Origin of the Thermal Instability in CH 3 NH 3 PbI 3 Thin Films Deposited on ZnO

The rapid development of organometal halide perovskite solar cells has led to reports of power conversion efficiencies of over 20%. Despite this excellent performance, their instability remains the major challenge limiting their commercialization. In this report, we systematically investigate the origin of the thermal instability of perovskite solar cells fabricated using ZnO electron transport layers. Through in situ grazing incidence X-ray diffraction experiments and density functional theory calculations, we show that the basic nature of the ZnO surface leads to proton-transfer reactions at the ZnO/CH3NH3PbI3 interface, which results in decomposition of the perovskite film. The decomposition process is…

• CR
  Canada Research Chairs
• CN
  Consiglio Nazionale delle Ricerche
• NS
  Natural Sciences and Engineering Research Council of Canada