss of static charge on the highly charged member. The collector element additionally includes a conductive layer of copper sulfate gel impregnated with copper wool fibers. Copper sulfate gel minimizes electron scatter, while providing advantageous electrical properties. The copper wool fibers are in electrical contact with a plurality of ancillary buses which transmit electrical energy to a main bus that provides the electrical energy collected to an external circuit. The main bus is also in electrical contact with the conductive layer.