LAUSR

Abstract The photovoltaic efficiency and stability of planar p-i-n perovskite solar cells (PVSCs) are largely dependent on charge carrier dynamics and surface properties of hole transport layers (HTLs). Herein we introduce ammonium metatungstate hydrate (AMH) into poly(3,4-ethylenedio-xythiophene): poly(styrenesulfonate) (PEDOT:PSS) for the first time. The results showed that AMH dopant could not only enhance the conductivity of PEDOT:PSS film without impact its transmissivity, but also change the surface property of HTL after the annealing process of composite HTL. The composite HTL yields the perovskite with large average grain size, smooth and dense film. Consequently, the average power conversion efficiency (PCE) of 14.61% was achieved in PVSCs based on the optimal concentration of AMH modified PEDOT:PSS, with improved short-circuit current (JSC) and fill factor (FF). Meanwhile, the ambient stability of AMH modified devices is also enhanced by more than 3 times compared with the control devices.