ZnSe quantum dots downshifting layer for perovskite solar cells

摘要

To date, the instability of organometal halide perovskite solar cells(PSCs) has become the focus issue that limits the development and long-term application of PSCs. Both the ultraviolet(UV) rays in sunlight and moisture in air can significantly accelerate the disintegration of the perovskite. Here, we introduced a Zn Se quantum dots layer as downshifting materials, which was spin-coated onto the backside of PSCs.This layer converted the UV rays into visible light to prevent the destruction of PSCs as well as increase the light harvesting of the perovskite layer. Under the UV irradiation in the moisture ambient(40%), the destruction speed of the unencapsulated perovskite films were also delayed evidently. In addition, the power conversion efficiency(PCE) of the PSCs was increased from 16.6% to 17.3% due to the increase of the visible light absorbance of the perovskite.