Soluble tetratriphenylamine Zn phthalocyanine as Hole Transporting Material for Perovskite Solar Cells

Perovskite solar cells have been constructed under the standard procedure by employing soluble tetratriphenylamine-substituted Zn phthalocyanine as hole transporting material. Solution processed device construction was carried out under ambient conditions of 50-60% ambient humidity. Triphenylamine substitution played the double role of imparting solubility to the core metal phthalocyanine as well as to introduce electron-rich ligands, which could enhance the role of Zn phthalocyanine as hole transporter. Indeed, the obtained material was functional. The present data highlight tetratriphenylamine-substituted Zn phthalocyanine as hole transporting material but also highlight the importance of the presence of a buffer layer between the perovskite layer and the hole transporting layer. Thus the efficiency of the cells was 9.0% in the absence but increased to 13.65% in the presence of Al2O3 buffer layer. (C) 2016 Elsevier Ltd. All rights reserved.