Green synthesis of MoSe2 nanosheets based on hydrogen bond with high photodegradation performance

Abstract

MoSe2 is listed as a very promising photocatalyst candidate due to its unique 2D nanostructure and narrow band gap, yet how to obtain it in a green and facile way is still a challenge. In this work, multilayered MoSe2 nanosheets were successfully prepared by a hydrothermal method using a hydrogen bond-based melamine-oxalic acid polymer as the reducing agent, surfactant and template. X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), Bruno-Emmett-Taylor (BET), X-ray photoelectron spectroscopy (XPS) and UV–Vis spectroscopy were used to characterize the composition, morphology, specific surface area and band gap of the product. In addition, the photodegradation experiments of Rhodamine B and methylene blue were carried out by using such MoSe2 nanosheets. The degradation of Rhodamine B reached 94.4% in 40 min, while the degradation of methylene blue reached 95.1% in 50 min, respectively. After four cycles of degradation, it still maintained a high catalytic activity. The formation mechanism of the MoSe2 nanosheets and the photocatalytic mechanism have also been explained.