We investigated the effect of the morphology of 2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-OMeTAD) prepared using chlorobenzene (CB) and 1,2-dichlorobenzene (DCB) on the performance of perovskite solar cells (PSCs). We find that a more uniform and smoother spiro-OMeTAD layer was obtained using DCB than CB. The PSCs prepared using DCB exhibited a higher power conversion efficiency (PCE = 16.2%) than those obtained using CB (PCE = 14.5%). The hysteresis was reduced from 4.8% to 0.6%, with improved stability. The highest PCE of PSCs prepared using DCB was 16.6%, indicating that the use of DCB for spiro-OMeTAD processing enables the fabrication of high-performance PSCs. (C) 2017 Elsevier B.V. All rights reserved.