Proceedings of International Conference Asia-Pacific Hybrid and Organic Photovoltaics (AP-HOPV17)
Publication date: 7th November 2016
A quasi two dimensional (2D) perovskite containing a little amount of hydrophobic alkylamine group as a part of A-site cation of a lead halide perovskite structure is promising because it will provide long term durability against humidity to the organic-inorganic hybrid perovskite solar cell which has been known as a next new generation low-cost and high-performance electric power source. However, the photovoltaic properties of 2D perovskite itself has not been investigated well because of low possibility to obtain a good photon harvesting efficiency and power conversion efficiency (PCE) due to its narrow light absorption region although it was known that the 2D perovskite has a unique charge separation ability and charge transport characters due to layered structure constructed by self-organization. In this presentation, we investigated orientation controlling method for a 2D perovskite crystal ((BA)2PbI4) consisting of a lead iodide and a butylamine hydroiodide as a hydrophobic cation and examined its effect on photovoltaic properties of solar cells. It was found that the crystalline orientation of 2D perovskite can be successfully controlled by optimizing preparation conditions of spin-coating for 2D perovskite layer and the oriented nanostructure of scaffold layer which assists a crystalline growth of 2D perovskite. As the result, crystalline orientation-controlled (BA)2PbI4 solar cell prepared on TiO2 oriented nanowire arrays showed higher PCE than that of non-controlled 2D perovskite solar cell prepared on planer TiO2 film scaffold.