Cl-doped MAPbI3 Perovskite Single Crystal Inducing a High Thermoelectric Effect

Abstract

Recently, the methylammonium lead triiodide perovskite (MAPbI3) has shown great development potential in the solar cell field, and its efficiency as a perovskite solar cell (PCE) has reached 25.2%. However, poor stability is still a problem that restricts its wide application. Compared with the polycrystalline film material of MAPbI3 perovskite, the single crystal MAPbI3 material is much more stable. In addition, it possesses the advantages of ultra-low thermal conductivity and easily regulated electrical conductivity, so this kind of single crystal material has also a broad application prospect in thermoelectric fields. In this letter, we show that the chlorine (Cl) ion-doped MAPbI3 perovskite single crystal was an effective method, which greatly improved the carrier concentration and electrical conductivity of the MAPbI3 single crystal. When the dopant proportion of I:Cl was 100:1, we obtained the highest power factor (PF) of 2.526 µW/m K2 at 30 °C for MAPbI3 single crystal. These results provide an experimental basis for the transformation and application of this kind of perovskite single crystal materials in high efficiency thermoelectric fields.