Controlled Synthesis of Palladium Nanocubes as an Efficient Nanocatalyst for Suzuki–Miyaura Cross-Coupling and Reduction of p-Nitrophenol

Abstract

Anisotropic nanocatalysts have attracted considerable attention in comparison to bulk/nanocatalysts for their enhanced activity and reactivity. The demand toward anisotropic palladium (Pd) nanostructures has increased rapidly in the field of catalysis. Pd is a well-known active catalyst for several carbon–carbon (C–C) cross-coupling reactions; among them, the Suzuki–Miyaura cross-coupling reaction is one of the most versatile and dominant methods for constructing the extraordinarily useful unsymmetrical biaryls and also for hydrogenation of organic contaminants like p-nitrophenol (p-NP). This paper provides a brief explanation about the controlled synthesis, characterization, and catalytic activity of well-defined palladium nanocubes (Pd NCs) prepared by a seed-mediated method. The synthesized monodispersed Pd NCs were characterized by spectroscopic and microscopic tools such as UV–visible, XRD, FESEM, HRTEM, and EDS analyses. Pd NCs proved as an efficient catalyst for Suzuki–Miyaura cross-coupling reactions and p-NP reduction. The catalyst shows enhanced activity, greater stability, and higher selectivity with remarkable recyclability up to 92% for five consecutive cycles. The catalytic performance of the synthesized Pd NCs was also studied in the reduction of the organic contaminant p-NP, which showed an excellent performance screening of 99% conversion in 6 min.

CoFe Nanoparticle-Decorated Reduced Graphene Oxide for the Highly Efficient Reduction of 4-Nitrophenol

“…Due to the highly toxic, carcinogenic, and teratogenic properties, 4-NP is well-known as one kind of the “priority pollutants” . Many kinds of catalysts have been developed for the catalytic degradation of 4-NP to 4AP, including Pd–Ni nanowires, Pt–Fe 3 O 4 , Pt–Cu bimetallic NPs, Au-Silica, Pd cubes, Au–SnO 2 , and so on. ,− Therefore, the catalytic properties of the CoFe/RGO nanocomposites were evaluated by the reduction of 4-NP to 4-AP. The reaction kinetic parameters were determined from the time-dependent spectra of the solution.…”

Green chemistry and first-principles theory enhance catalysis: synthesis and 6-fold catalytic activity increase of sub-5 nm Pd and Pt@Pd nanocubes

“…Pd nanocubes with dimension above 100 nm proved to be an efficient catalyst for cross-coupling reactions and for nitrophenol reduction whilst providing greater stability and higher selectivity with enhanced recyclability. 20 Also in the attempt to find alternatives to fossil fuels by developing viable fuel cells, the surface structure of Pd catalysts is a critical point to achieve highly improved efficiency and market performance requirements for direct formic acid fuel cells. 21,22 Indeed, from the studies on single-crystal Pd electrodes, the effect of surface structure has been elucidated, showing that the current density reaches a maximum value for Pd (100).…”

“…Alternatively, the use of green bio-reductants, which also act as stabilizers, has been proposed as an economical and environmental solution but reproducibility issues and a high variability in the bio-extract composition and consequent low catalytic activity hampered their use. 20,24 In this framework, solution-phase syntheses for the formation of metal particles with sizes below 7 nm with narrow size and shape distributions and a high yield of usable material are challenging. A limiting factor of many synthetic protocols is the use of various surfactants, polymers, and hard templates, [25][26][27][28] which can significantly alter the properties of the material 21,24,[29][30][31] and are difficult to remove after synthesis.…”

“…Alternatively, the use of green bio-reductants, which also act as stabilizers, has been proposed as an economical and environmental solution but reproducibility issues and a high variability in the bio-extract composition and consequent low catalytic activity hampered their use. 20,24…”

One-step synthesis of PdCu@Ti3C2 with high catalytic activity in the Suzuki–Miyaura coupling reaction

“…[1][2][3][4][5] The use of 2D materials as carriers can effectively reduce the amount of Pd, a high-cost noble metal catalyst commonly used in C-C coupling reactions. [6][7][8][9][10][11][12] However, the most widely used 2D substrate, graphene oxide (GO), cannot have both excellent electrical conductivity and hydrophilic properties simultaneously, and this limits the application of GO carriers. There are other problems with the use of GO as a substrate to prepare catalysts for C-C coupling reactions: (1) it requires surface functionalization 1,2 or compounding with other materials 4 to improve its charge transfer capability, making the catalyst preparation process more complicated; (2) the current catalysts have high catalytic activity only in organic solvents, which may have some environmental impact and loss of product; [1][2][3][4][5] and (3) the high Pd content in the catalysts leads to high costs.…”