Facet-dependent Catalysis of CuNi Nanocatalysts toward 4–Nitrophenol Reduction Reaction

ABSTRACTWe report a facile method to fabricate CuNi nano-octahedra and nanocubes using a colloidal synthesis approach. The CuNi nanocrystals terminated with exclusive crystallographic facets were controlled and achieved by a group of synergetic capping ligands in a hot solution system. Specifically, the growth of {111}-bounded CuNi nano-octahedra is derived by a thermodynamic control, whereas the generation of {100}-terminated CuNi nanocubes is steered by a kinetic capping of chloride. Using a reduction of 4-nitrophenol with sodium borohydride as a model reaction, CuNi nano-octahedra and nanocubes demonstrated a strong facet-dependence due to their different surface energies although both exhibited remarkable catalytic activity with the high rate constant over mass (k/m). A kinetic study indicated that this is a pseudo first-order reaction with an excess of sodium borohydride. CuNi nanocubes as the catalysts showed better catalytic performance (k/m = 385 s-1•g-1) than the CuNi nano-octahedra (k/m = 120 s-1•g-1), indicating that 4-nitrophenol and hydrogen were adsorbed on the {100} facets with their molecules parallel to the surface much easier than those on {111} facets.

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Ruthenium Supported on Ionically Cross-linked Chitosan-Carrageenan Hybrid MnFe2O4 Catalysts for 4-Nitrophenol Reduction

Catalysts ◽

10.3390/catal9030254 ◽

2019 ◽

Vol 9 (3) ◽

pp. 254 ◽

Cited By ~ 3

Author(s):

Kin Hong Liew ◽

Tian Khoon Lee ◽

Mohd Ambar Yarmo ◽

Kee Shyuan Loh ◽

Andreia F. Peixoto ◽

...

Keyword(s):

Catalytic Activity ◽

Electrostatic Interactions ◽

Catalytic Performance ◽

Reduction Reaction ◽

Ru Nanoparticles ◽

Nitrophenol Reduction ◽

Active Metal ◽

Wide Range ◽

Mnfe2o4 Nanoparticles ◽

Superparamagnetic Properties

Herein, we report a facile procedure to synthesize the hybrid magnetic catalyst (Ru@CS-CR@Mn) using ruthenium (Ru) supported on ionically cross-linked chitosan-carrageenan (CS-CR) and manganese ferrite (MnFe2O4) nanoparticles with excellent catalytic activity. The ionic gelation of CS-CR is acting as a protecting layer to promote the encapsulation of MnFe2O4 and Ru nanoparticles by electrostatic interactions. The presence of an active metal and a CS-CR layer on the as-prepared Ru@CS-CR@Mn catalyst was well determined by a series of physicochemical analyses. Subsequently, the catalytic performances of the Ru@CS-CR@Mn catalysts were further examined in the 4-nitrophenol (4-NP) reduction reaction in the presence of sodium borohydride (reducing agent) at ambient temperature. The Ru@CS-CR@Mn catalyst performed excellent catalytic activity in the 4-NP reduction, with a turnover frequency (TOF) values of 925 h−1 and rate constant (k) of 0.078 s−1. It is worth to mentioning that the Ru@CS-CR@Mn catalyst can be recycled and reused up to at least ten consecutive cycles in the 4-NP reduction with consistency in catalytic performance. The Ru@CS-CR@Mn catalyst is particularly attractive as a catalyst due to its superior catalytic activity and superparamagnetic properties for easy separation. We foresee this catalyst having high potential to be extended in a wide range of chemistry applications.

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Size-Controlled Synthesis of CuNi Nano-Octahedra and Their Catalytic Performance towards 4-Nitrophenol Reduction Reaction

MRS Advances ◽

10.1557/adv.2019.47 ◽

2019 ◽

Vol 4 (5-6) ◽

pp. 263-269 ◽

Cited By ~ 1

Author(s):

Can Li ◽

Yiliang Luan ◽

Bo Zhao ◽

Amar Kumbhar ◽

Jiye Fang

Keyword(s):

Catalytic Performance ◽

Reduction Reaction ◽

Controlled Synthesis ◽

Solution Approach ◽

Size Dependent ◽

Surface Areas ◽

Nitrophenol Reduction ◽

Crystallographic Planes ◽

Size Controlled ◽

Octahedral Nanocrystals

ABSTRACTIn this work, we demonstrate a size-controlled synthesis of CuNi octahedral nanocrystals (NCs) using a hot colloidal solution approach. Two different sizes of CuNi nano-octahedra are chosen and investigated. It is determined that the reagent concentration remarkably plays a key role in the formation of the size-defined CuNi octahedral NCs. In terms of the reduction of 4-nitrophenol (4-NP), it uncovers that the obtained CuNi octahedral NCs (in both sizes) exhibit higher catalytic activity than those of CuNi spherical NCs reported previously. It further indicates that the catalytic performance is strongly size-dependent due to their devise specific surface areas of the exposed crystallographic planes.

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The catalytic evaluation of in situ grown Pd nanoparticles on the surface of Fe3O4@dextran particles in the p-nitrophenol reduction reaction

RSC Advances ◽

10.1039/c4ra16440g ◽

2015 ◽

Vol 5 (11) ◽

pp. 8289-8296 ◽

Cited By ~ 25

Author(s):

Luciano R. S. Lara ◽

Alexandre D. Zottis ◽

Welman C. Elias ◽

Deonildo Faggion ◽

Carlos Eduardo Maduro de Campos ◽

...

Keyword(s):

Catalytic Activity ◽

Sodium Borohydride ◽

Pd Nanoparticles ◽

Reduction Reaction ◽

Natural Polymer ◽

Activity Evaluation ◽

Nitrophenol Reduction

We report the catalytic activity evaluation of in situ grown Pd nanoparticles on the surface of superparamagnetic Fe3O4 particles coated with the natural polymer dextran, in the reduction of p-nitrophenol (Nip), in water, by sodium borohydride.

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Tuning the Covering on Gold Surfaces by Grafting Amino-Aryl Films Functionalized with Fe(II) Phthalocyanine: Performance on the Electrocatalysis of Oxygen Reduction

Molecules ◽

10.3390/molecules26061631 ◽

2021 ◽

Vol 26 (6) ◽

pp. 1631

Author(s):

Camila F. Olguín ◽

Nicolás Agurto ◽

Carlos P. Silva ◽

Carolina P. Candia ◽

Mireya Santander-Nelli ◽

...

Keyword(s):

Oxygen Reduction ◽

Diazonium Salt ◽

Gold Surface ◽

Catalytic Performance ◽

Reduction Reaction ◽

Salt Reduction ◽

Surface Electrodes ◽

Custom Made ◽

Aryl Diazonium Salt ◽

Inorganic Molecules

Current selective modification methods, coupled with functionalization through organic or inorganic molecules, are crucial for designing and constructing custom-made molecular materials that act as electroactive interfaces. A versatile method for derivatizing surfaces is through an aryl diazonium salt reduction reaction (DSRR). A prominent feature of this strategy is that it can be carried out on various materials. Using the DSRR, we modified gold surface electrodes with 4-aminebenzene from 4-nitrobenzenediazonium tetrafluoroborate (NBTF), regulating the deposited mass of the aryl film to achieve covering control on the electrode surface. We got different degrees of covering: monolayer, intermediate, and multilayer. Afterwards, the ArNO2 end groups were electrochemically reduced to ArNH2 and functionalized with Fe(II)-Phthalocyanine to study the catalytic performance for the oxygen reduction reaction (ORR). The thickness of the electrode covering determines its response in front of ORR. Interestingly, the experimental results showed that an intermediate covering film presents a better electrocatalytic response for ORR, driving the reaction by a four-electron pathway.

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Fe3 Cluster Anchored on the C2N Monolayer for Efficient Electrochemical Nitrogen Fixation

Catalysts ◽

10.3390/catal10090974 ◽

2020 ◽

Vol 10 (9) ◽

pp. 974

Author(s):

Bing Han ◽

Haihong Meng ◽

Fengyu Li ◽

Jingxiang Zhao

Keyword(s):

Nitrogen Fixation ◽

First Principles ◽

Catalytic Performance ◽

Reduction Reaction ◽

First Principles Calculations ◽

Ammonia Gas ◽

Nitrogen Reduction ◽

Single Cluster ◽

Excellent Catalytic Performance ◽

Production Of Ammonia

Under the current double challenge of energy and the environment, an effective nitrogen reduction reaction (NRR) has become a very urgent need. However, the largest production of ammonia gas today is carried out by the Haber–Bosch process, which has many disadvantages, among which energy consumption and air pollution are typical. As the best alternative procedure, electrochemistry has received extensive attention. In this paper, a catalyst loaded with Fe3 clusters on the two-dimensional material C2N (Fe3@C2N) is proposed to achieve effective electrochemical NRR, and our first-principles calculations reveal that the stable Fe3@C2N exhibits excellent catalytic performance for electrochemical nitrogen fixation with a limiting potential of 0.57 eV, while also suppressing the major competing hydrogen evolution reaction. Our findings will open a new door for the development of non-precious single-cluster catalysts for effective nitrogen reduction reactions.

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Electro-catalysis of carbon black or titanium sub-oxide supported Pd–Gd towards formic acid electro-oxidation

RSC Advances ◽

10.1039/c6ra13097f ◽

2016 ◽

Vol 6 (73) ◽

pp. 68989-68996 ◽

Cited By ~ 13

Author(s):

Nan He ◽

Chuanguang Qin ◽

Rumin Wang ◽

Shuhui Ma ◽

Yi Wang ◽

...

Keyword(s):

Aqueous Solution ◽

Carbon Black ◽

Formic Acid ◽

Sodium Borohydride ◽

Weight Percent ◽

Reduction Reaction ◽

Simultaneous Reduction ◽

Electro Catalysis ◽

Electro Oxidation ◽

Supported Pd

Carbon black supported Pd–Gd catalysts (Pd–xGd/C, x is weight percent in catalyst) with different amounts of Gd were prepared by a simultaneous reduction reaction with sodium borohydride in aqueous solution.

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Enhanced Electrocatalytic Activity and Stability toward the Oxygen Reduction Reaction with Unprotected Pt Nanoclusters

Nanomaterials ◽

10.3390/nano8110955 ◽

2018 ◽

Vol 8 (11) ◽

pp. 955 ◽

Cited By ~ 3

Author(s):

Jing Liu ◽

Jiao Yin ◽

Bo Feng ◽

Tao Xu ◽

Fu Wang

Keyword(s):

Carbon Nanotubes ◽

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Specific Activity ◽

Catalytic Performance ◽

Reduction Reaction ◽

Top Down ◽

Methanol Tolerance ◽

Pt Nanoclusters ◽

Mass Activity

The Pt particles within diameters of 1–3 nm known as Pt nanoclusters (NCs) are widely considered to be satisfactory oxygen reduction reaction (ORR) catalysts due to higher electrocatalytic performance and cost effectiveness. However, the utilization of such smaller Pt NCs is always limited by the synthesis strategies, stability and methanol tolerance of Pt. Herein, unprotected Pt NCs (~2.2 nm) dispersed on carbon nanotubes (CNTs) were prepared via a modified top-down approach using liquid Li as a solvent to break down the bulk Pt. Compared with the commercial Pt/C, the resultant Pt NCs/CNTs catalyst (Pt loading: 10 wt.%) exhibited more desirable ORR catalytic performance in 0.1 M HClO4. The specific activity (SA) and mass activity (MA) at 0.9 V for ORR over Pt NCs/CNTs were 2.5 and 3.2 times higher than those over the commercial Pt/C (Pt loading: 20 wt.%). Meanwhile, the Pt NCs/CNTs catalyst demonstrated more satisfactory stability and methanol tolerance. Compared with the obvious loss (~69%) of commercial Pt/C, only a slight current decrease (~10%) was observed for Pt NCs/CNTs after the chronoamperometric measurement for 2 × 104 s. Hence, the as-prepared Pt NCs/CNTs material displays great potential as a practical ORR catalyst.

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