An Ultraviolet‐Deposited MoO₃ Film as Anode Interlayer for High‐Performance Polymer Solar Cells

Abstract

Abstract An ultraviolet‐deposited MoO 3 film is developed as anode interlayer based on molybdenum(V) chloride as precursor. The ultraviolet‐deposited MoO 3 film is prepared from the precursor film (spin coated from its solution) with ultraviolet irradiation treatment, and the preparation process of the MoO 3 film is facile, low cost, and compatible with mass production and flexible substrate. The composition of the MoO 3 film is analyzed by X‐ray photoelectron spectroscopy. The work function as well as the surface morphology and wettability of indium tin oxide (ITO) modified by the MoO 3 film are investigated by ultraviolet photoelectron spectroscopy, atomic force microscopy, and contact angle tester, respectively, where the analyses show the ITO modified by the MoO 3 anode interlayer can offer excellent energy level alignment and interface contact with active layer. The photovoltaic performance of nonfullerene polymer solar cells (PSCs) based on the MoO 3 anode interlayer is researched with typical and relatively low‐cost PBDB‐T:ITIC as active layer, and the ITO/MoO 3 ‐based device shows the highest power conversion efficiency of 9.27% compared with the bare ITO‐based device (3.69%) and the ITO/PEDOT:PSS‐based device (9.15%). The results demonstrate the great potential of the ultraviolet‐deposited MoO 3 film as anode interlayer for high‐performance PSCs.