Self-assembly montmorillonite nanosheets supported hierarchical MoS2 as enhanced catalyst toward methyl orange degradation

Abstract

Layered MoS2 and montmorillonite nanosheets were hybridized through a simple in-situ hydrothermal synthesis to develop an efficient catalyst (MoS2/MMT) for better exposure of the active sites on MoS2 toward Methyl Orange (MO) degradation, enable MoS2/MMT hybrid to achieve an excellent catalytic performance on MO removal. The characterizations of MoS2/MMT, based on XRD, FTIR, XPS, SEM, TEM, TGA, UV, contact angle detector and laser particle size analyzer, suggested that the montmorillonite nanosheets self-assemble into a cross-linked structure first, then the MoS2 nanosheets grew along the montmorillonite nanosheets surface, formed a cross-link atypical grid construction. The hybrid exhibited an excellent catalytic decomposition (98.6%) of MO into 4-amino-dimethylaniline and sulfanilic acid, much higher than that (48.6%) of pure MoS2, and the corresponding reaction rate of MoS2/MMT is about 8 times of MoS2. The superb decomposition capacity was found to be attributed to the more available of active sites and the high hydrophilicity of MoS2/MMT. The former greatly improved the hydrolysis of NaBH4 reductant, while the latter brought the catalyst a good dispersion in aqueous solutions. Furthermore, the hybrid performed a good catalytic reusability and stability. It is demonstrated that the MoS2/MMT hybrid might be an outstanding material in catalytic filed and water treatment.