Exceptionally stable CH3 NH3 Pbi3 films in moderate humid environmental condition

Abstract

Methylammonium lead iodide (CH3NH3PbI3) based perovskite materials have drawn intense interests due to the excellent photovoltaic energy conversion capability the power conversion efficiency (PCE) of perovskite solar cell has been boosted to 20.1%. [1] Recent investigations have gained comprehensive understandings about the materials and operational principles as well as accumulated rich experiences in the device fabrication. [2,3] It has been increasingly acknowledged that the major concern regarding this technology is the poor device stability. [4] Most recently, an extensive investigation shows that in 25% relative humidity (RH) the absorbance of the perovskite CH3NH3PbI3 film decays to half of its original value in 57 d (t1/2). While in moderate moisture (40% RH), the t1/2is only 26 d. The high sensitivity to moisture poses severe challenge in terms of the practical applications. [5].