The purity of hydrothermally synthetized samples is analyzed in terms of their elemental composition (Table ) showing comparable formulation to MoS2 Comm. Often, hydrothermal preparation of MoS2 using organic precursors leads to formation of some amorphous carbon impurities . In this case, each material shows low content of carbon in comparable quantity to MoS2 Comm. Lack of nitrogen content in MoS2 TAA and MoS2 LC suggests the absence of unreacted precursor residue in the samples, whereas MoS2 TU shows a small quantity of nitrogen (1.6 wt.%), which was previously reported to increase the interlayer distance of MoS2 . The findings show correlation between the lower decomposition temperatures of TAA and LC compared to TU and the resulting nitrogen impurity content. MoS2 samples derived from TU and LC show some oxygen residue (ca. 4 wt.%), which can be a consequence of the relatively high precursor decomposition temperature (TU) and/or the high oxygen content of the precursor (LC). The analysis reveals that purity of hydrothermally synthesized MoS2 samples can be affected to some extent by the choice of sulfur precursor. ). Therefore, the expanded interlayer spacing may be a result of partial water adsorption between the MoS2 layers, as was observed previously for TAA-derived MoS2 .