Recyclable Ni₃S₄Nanocatalyst for Hydrogenation of Nitroarenes

Abstract

The synthesis of surface‐clean nanoparticles of Ni3S4, which is a rare phase of nickel sulphides, is described. Nanoparticles were synthesized in a single step via hexamethyldisilazane (HMDS) –assisted method using NiCl2 and thiourea as starting materials. This synthetic method yielded phase pure, spherical Ni3S4 nanoparticles of mean size 17 ± 4 nm having clean surfaces. The nanoparticles were characterized thoroughly by data obtained from Powder X‐ray diffraction (PXRD), Fourier‐transform infrared spectra (FT‐IR), Energy dispersive X‐ray analysis (EDAX) and Transmission electron microscopy (TEM) analyses. Since newly produced Ni3S4 nanoparticles in our reaction had exposed surfaces, the catalytic behaviour of these particles was assessed by using it as a catalyst in the reduction reaction of aromatic nitro groups. We have demonstrated Ni3S4 nanoparticle as a versatile catalyst for the nitro hydrogenation of both activated and deactivated nitrobenzenes using hydrazine as a hydrogen source to yield corresponding amines in high yield (∼90 %). The heterogeneous catalyst, Ni3S4 nanoparticles was recycled more than ten times without any change in its activity. We have ascribed the enhanced catalytic activity of these Ni3S4 nanoparticles to their clean surfaces without any surfactant molecules around them.

Reduction of Nitro Compounds Using 3d-Non-Noble Metal Catalysts

“…Recently, Muralidharan and co-workers reported a Ni 3 S 4 nanocatalyst for the nitro reduction in the presence of 8 equiv of hydrazine . It was synthesized by simply reacting NiCl 2 with thiourea and HN­(SiMe 3 ) 2 at 130 °C.…”

“…Recently, Muralidharan and co-workers reported a Ni 3 S 4 nanocatalyst for the nitro reduction in the presence of 8 equiv of hydrazine. 305 It was synthesized by simply reacting NiCl 2 with thiourea and HN(SiMe 3 ) 2 at 130 °C. The purified material was able to hydrogenate nitrobenzene and derivatives in ethanol at 125 °C with N 2 H 4 at 1 mol % loading.…”

Bifunctional hexagonal Ni/NiO nanostructures: influence of the core–shell phase on magnetism, electrochemical sensing of serotonin, and catalytic reduction of 4-nitrophenol

“…This increase in the peak intensity corresponded to 4-aminophenol at 298 nm, which is in good agreement with the literature. 37,38 Catalytic reduction started with the formation of an intermediate (4-nitrophenolate ions), which turned a mild-yellow solution to dark-yellow. Adsorption of nitrophenolate on the nanoparticle surface followed by hydrogen transfer to catalyst facilitated reduction of the nitro group to an amino group.…”

Solution Combustion Synthesis of NiS‐NiS2 Nanoparticles for Catalytic Reduction of Nitro Aromatics

“…Though the surface area is found to be very less, nickel sulfide prepared by combustion method was found to exhibit good catalytic activity towards reduction of nitrophenol in the ChemistrySelect present work which is in support of the earlier reports. [17] Factors contributing to this enhanced activity may be arising from larger pore diameter that supports the faster entry and contact of reactant molecules with large number of dispersed active catalytic sites and easy removal of products. Also, direct synthesis of the catalyst without using any surfactant leaves the surface clean and structure sensitive.…”

“…[2,3,12,[14][15][16] In the context of catalytic reduction of 4-NP, the use of nanoparticles of nickel sulfide and its composites is reported by reasonably good number of groups with promising activities. [6,8,13,14,17,18] The syntheses methods used in these studies are relatively laborious involving multiple steps, time consuming and make use of expensive instrumentation and chemicals. To cite a few, nitrophenol reduction with Ni 7 S 6 is brought about using hydrogen at high temperature and pressure.…”