Optimizing CuO p-type dye-sensitized solar cells by using a comprehensive electrochemical impedance spectroscopic study - Langmar, Oliver; Ganivet, Carolina R.; Torre, Gema de la; Torres, Tomas; Costa, Rubén D.; Guldi, Dirk M. (Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2016)