Humidity-insensitive fabrication of efficient perovskite solar cells in ambient air

Fabrication of perovskite solar cells (PSCs) is highly humidity-sensitive. In this paper, humidity-insensitive fabrication (HIF) of efficient CH3NH2PbI3 (MAPbI(3)) PSCs using an antisolvent method is demonstrated. Characterizations including scanning electron microscope (SEM), X-ray diffraction (XRD), UV-vis absorption and steady-state photoluminescence (PL) of the MAPbI(3) films prepared in a glovebox(similar to 0% RH) and 50% RH ambient air using the antisolvent method are carried out. The quality of the MAPbI(3) films shows no obvious difference in these two cases. By analyzing the crystallization processes, the greatly suppressed influence of humidity is ascribed to the rapid crystallization process due to the antisolvent method. The photovoltaic performances and storage stability of MAPbI(3) PSCs prepared at a series of relative humidity (RH) levels below 60% are found similar. Their average power conversion efficiency (PCE) is over 15% with the best PCE of 16.9%. In addition, the influence of absorbed water in the hydrophilic precursor to MAPbI(3) films and associated solar cells is investigated. The influence of equal molar absorbance of H2O is found ignorable. It is concluded that anti solvent method is an ideal HIF route for fabrication of efficient PSCs in ambient air and may pave the way for massive and low-cost manufacturing of solar panels.