Highly efficient and stable planar heterojunction perovskite solar cells via a low temperature solution process

Abstract

Both high efficiency and good stability of organometal trihalide perovskite solar cells are of central importance for their practical application. Here we report the fabrication of highly efficient and stable planar heterojunction perovskite solar cells through a simple and low temperature solution process. By combining the slow growth of the perovskite film and the introduction of a ZnO interlayer, a maximum power conversion efficiency of 16.8% was achieved. More importantly, the devices showed excellent stability, which can maintain their almost original performance after storing in ambient air for two months. It has been found that the ZnO interlayer is critical in enhancing the efficiency and stability of the devices. Furthermore, the low temperature solution process and the planar device structure used in this work are well compatible with the large-area and flexible substrates.