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Nanomaterials
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Design and Synthesis of Nanostructured Materials for Catalytic Applications
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Design and Synthesis of Nanostructured Materials for Catalytic Applications

A special issue of Nanomaterials (ISSN 2079-4991). This special issue belongs to the section "Energy and Catalysis".

Deadline for manuscript submissions: closed (31 December 2021) | Viewed by 32503

Special Issue Editor

Prof. Dr. Kyungsu Na

E-Mail Website
Guest Editor
Chonnam National University, Gwangju, South Korea
Interests: nanoporous materials; zeolites; metal oxides; metal nanoparticles; metal-organic framework; C1 chemistry; CO2 conversion; H2 production; heterogeneous catalysis
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Nanostructured materials have been attracting a great deal of attention in chemical industries due to their fascinating features, which originate from the nano effect. The development of nanotechnology in recent decades has enabled the design and systematic synthesis of various nanostructured materials, which have afforded new opportunities in many applications, including catalysis, electronics, optics, mechanics, the environment, energies, automobiles, and even healthcare. Nanostructured materials outperform their classical bulk-structured competitors by virtue of their unique chemical, physical, electrical, and mechanical characteristics, and their outstanding tunability. The catalytic opportunities for nanostructured materials are the focus of this Special Issue, which aims to cover the design of various nanostructured materials, such as metal nanoparticles, nanoporous crystals (i.e., metal oxides, zeolites, and metal–organic frameworks), and nanoporous carbons, for application in heterogeneous catalysis to control chemical reactions. We welcome the submission of communications, original research papers, and reviews on the following, or related, topics:

  • developments in the design and synthesis of nanostructured catalytic materials;
  • control of the size, shape, and components of metal nanoparticles for catalytic applications;
  • synthesis of crystalline nanoporous materials;
  • nanostructured materials for heterogeneous catalysis, including thermochemical, electrochemical, and photochemical reactions; and
  • theoretical studies on the design of nanostructured materials and prediction of their abilities.

Prof. Dr. Kyungsu Na
Guest Editor

Manuscript Submission Information

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Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Nanomaterials is an international peer-reviewed open access semimonthly journal published by MDPI.

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Keywords

  • metal nanoparticles
  • nanoporous metal oxides
  • zeolites
  • metal–organic frameworks
  • nanoporous carbons
  • heterogeneous catalysts.

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Published Papers (11 papers)

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Editorial

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3 pages, 181 KiB  
Editorial
Designed Synthesis of Nanostructured Materials as the Heterogeneous Catalysts
by Kyungsu Na
Nanomaterials 2022, 12(24), 4374; https://doi.org/10.3390/nano12244374 - 8 Dec 2022
Viewed by 1067
Abstract
The development of nanoscale syntheses and innovative characterization tools resulted in the tailored design of nanostructured materials with versatile abilities in many applications [...] Full article
(This article belongs to the Special Issue Design and Synthesis of Nanostructured Materials for Catalytic Applications)

Research

Jump to: Editorial

24 pages, 11093 KiB  
Article
Effect of Multiply Twinned Ag(0) Nanoparticles on Photocatalytic Properties of TiO2 Nanosheets and TiO2 Nanostructured Thin Films
by Snejana Bakardjieva, Jakub Mares, Eva Koci, Jakub Tolasz, Radek Fajgar, Vasyl Ryukhtin, Mariana Klementova, Štefan Michna, Hana Bibova, Randi Holmestad, Rositsa Titorenkova and Maria Caplovicova
Nanomaterials 2022, 12(5), 750; https://doi.org/10.3390/nano12050750 - 23 Feb 2022
Cited by 5 | Viewed by 3007
Abstract
Ag-decorated TiO2 nanostructured materials are promising photocatalysts. We used non-standard cryo-lyophilization and ArF laser ablation methods to produce TiO2 nanosheets and TiO2 nanostructured thin films decorated with Ag nanoparticles. Both methods have a common advantage in that they provide a [...] Read more.
Ag-decorated TiO2 nanostructured materials are promising photocatalysts. We used non-standard cryo-lyophilization and ArF laser ablation methods to produce TiO2 nanosheets and TiO2 nanostructured thin films decorated with Ag nanoparticles. Both methods have a common advantage in that they provide a single multiply twinned Ag(0) characterized by {111} twin boundaries. Advanced microscopy techniques and electron diffraction patterns revealed the formation of multiply twinned Ag(0) structures at elevated temperatures (500 °C and 800 °C). The photocatalytic activity was demonstrated by the efficient degradation of 4-chlorophenol and Total Organic Carbon removal using Ag-TiO2 nanosheets, because the multiply twinned Ag(0) served as an immobilized photocatalytically active center. Ag-TiO2 nanostructured thin films decorated with multiply twinned Ag(0) achieved improved photoelectrochemical water splitting due to the additional induction of a plasmonic effect. The photocatalytic properties of TiO2 nanosheets and TiO2 nanostructured thin films were correlated with the presence of defect-twinned structures formed from Ag(0) nanoparticles with a narrow size distribution, tuned to between 10 and 20 nm. This work opens up new possibilities for understanding the defects generated in Ag-TiO2 nanostructured materials and paves the way for connecting their morphology with their photocatalytic activity. Full article
(This article belongs to the Special Issue Design and Synthesis of Nanostructured Materials for Catalytic Applications)
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20 pages, 2159 KiB  
Article
New Solvent-Free Melting-Assisted Preparation of Energetic Compound of Nickel with Imidazole for Combustion Synthesis of Ni-Based Materials
by Oksana V. Komova, Svetlana A. Mukha, Anna M. Ozerova, Olga A. Bulavchenko, Alena A. Pochtar, Arcady V. Ishchenko, Galina V. Odegova, Alexey P. Suknev and Olga V. Netskina
Nanomaterials 2021, 11(12), 3332; https://doi.org/10.3390/nano11123332 - 8 Dec 2021
Cited by 5 | Viewed by 2611
Abstract
In this work two approaches to the synthesis of energetic complex compound Ni(Im)6(NO3)2 from imidazole and nicklel (II) nitrate were applied: a traditional synthesis from solution and a solvent-free melting-assisted method. According to infrared spectroscopy, X-ray diffraction, elemental [...] Read more.
In this work two approaches to the synthesis of energetic complex compound Ni(Im)6(NO3)2 from imidazole and nicklel (II) nitrate were applied: a traditional synthesis from solution and a solvent-free melting-assisted method. According to infrared spectroscopy, X-ray diffraction, elemental and thermal analysis data, it was shown that the solvent-free melt synthesis is a faster, simpler and environmentally friendly method of Ni(Im)6(NO3)2 preparation. The results show that this compound is a promising precursor for the production of nanocrystalline Ni-NiO materials by air-assisted combustion method. The combustion of this complex together with inorganic supports makes it possible to synthesize supported nickel catalysts for different catalytic processes. Full article
(This article belongs to the Special Issue Design and Synthesis of Nanostructured Materials for Catalytic Applications)
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14 pages, 6949 KiB  
Article
Controlled Metal–Support Interactions in Au/CeO2–Mg(OH)2 Catalysts Activating the Direct Oxidative Esterification of Methacrolein with Methanol to Methyl Methacrylate
by Nagyeong Kim, Seulgi Lim, Seungdon Kwon, Yuyeol Choi, Ji-Woong Lee and Kyungsu Na
Nanomaterials 2021, 11(11), 3146; https://doi.org/10.3390/nano11113146 - 21 Nov 2021
Cited by 3 | Viewed by 2461
Abstract
The strong metal–support interaction (SMSI) between the three components in Au/CeO2–Mg(OH)2 can be controlled by the relative composition of CeO2 and Mg(OH)2 and by the calcination temperature for the direct oxidative esterification of methacrolein (MACR) with methanol to [...] Read more.
The strong metal–support interaction (SMSI) between the three components in Au/CeO2–Mg(OH)2 can be controlled by the relative composition of CeO2 and Mg(OH)2 and by the calcination temperature for the direct oxidative esterification of methacrolein (MACR) with methanol to methyl methacrylate (MMA). The composition ratio of CeO2 and Mg(OH)2 in the catalyst affects the catalytic performance dramatically. An Au/CeO2 catalyst without Mg(OH)2 esterified MACR to a hemiacetal species without MMA production, which confirmed that Mg(OH)2 is a prerequisite for successful oxidative esterification. When Au/Mg(OH)2 was used without CeO2, the direct oxidative esterification of MACR was successful and produced MMA, the desired product. However, the MMA selectivity was much lower (72.5%) than that with Au/CeO2–Mg(OH)2 catalysts, which have an MMA selectivity of 93.9–99.8%, depending on the relative composition of CeO2 and Mg(OH)2. In addition, depending on the calcination temperature, the crystallinity of the CeO2–Mg(OH)2 and the surface acidity/basicity can be remarkably changed. Consequently, the Au-nanoparticle-supported catalysts exhibited different MACR conversions and MMA selectivities. The catalytic behavior can be explained by the different metal–support interactions between the three components depending on the composition ratio of CeO2 and Mg(OH)2 and the calcination temperature. These differences were evidenced by X-ray diffraction, X-ray photoelectron spectroscopy, and CO2 temperature-programmed desorption. The present study provides new insights into the design of SMSI-induced supported metal catalysts for the development of multifunctional heterogeneous catalysts. Full article
(This article belongs to the Special Issue Design and Synthesis of Nanostructured Materials for Catalytic Applications)
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14 pages, 4864 KiB  
Article
Comparing Internal and Interparticle Space Effects of Metal–Organic Frameworks on Polysulfide Migration in Lithium–Sulfur Batteries
by UnJin Ryu, Won Ho Choi, Panpan Dong, Jeeyoung Shin, Min-Kyu Song and Kyung Min Choi
Nanomaterials 2021, 11(10), 2689; https://doi.org/10.3390/nano11102689 - 12 Oct 2021
Cited by 2 | Viewed by 2787
Abstract
One of the critical issues hindering the commercialization of lithium–sulfur (Li–S) batteries is the dissolution and migration of soluble polysulfides in electrolyte, which is called the ‘shuttle effect’. To address this issue, previous studies have focused on separators featuring specific chemical affinities or [...] Read more.
One of the critical issues hindering the commercialization of lithium–sulfur (Li–S) batteries is the dissolution and migration of soluble polysulfides in electrolyte, which is called the ‘shuttle effect’. To address this issue, previous studies have focused on separators featuring specific chemical affinities or physical confinement by porous coating materials. However, there have been no studies on the complex effects of the simultaneous presence of the internal and interparticle spaces of porous materials in Li–S batteries. In this report, the stable Zr-based metal–organic frameworks (MOFs), UiO-66, have been used as a separator coating material to provide interparticle space via size-controlled MOF particles and thermodynamic internal space via amine functionality. The abundant interparticle space promoted mass transport, resulting in enhanced cycling performance. However, when amine functionalized UiO-66 was employed as the separator coating material, the initial specific capacity and capacity retention of Li–S batteries were superior to those materials based on the interparticle effect. Therefore, it is concluded that the thermodynamic interaction inside internal space is more important for preventing polysulfide migration than spatial condensation of the interparticle space. Full article
(This article belongs to the Special Issue Design and Synthesis of Nanostructured Materials for Catalytic Applications)
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13 pages, 2587 KiB  
Article
A Multifunctional Au/CeO2-Mg(OH)2 Catalyst for One-Pot Aerobic Oxidative Esterification of Aldehydes with Alcohols to Alkyl Esters
by Seulgi Lim, Seungdon Kwon, Nagyeong Kim and Kyungsu Na
Nanomaterials 2021, 11(6), 1536; https://doi.org/10.3390/nano11061536 - 10 Jun 2021
Cited by 11 | Viewed by 3121
Abstract
Au nanoparticles bound to crystalline CeO2 nanograins that were dispersed on the nanoplate-like Mg(OH)2, denoted as Au/CeO2-Mg(OH)2, were developed as the highly active and selective multifunctional heterogeneous catalyst for direct oxidative esterification of aldehydes with alcohols [...] Read more.
Au nanoparticles bound to crystalline CeO2 nanograins that were dispersed on the nanoplate-like Mg(OH)2, denoted as Au/CeO2-Mg(OH)2, were developed as the highly active and selective multifunctional heterogeneous catalyst for direct oxidative esterification of aldehydes with alcohols to produce alkyl esters under base-free aerobic conditions using oxygen or air as the green oxidants. Au/CeO2-Mg(OH)2 converted 93.3% of methacrylaldehyde (MACR) to methyl methacrylate (MMA, monomer of poly(methyl methacrylate)) with 98.2% selectivity within 1 h, and was repeatedly used over eight recycle runs without regeneration. The catalyst was extensively applied to other aldehydes and alcohols to produce desirable alkyl esters. Comprehensive characterization analyses revealed that the strong metal–support interaction (SMSI) among the three catalytic components (Au, CeO2, and Mg(OH)2), and the proximity and strong contact between Au/CeO2 and the Mg(OH)2 surface were prominent factors that accelerated the reaction toward a desirable oxidative esterification pathway. During the reaction, MACR was adsorbed on the surface of CeO2-Mg(OH)2, upon which methanol was simultaneously activated for esterifying the adsorbed MACR. Hemiacetal-form intermediate species were subsequently produced and oxidized to MMA on the surface of the electron-rich Au nanoparticles bound to partially reduced CeO2−x with electron-donating properties. The present study provides new insights into the design of SMSI-induced supported-metal-nanoparticles for the development of novel, multifunctional, and heterogeneous catalysts. Full article
(This article belongs to the Special Issue Design and Synthesis of Nanostructured Materials for Catalytic Applications)
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15 pages, 3558 KiB  
Article
Pore Modification and Phosphorus Doping Effect on Phosphoric Acid-Activated Fe-N-C for Alkaline Oxygen Reduction Reaction
by Jong Gyeong Kim, Sunghoon Han and Chanho Pak
Nanomaterials 2021, 11(6), 1519; https://doi.org/10.3390/nano11061519 - 8 Jun 2021
Cited by 4 | Viewed by 2675
Abstract
The price and scarcity of platinum has driven up the demand for non-precious metal catalysts such as Fe-N-C. In this study, the effects of phosphoric acid (PA) activation and phosphorus doping were investigated using Fe-N-C catalysts prepared using SBA-15 as a sacrificial template. [...] Read more.
The price and scarcity of platinum has driven up the demand for non-precious metal catalysts such as Fe-N-C. In this study, the effects of phosphoric acid (PA) activation and phosphorus doping were investigated using Fe-N-C catalysts prepared using SBA-15 as a sacrificial template. The physical and structural changes caused by the addition of PA were analyzed by nitrogen adsorption/desorption and X-ray diffraction. Analysis of the electronic states of Fe, N, and P were conducted by X-ray photoelectron spectroscopy. The amount and size of micropores varied depending on the PA content, with changes in pore structure observed using 0.066 g of PA. The electronic states of Fe and N did not change significantly after treatment with PA, and P was mainly found in states bonded to oxygen or carbon. When 0.135 g of PA was introduced per 1 g of silica, a catalytic activity which was increased slightly by 10 mV at −3 mA/cm2 was observed. A change in Fe-N-C stability was also observed through the introduction of PA. Full article
(This article belongs to the Special Issue Design and Synthesis of Nanostructured Materials for Catalytic Applications)
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14 pages, 2264 KiB  
Article
Biobased Carbon Dots: From Fish Scales to Photocatalysis
by Carlotta Campalani, Elti Cattaruzza, Sandro Zorzi, Alberto Vomiero, Shujie You, Lauren Matthews, Marie Capron, Claudia Mondelli, Maurizio Selva and Alvise Perosa
Nanomaterials 2021, 11(2), 524; https://doi.org/10.3390/nano11020524 - 18 Feb 2021
Cited by 29 | Viewed by 4647
Abstract
The synthesis, characterization and photoreduction ability of a new class of carbon dots made from fish scales is here described. Fish scales are a waste material that contains mainly chitin, one of the most abundant natural biopolymers, and collagen. These components make the [...] Read more.
The synthesis, characterization and photoreduction ability of a new class of carbon dots made from fish scales is here described. Fish scales are a waste material that contains mainly chitin, one of the most abundant natural biopolymers, and collagen. These components make the scales rich, not only in carbon, hydrogen and oxygen, but also in nitrogen. These self-nitrogen-doped carbonaceous nanostructured photocatalyst were synthesized from fish scales by a hydrothermal method in the absence of any other reagents. The morphology, structure and optical properties of these materials were investigated. Their photocatalytic activity was compared with the one of conventional nitrogen-doped carbon dots made from citric acid and diethylenetriamine in the photoreduction reaction of methyl viologen. Full article
(This article belongs to the Special Issue Design and Synthesis of Nanostructured Materials for Catalytic Applications)
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12 pages, 7162 KiB  
Article
Ruling Factors in Cinnamaldehyde Hydrogenation: Activity and Selectivity of Pt-Mo Catalysts
by Marta Stucchi, Maela Manzoli, Filippo Bossola, Alberto Villa and Laura Prati
Nanomaterials 2021, 11(2), 362; https://doi.org/10.3390/nano11020362 - 1 Feb 2021
Cited by 8 | Viewed by 3016
Abstract
To obtain selective hydrogenation catalysts with low noble metal content, two carbon-supported Mo-Pt bimetallic catalysts have been synthesized from two different molybdenum precursors, i.e., Na2MoO4 and (NH4)6Mo7O24. The results obtained by X-ray [...] Read more.
To obtain selective hydrogenation catalysts with low noble metal content, two carbon-supported Mo-Pt bimetallic catalysts have been synthesized from two different molybdenum precursors, i.e., Na2MoO4 and (NH4)6Mo7O24. The results obtained by X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) combined with the presence and strength of acid sites clarified the different catalytic behavior toward cinnamaldehyde hydrogenation. After impregnating the carbon support with Mo precursors, each sample was used either as is or treated at 400 °C in N2 flow, as support for Pt nanoparticles (NPs). The heating treatment before Pt deposition had a positive effect on the catalytic performance. Indeed, TEM analyses showed very homogeneously dispersed Pt NPs only when they were deposited on the heat-treated Mo/C supports, and XPS analyses revealed an increase in both the exposure and reduction of Pt, which was probably tuned by different MoO3/MoO2 ratios. Moreover, the different acid properties of the catalysts resulted in different selectivity. Full article
(This article belongs to the Special Issue Design and Synthesis of Nanostructured Materials for Catalytic Applications)
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24 pages, 12276 KiB  
Article
Surface Properties of 1DTiO2 Microrods Modified with Copper (Cu) and Nanocavities
by Snejana Bakardjieva, Filip Mamon, Zdenek Pinc, Radek Fajgar, Ivo Jakubec, Natalija Murafa, Eva Koci, Tatjana Brovdyova, Adriana Lancok, Stefan Michna and Rositsa Nikolova
Nanomaterials 2021, 11(2), 324; https://doi.org/10.3390/nano11020324 - 27 Jan 2021
Cited by 1 | Viewed by 2029
Abstract
This work deals with Cu-modified 1DTiO2 microrods (MRs) and their surface properties. The pristine lyophilized precursor Cu_1DTiO2, prepared by an environmentally friendly cryo-lyophilization method, was further annealed in the temperature interval from 500 to 950 °C. The microstructure of all [...] Read more.
This work deals with Cu-modified 1DTiO2 microrods (MRs) and their surface properties. The pristine lyophilized precursor Cu_1DTiO2, prepared by an environmentally friendly cryo-lyophilization method, was further annealed in the temperature interval from 500 to 950 °C. The microstructure of all samples was characterized by electron microscopy (SEM/EDS and HRTEM/SAED), X-ray powder diffraction (XRD), infrared spectroscopy, simultaneous DTA/TGA thermoanalytical measurement, and mass spectroscopy (MS). Special attention was paid to the surface structure and porosity. The 1D morphology of all annealed samples was preserved, but their surface roughness varied due to anatase-rutile phase transformation and the change of the nanocrystals habits due to nanocavities formation after releasing of confined ice-water. The introduction of 2 wt.% Cu as electronically active second species significantly reduced the direct bandgap of 1DTiO2 in comparison with undoped TiO2 and the standard Degussa TiO2_P25. All samples were tested for their UV absorption properties and H2 generation by PEC water splitting. We presented a detailed study on the surface characteristics of Cu doped 1DTiO2 MRs due to gain a better idea of their photocatalytic activity. Full article
(This article belongs to the Special Issue Design and Synthesis of Nanostructured Materials for Catalytic Applications)
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12 pages, 3587 KiB  
Article
Highly Efficient Mesoporous Core-Shell Structured Ag@SiO2 Nanosphere as an Environmentally Friendly Catalyst for Hydrogenation of Nitrobenzene
by Bonan Zhao, Zhipeng Dong, Qiyan Wang, Yisong Xu, Nanxia Zhang, Weixing Liu, Fangning Lou and Yue Wang
Nanomaterials 2020, 10(5), 883; https://doi.org/10.3390/nano10050883 - 3 May 2020
Cited by 15 | Viewed by 3607
Abstract
The size-uniformed mesoporous Ag@SiO2 nanospheres’ catalysts were prepared in one-pot step via reducing AgNO3 by different types of aldehyde, which could control the size of Ag@SiO2 NPs and exhibit excellent catalytic activity for the hydrogenation of nitrobenzene. The results showed [...] Read more.
The size-uniformed mesoporous Ag@SiO2 nanospheres’ catalysts were prepared in one-pot step via reducing AgNO3 by different types of aldehyde, which could control the size of Ag@SiO2 NPs and exhibit excellent catalytic activity for the hydrogenation of nitrobenzene. The results showed that the Ag core size, monitored by different aldehydes with different reducing abilities, together with the ideal monodisperse core-shell mesoporous structure, was quite important to affect its superior catalytic performances. Moreover, the stability of Ag fixed in the core during reaction for 6 h under 2.0 MPa, 140 °C made this type of Ag@SiO2 catalyst separable and environmentally friendly compared with those conventional homogeneous catalysts and metal NPs catalysts. The best catalyst with smaller Ag cores was prepared by strong reducing agents such as CH2O. The conversion of nitrobenzene can reach 99.9%, the selectivity was 100% and the catalyst maintained its activity after several cycles, and thus, it is a useful novel candidate for the production of aniline. Full article
(This article belongs to the Special Issue Design and Synthesis of Nanostructured Materials for Catalytic Applications)
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