Cobalt phthalocyanine (CoPc, Sigma-Aldrich Chemie GmbH) and perfluorinated cobalt phthalocyanine (CoPcF16, Sigma-Aldrich Chemie GmbH) were deposited on bulk MoS2 (2D semiconductors Inc. USA) by thermal evaporation under ultra-high vacuum (UHV) conditions (base pressure about 1•10 -9 mbar). The evaporation chamber was directly attached to the spectrometer chamber. The nominal film thickness was determined using a quartz crystal microbalance, setting the mass density of CoPc and CoPcF16 at 1.6 g/cm 3 and 1.8 g/cm , respectively, and checked by the comparison of XPS peak areas for bulk samples.