Hydrogenation Of 4-nitrophenol Research Articles

Highly Efficient Electrospun Silver Decorated Graphene Oxide Nanocomposites on Poly(vinylidene fluoride) (PVDF@GO-Ag) Hybrid Membrane for Reduction of 4-Nitrophenol.

Graphene oxide-silver poly(vinylidene fluoride) membranes (PVDF@GO-Ag) were successfully synthesized by the electrospinning method, which exhibited a high catalytic activity using the hydrogenation of 4-nitrophenol (4-NP) as a model reaction in a batch reaction study. The hybrid membranes doped with 1 wt% GO and 2 wt% Ag (PVDF-1-2) exhibited the most desired performance for the catalytic reduction of 4-NP. Importantly, PVDF-1-2 exhibited excellent cycling stability in 10 catalytic cycle tests and was highly amenable to separation. This property effectively addresses the significant challenges associated with the practical application of nanocatalysts. Furthermore, density-functional theory (DFT) calculations have demonstrated that the GO-Ag nanocomposites exhibit the strongest adsorption capacity for 4-NP- when a specific ratio of GO and Ag is achieved, accompanied by the loading of Ag nanoclusters onto GO. Additionally, the study demonstrated that an increase in temperature significantly accelerated the reaction rate, in line with the van't Hoff rule. This study provides an effective and environmentally friendly solution for the treatment of 4-NP in wastewater.

Pd/N-doped carbon dots@dendritic mesoporous silica nanospheres: A highly efficient catalyst for the hydrogenation of 4-nitrophenol

Pd/N-doped carbon dots@dendritic mesoporous silica nanospheres: A highly efficient catalyst for the hydrogenation of 4-nitrophenol

Insights into the Catalytic Performance of Multichannel Ceramic Catalytic Membrane in Liquid-Phase p-Nitrophenol Hydrogenation: Role of Storage Method

Insights into the Catalytic Performance of Multichannel Ceramic Catalytic Membrane in Liquid-Phase <i>p</i>-Nitrophenol Hydrogenation: Role of Storage Method

Ultrafine CoNi alloy nanoparticles anchored on surface-roughened halloysite nanotubes for highly efficient catalytic hydrogenation of 4-nitrophenol

The hydrogenation of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) is an effective and cost-competitive procedure to change waste into valuables. With the purpose of designing efficient and green catalysts to convert 4-NP, we adopt halloysite nanotubes (HNTs), a resource-rich and eco-friendly clay mineral material, as CoNi alloy nanoparticles support in this study. The HNTs used have been increased the surface roughness (defined as rHNTs) through the etching process. Thereafter, a series of ultrafine CoNi alloy nanoparticles (1.2 ∼ 1.4 nm) anchored onto rHNTs (CoxNi1-x/rHNTs, where x represents the molar percentage of Co to total metal elements) are successfully synthesized via a simple one-pot approach. Benefitting from the positive synergy of Co and Ni bimetals and the powerful metal-support interaction, Co0.7Ni0.3/rHNTs catalyst (8.55 wt% total actual metal loading) exhibits the best catalytic performance for 4-NP degradation with a conversion efficiency of 99 % within 4 min at 298 K, and meanwhile a high turnover frequency (TOF) of 1.16 × 10-2 mmol mg−1 min−1 is achieved with the rate constant of 1.09 min−1. Of note, Co0.7Ni0.3/rHNTs also show excellent degradation performance towards two other nitrophenol isomers (2-nitrophenol and 3-nitrophenol).

Bimetallic PdCo and PdNi Nanoparticles Supported on Covalent Organic Frameworks as Catalysts for the Hydrogenation of 4-Nitrophenol

Bimetallic PdCo and PdNi Nanoparticles Supported on Covalent Organic Frameworks as Catalysts for the Hydrogenation of 4-Nitrophenol

Bimetallic CuPd micro-rods: synthesis and catalytic hydrogenation performance

The fabrication of an efficient catalyst for the hydrogenation of 4-nitrophenol is of major significance for both environmental protection and industrial resources. Here, bimetallic CuPd micro-nano structures with string, rod, and polyhedron can be fabricated by using nicotinic acid. The optimisation of synthesis was investigated by modulating the ratio of precursors and reaction conditions, and the correlation between catalytic properties and the morphology of materials was also estimated. Among them, CuPd microrods synthesised by 0.20 M nicotinic acid exhibited the highest catalytic activity in the hydrogenation reaction of 4-NP by sodium borohydride. The evaluation of reusability demonstrated that the catalytic efficiency maintained a conversion yield of 98% without significant loss of performance. The synergistic effect of bimetallic catalysts promoted efficient performance in hydrogenation, which will arouse the extensive development of bimetallic catalysts and serve in catalysis efficiently.

Engineering of uniform dispersed Ni nanoparticles supported on carbon nanosheets for reduction of Nitroarenes to Aminoarenes

Facile synthesis of uniform supported metal catalysts is of great significance yet remains challenging for sustainable catalysis. Herein, a nanopore confinement strategy is developed to efficiently anchor metal ions in suitably sized polymer nanopores via strong coordinate bonds and ensure successful fabrication of uniform carbon-supported metal nanoparticles. Specifically, Ni2+-coordinated polydopamine (PDA) mesoporous layer was coated on GO nanosheets for the confinement of the nickel atoms (GO@PDA-Ni-x, x means pore size of PDA layer), resulting Ni@C-x nanosheets catalysts with uniformly dispersed Ni nanoparticles after pyrolysis in H2/Ar atmosphere. Characterization methods including SEM, TEM, and XPS reveal the intrinsic formation mechanism and physicochemical details. In the catalytic reaction of NaBH4-mediated hydrogenation of 4-nitrophenol (4-NP), the obtained Ni/C-10 exhibits exceptional catalytic performance with a rapid rate constant (0.686 min−1), outperforming many previously reported metal catalysts. Moreover, the catalytic activity remains almost unchanged after being recycled five times, proving the prominent stability. This work opens up an innovative avenue for rational design and synthesis of supported catalysts with controllable size for broad catalytic applications.

Schiff Base Functionalized Cellulose: Towards Strong Support-Cobalt Nanoparticles Interactions for High Catalytic Performances.

A new hybrid catalyst consisting of cobalt nanoparticles immobilized onto cellulose was developed. The cellulosic matrix is derived from date palm biomass waste, which was oxidized by sodium periodate to yield dialdehyde and was further derivatized by grafting orthoaminophenol as a metal ion complexing agent. The new hybrid catalyst was characterized by FT-IR, solid-state NMR, XRD, SEM, TEM, ICP, and XPS. The catalytic potential of the nanocatalyst was then evaluated in the catalytic hydrogenation of 4-nitrophenol to 4-aminophenol under mild experimental conditions in aqueous medium in the presence of NaBH4 at room temperature. The reaction achieved complete conversion within a short period of 7 min. The rate constant was calculated to be K = 8.7 × 10-3 s-1. The catalyst was recycled for eight cycles. Furthermore, we explored the application of the same catalyst for the hydrogenation of cinnamaldehyde using dihydrogen under different reaction conditions. The results obtained were highly promising, exhibiting both high conversion and excellent selectivity in cinnamyl alcohol.

Three-Dimensionally Nanometallic Superstructure Synthesized via a Single-Particle Soft-Enveloping Strategy.

Three-dimensionally (3D) integrated metallic nanomaterials composed of two or more different types of nanostructures make up a class of advanced materials due to the multidimensional and synergistic effects between different components. However, designing and synthesizing intricate, well-defined metallic 3D nanomaterials remain great challenges. Here, a novel single-particle soft-enveloping strategy using a core-shell Au NP@mSiO2 particle as a template was proposed to synthesize 3D nanomaterials, namely, a Au nanoparticle@center-radial nanorod-Au-Pt nanoparticle (Au NP@NR-NP-Pt NP) superstructure. Taking advantage of the excellent plasmonic properties of Au NP@NR-NP by the synergistic plasmonic coupling of the outer Au NPs and inner Au nanorods, we can enhance the catalytic performance for 4-nitrophenol hydrogenation using Au NP@NR-NP-Pt NP as a photocatalyst with plasmon-excited hot electrons from Au NP@NR-NP under light irradiation, which is 2.76 times higher than in the dark. This process opens a door for the design of a new generation of 3D metallic nanomaterials for different fields.

Extreme environmental micro-plasma electrolyte oxidation induced defect-rich Au nanoparticles catalyst improving the nitrophenol hydrogenation reaction

The defect-rich Au nanoparticles (NPs) catalyst on Mg surface was prepared by the micro-plasma electrolyte oxidation (MPEO) utilizing liquid nitrogen as the cooling medium. MPEO is a high-temperature plasma oxidation process that decomposes the [AuCl4]-precursor salt to form metastable state Au NPs. The rapid quenching effect of liquid nitrogen occurs during this non-equilibrium process and generates numerous defects on the Au NPs, thereby altering their electronic state. Consequently, the catalytic performance of this Au/MgO catalyst was outstanding, exceeding that of the sample prepared without using liquid nitrogen. This finding indicates that the harsh environment plays a crucial role in producing defect-rich Au NPs and improving the catalytic efficiency.

Iron-doped copper-cobalt sulfide nano-box derived from ZIF-67 as a high-efficiency heterogeneous catalyst for hydrogenation of 4-nitrophenol

4-Nitrophenol (4-NP) is a highly toxic substance commonly found in industrial and agricultural wastewater. However, precious metal materials commonly used for catalytic degradation of 4-NP are scarce and expensive. Therefore, we have prepared an iron-doped copper cobalt sulfide nano box (Fe@CuCo-SNBs) using ZIF-67 as a sacrificial template, which contains rich heterostructures. This material is used to catalyze the degradation of toxic 4-NP to 4-AP (4-Aminophenol, a widely used chemical intermediate), showing extremely high catalytic activity. The pseudo-first order reaction kinetic constant is 2.43 min−1, and the specific activity is 0.5 μmol·mg−1·min−1, which is higher than many noble metal catalysts, showing a good application prospect.

A Novel Molten Salt Mediated Synthesis of Mesoporous Metal Oxides with High Crystallization.

The controlled synthesis of mesoporous metal oxides remains a great challenge because the uncontrolled assembly process and high-temperature crystallization can easily destroy the mesostructure. Herein, we develop a facile, versatile, low-cost, and controllable molten salt assisted assembly strategy to synthesize mesoporous metal oxides (e.g., CeO2, ZrO2, SnO2, Li2TiO3) with high surface area (115-155 m2/g) and uniform mesopore size (3.0 nm). We find this molten salt mediated assembly enables the desolvation of the precursors and forms bare metal ions, enhances their coordination interaction with the surfactant, and promotes their assembly into a mesostructure. Furthermore, the molten salt assisted crystallization process can lower the collision probability of the target metal atom, inhibit its further growth into large crystals, and achieve a well-maintained mesostructure with high crystallization. Furthermore, this method can be expanded to synthesize various structured mesoporous metal oxides, including hollow spheres, nanotubes, and nanosheets by introducing the carbon template. The obtained mesoporous CeO2 microspheres loaded with Cu species exhibit excellent antibacterial performance and superior catalytic activity for the hydrogenation of nitrophenol with high conversion and cycling stability.

Anchoring of Pd nanoparticles over amines grafted 3D TiO2 catalyst for the improved selective hydrogenation of 4-nitrophenol

The fabrication of small Pd nanoparticles (NPs) anchored on titanium dioxide (TiO2) supports remains a great challenge due to its high surface energy. Herein, flower-like three dimensional (3D) TiO2 microstructures assembled from needle flakes are fabricated thru a facile evaporation-induced assisted hydrothermal method, and then modified with amines group (3D-TiO2-NH2). Small and uniform dispersed Pd nanoparticles were anchored on the surface of 3D-TiO2-NH2 supports using polyol reduction method. Remarkably, the obtained 3D-TiO2-NH2 supported Pd-based catalyst (Pd@3D-TiO2-NH2) demonstrated an optimal 4-NP catalytic hydrogenation efficiency (k = 1.09 min−1), which is 1.56 and 3.52 times superior than that of the Pd@3D-TiO2 (k = 0.699 min−1) and Pd@TiO2–P25 (k = 0.31 min−1) catalysts, respectively. In-depth investigation of the structure-property relationship by SEM, XRD, N2 adsorption-desorption isotherm, TEM, XPS, CO chemisorption and CO-FTIR reveal that the optimal catalytic hydrogenation activity of Pd@3D-TiO2-NH2 can be credited to its 3D hierarchical structure (interconnected needle flakes) and the amines group existing on the surface of flower-like three dimensional hierarchical TiO2, which control the Pd particles size (2.7 nm) and uniform dispersion (43.5%) to generate more surface active Pd0 entities over Pd@3D-TiO2-NH2.

Utilization of Magonia pubescens extracts in the synthesis of rhodium NPs on Fe3O4@MgO support: A novel catalyst for 4-nitrophenol hydrogenation

This study reports the development of three distinct nanoparticulate catalysts, each comprising a biosynthesized Fe3O4 nanoparticle magnetic core with an average diameter of 17 nm, showcasing superparamagnetic behavior. This magnetic core was further encased in a spherical magnesium oxide (MgO) layer through a bio-inspired strategy, leading to the Fe3O4@MgO support structure. Rhodium (Rh) nanoparticles, with diameters between 1.0 and 1.5 nm, were then fabricated to act as the main catalytic entities. These were subsequently affixed to the Fe3O4@MgO support, yielding Fe3O4@MgO-Rh, using three distinct methodologies. Remarkably, the bio-inspired processes employed for the creation of Fe3O4@MgO-Rh harnessed the infusion and extract from Magonia pubescens A St. Hil leaves, colloquially termed “Timbó”. These natural extracts played dual roles as reducing and stabilizing agents during the catalyst generation, leading to three variants: CI, CW, and CS. Comprehensive characterization of these catalysts was achieved using XPS, TEM, EDS, and VSM techniques. The ensuing evaluation involved the hydrogenation of 4-nitrophenol, which served to assess the efficiency and resilience of the bio-inspired catalysts vis-à-vis conventionally-produced counterparts. Notably, under benign conditions of a molecular H2 atmosphere (an ecologically sound hydrogen atom source) and moderate temperatures (60 °C), conversion rates exceeding 97 % were consistently observed for the substrate within a time frame of 0 to 15 min. For a more granular comparison of efficiency among the rhodium-centric catalysts, Turnover Frequency (TOF) and Total Turnover Number (TTON) computations were undertaken. Herein, the CI catalyst, originating from infusion, displayed a TTON value of 1263.24, underscoring its preeminence in 4-NF hydrogenation reactions. This was closely trailed by the CS catalyst, which boasted a TTON of 873.63, synthesized with a commercial surfactant.

Ag nanoparticles decorated on Co3O4‐C derived from ZIF‐67: a recyclable catalyst for highly efficient reduction of nitrophenols

AbstractSilver‐based nanostructured composites as effective and stable catalysts were successfully designed as the catalyst to reduce the nitrophenols in aqueous solution at room temperature in the presence of NaBH4. The Co3O4‐C composites with regular morphology and adjustable components derived from ZIF‐67 in an air atmosphere at various temperatures (270, 300, and 350 °C) were chosen as a favorable platform to support silver nanoparticles. The acquired silver‐based nanocatalyst (Ag/Co3O4‐C) exhibited excellent catalytic performance towards the hydrogenation of nitrophenols (2‐NP, 3‐NP, and 4‐NP). The calculated rate constant (Kapp) towards the reduction of 4‐NP followed the order: Ag/Co3O4‐C‐300 (0.70 min−1)&gt;Ag/Co3O4‐C‐270 (0.58 min−1)&gt;Ag/Co3O4‐C‐350 (0.46 min−1). Ag/Co3O4‐C‐300 possessed the highest catalytic activity with no induction time during the reaction. What is more, Ag/Co3O4‐C‐300 could reduce 2‐NP and 3‐NP with the rate constant of 0.936 min−1 and 0.391 min−1, respectively. The catalytic activity was higher that many other metal‐based nanocomposites. The excellent catalytic performance was mainly attributed to the abundant active sites on the surface, and the interfacial synergistic effect between Ag and Co3O4‐C, which had a potential driving force for the hydrogenation reaction. In addition, the catalyst remained active even after recirculation experiments. The Ag‐based nanocomposites can be expected to be applied in industrial applications.

One-pot mechanochemical hydrogenation and acetylation of 4-nitrophenol to 4-aminophenol and paracetamol

The mechanochemical hydrogenation of 4-nitrophenol was examined in a ball mill reactor.

Amino-tethered Ni3S2/MoS2 heterojunction for coupling electrochemical 5-hydroxymethylfurfural oxidation with 4-nitrophenol hydrogenation

Continuous paired electrochemical refining consists of two compartments: anodic 5-hydroxymethylfurfural oxidation (right-hand side) and cathodic 4-nitrophenol hydrogenation (left-hand side).

Core–shell magnetic mesoporous 3-aminophenol–formaldehyde resin microspheres with rich functional groups via interface co-assembly and polymerization

Core–shell magnetic mesoporous 3-aminophenol–formaldehyde resin microspheres were designed to immobilize Au nanoparticles for use as magnetically separable heterogeneous catalysts for the efficient hydrogenation of 4-nitrophenol at room temperature.

Electronic modulation induced by oxygen vacancy creating in copper oxides toward accelerated hydrogenation kinetics of nitroaromatics

The development of advanced catalysts is of vital importance for chemical production, and vacancy engineering represents an effective approach to improve the overall catalytical activities by modulating their structural characters. Herein, a series of oxygen-vacancy-functionalized copper oxides were effectively prepared through a hydrothermal-oxidative tandem process. The optimized CuO-S30 catalyst shows an exceptionally-improved catalytical performance for the selective hydrogenation of 4-nitrophenol (4-NP) with good reusability. With the assistance of theoretical simulation, the exceptional activity can be attributed to the electronic modulation induced by oxygen vacancies in CuO-S30, which could not only facilitate the trapping of the reactants on the positively charged Cu sites, but also promote the electron transfer during the hydrogenation process. This study offers a facile and environmentally friendly strategy for electronic property modulation in metal oxides by oxygen vacancies construction, which can be further extended to other advanced catalysts with outstanding catalytic properties.

Novel, Biosynthesis of Palladium Nanoparticles using Strychnos Potatorum Polysaccharide as a Green sustainable approach; and their effective Catalytic Hydrogenation of 4-Nitrophenol

In the current study, we successfully used strychnos potatorum polysaccharide through autoclaving to synthesize palladium nanoparticles in a green, sustainable process. These polysaccharide act as a stabilizing, capping, and reducing agent. It also used various analytical characterizations, including UV–Visible spectroscopy, FT-IR spectroscopy, X-Ray diffraction (XRD), Scanning electron microscopy (FE-SEM), EDAX, and X-ray photoelectron spectroscopy (XPS), TEM and gel permeation chromatography (GPC) are used to analyze biosynthesized pallidum nanoparticles (PdNPs). The surface plasmon resonance (SPR) band at 276 nm and UV–visible spectroscopy revealed the presence of the generated PdNPs. The XRD data show that PdNPs have crystalline behavior and a pristine face-centered cubic (FCC) structure. The PdNPs were successfully developed by catalytic reduction of 4-nitrophenol (4-NP). The catalytic activity and reusability of the environmentally friendly PdNPs catalyst were demonstrated by achieving a remarkable transformation of 95 % nitrophenol to 4-aminophenol after five cycles. The reaction rate constant (k) for the degradation of 4-nitrophenol (4-NP) using SP-PdNPs as a catalyst is 0.1201 min−1 and R2 0.9867, with a normalized rate constant of (Knor = K/m) of 7.206 s−1 mM−1. These findings provide fundamental knowledge of the catalytic process governing the hydrogenation of p-nitrophenol, which will help designers of effective catalysts. An innovative and affordable technique for creating PdNPs that are environmentally acceptable and can be utilized as effective catalysts in environmental applications is the use of strychnos potatorum gum polysaccharide. The green-synthesized PdNPs can be used for pollutant remediation, including pharmaceutical, domestic, heavy metal, industrial, and pesticide pollutants.