Hybrid Phase MoS₂ as a Noble Metal-Free Photocatalyst for Conversion of Nitroaromatics to Aminoaromatics

Abstract

Molybdenum sulfide has attracted intense attention owing to unique heteromorphism. A natural molybdenum sulfide shows a semiconductive 2H crystal structure, while another metallic 1T-MoS2 exhibits a higher catalytic activity. However, the strict synthetic condition and the metastable property of 1T-MoS2 have limited its application. Hybrid-phase 1T/2H-MoS2 possesses both higher catalytic activity than 2H-MoS2 and better thermal/chemical stability than 1T-MoS2, which is a more promising candidate in the catalytic field. As for photocatalytic field, 2H-MoS2 has been only used as a cocatalyst but not as an individual photocatalyst due to its fast electron–hole recombination level and nonideal surface active site nature. Hybrid-phase MoS2 would provide a proper solution for individual MoS2 as a photocatalyst because 1T sites can collect photoelectrons and provide active sites for various reactions. In this work, we report a hybrid-phase MoS2 synthesized by a simple hydrothermal method, which is applied to the photocatalytic conversion of a series of nitroaromatics to aminoaromatics. The reactions are not favorable with natural 2H-MoS2, which reveals new potential of MoS2 as a noble metal-free photocatalyst.

Electrochemical detection and catalytic reduction of nitrobenzene using a bimetallic NiS2/Fe3S4 magnetic heterostructure: an innovative approach for environmental remediation

“…Top of Form Catalytic reduction is one of the most promising methods for removing nitrobenzene from contaminated wastewater. 34,35 The process involves a catalyst that breaks down nitrobenzene into less harmful by-products. The reduction of nitroaromatics generally uses catalysts made of noble metals (such as Au, Ag, Pd, and Pt) together with excessive quantities of substances that aid in the reduction process.…”

Edge Rich Ultrathin Layered MoS2 Nanostructures for Superior Visible Light Photocatalytic Activity

“…However, the high cost of noble metal limits their use on a large scale . The applications of several photocatalysts such as the Cr, Ag, Cd, and Ni/MoS 2 composites are also limited because of their high toxicity, relatively small-scale production, and lack of stability. − Besides the ineffective exploitation of visible light, the practical applications are also hindered due to a few constraints like low adsorption ability to hydrophobic pollutants, first aggregation trend, and challenge of electron–hole separation. − Interpreting these concerns, MoS 2 nanostructures have been further studied for the application of photocatalysis for their low cost, abundant in the Earth’s crust, outstanding durability, and large-scale production . However, these photocatalysts are usually suspended in water, limiting their practical application by accumulating and reusing photocatalyst nanopowder from a suspension.…”

Efficient and Facile Synthetic Route of MoO3:MoS2 Hybrid Thin Layer via Oxidative Reaction of MoS2 Nanoflakes

“…Its stable structure consists of hexagonal layers co-bonded via Van der Waals forces, and each layer has covalent bonds between Mo and S (S-Mo-S). The tunable bandgap energy from 1.2 eV for bulk MoS 2 material to 1.8 eV in monolayer and the transition of the bandgap from indirect to direct bandgap has generated massive attention in exploring MoS 2 for various applications, such as hydrogen production [4][5][6], optoelectronic [7,8], lubrication [9], batteries [10], photocatalysis [11], and transistors [12].…”