The paper reports first results of research aiming at the preparation of ionically conductive monograin membranes for photoelectrochemical solar energy storage. Polyurethane and PFSA solutions have been mixed to prepare composite membranes which in it's polyurethane part allow for the fixation of semiconductor single crystalline grains, while the PFSA component should allow for the establishment of ionically conductive pathways for ions through the membranes. This goal was achieved at least partly as is demonstrated by the conductivity results obtained. Although, the membranes change considerably with respect to their mechanical appearance.
