We find almost the same work function for the pristine titanium substrate regions (R1) for flake 2 and flake 3 and a higher work function for the silicon substrate of flake 1. A comparably high work function  is expected for MoS2, a value of 5.4 eV was recently reported for single crystalline bulk substrates. However, for monolayer or few-layers on oxidized silicon, significantly lower values were observed ( ~ 4.5 eV) by both PEEM and Kelvin probe force microscopy (KPFM). We note that KPFM measures relative work functions, which may complicate a direct comparison of absolute values. Furthermore, a comparison to literature data has to take into account difference in the preparation method, the influence of contaminations in the case of measurements under ambient conditions, as well as the choice of the substrate, which may alter the work function of MoS2 flakes by several tenths of eV. However and most importantly, all methods agree in that the work function increases from single to few-layer MoS2. Using PEEM under UHV conditions, for MoS2 on oxidized silicon differences of 60 meV and 80 meV were observed for 1→2 and 2→3 monolayers, respectively. Thus, the geometry all spectra were taken at an incident angle of 25° with respect to the surface of the sample. This is relatively close to the grazing incidence angle for the measurements of CoPc and CoPcF16 on bulk MoS2 single crystals (20°). Thus, for preferred flat-lying molecules only a slight increase of the relative intensity of the in-plane polarized features B1 and B2 might be expected compared to bulk MoS2 single crystals, discussed in Figure (cf. e.g. Refs. for the angular dependence of Co L3 spectra). A further reason for a slightly increased intensity of B1 and B2 could be a different degree of the polarization of the synchrotron light. Considering these minor technical limitations, the µ-XAS spectra of CoPc and CoPcF16 on large MoS2 terraces (R2) in Figure are very similar to the related spectra on bulk MoS2 single crystals at grazing incidence (20°) in Figure . In both cases, the out-of-plane polarized feature A clearly dominates the spectrum. In contrast, on the oxidized silicon and titanium surfaces (regions R1 in Figure ), the molecules grow obviously in a different manner: The dominating in-plane features B1 and B2 indicate a preferred standing (edge-on) adsorption geometry, which can be related to the weaker molecule-substrate interaction with increasing (micro-)roughness of the substrates (i.e. the substrates are not atomically flat). Such effects were reported for different molecules (see, e.g. Refs. ). Most importantly, the ratio of A/B intensities of the Co L3 spectra for the regions R3 and R4 deviate distinctly from the regions R2 of the MoS2 flakes on oxidized titanium (Figure ), indicating significant tilt angles of the molecules to the surface plane or a disordered growth. This effect is observed to some weaker extent also on the region R2 on oxidized silicon (Figure ), where Figure In conclusion, we found that the orientation of cobalt phthalocyanines on technically relevant, small-sized thin-layers of MoS2 flakes is significantly different compared to bulk MoS2. This demonstrates that the molecular orientation on small sized (monolayer) TMDC flakes cannot be simply deduced from the orientation of organic molecules on related bulk substrates. For the understanding of electronic and optic interactions at such interfaces, different molecular orientations should be considered. From our perspective, especially the situation between electrodes with small distances seems to be critical, in particular if the evaporation of molecules occurs after the deposition of electrode structures.