The preparation and characterization of Cu2O crystals by a simple surfactant-free electrodeposition are presented. The shape evolution of Cu2O crystals owing to the change of reaction time and PH is investigated. The shape and size of Cu2O crystals can be controlled simply by reaction time and PH without any surfactant in the electrodeposition. The Cu2O crystals obtained by the electrodeposition can be used in the organic/inorganic hybrid detectors and the films obtained can be used in organic/inorganic hybrid solar cells. (C) 2016 The Electrochemical Society. All rights reserved.