Facile solvent-thermal synthesis of ultrathin MoSe2 nanosheets for hydrogen evolution and organic dyes adsorption

The flower-like MoSe2 nanospheres with average size of 200 nm which composed of ultrathin nanosheets were synthesized by facile solvent-thermal method. AFM analysis indicated that the thickness of the MoSe2 nanosheets could be changed from 3.4 to 6.4 nm by changing the chains of n-alcohol solvent. The as prepared MoSe2 nanosheets in ethanol solvent exhibited the best electrochemical performance and the highest adsorption capability as compared to samples synthesized in other n-alcohol solvent with longer chains. It was due to MoSe2 synthesized in ethanol exhibited higher crystallinity and better wettability than other samples. The maximum adsorption capability of Rhodamine B (RhB) on MoSe2 nanosheets reached 133 mg g−1 in 5 min, while the same adsorption capabilities on activated carbon need 20 min. Electrochemical results exhibited a relatively small onset potential (120 mV), small Tafel slope (71 mV/dec), and long term stability for MoSe2 synthesized in ethanol which making it a promising candidate for hydrogen evolution reaction.