Gels as Templates for Transcription

A special issue of Gels (ISSN 2310-2861).

Deadline for manuscript submissions: closed (30 June 2017) | Viewed by 23247

Special Issue Editor


E-Mail Website
Guest Editor
Departamento de Química Orgánica, UMYMFOR (CONICET-FCEN), Universidad de Buenos Aires, Piso 3, pabellón 2, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina
Interests: development and study of new physical gels; organogels as template for the preparation of nanoparticles; supramolecular chemistry; structure-gelating property relationship; steroid-derived physical gels; development of functional soft materials
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

The preparation of nanostructured materials with well-defined morphology and properties is of major importance due to their potential high-tech applications, and has become an interdisciplinary field that involves chemistry, solids and soft matter physics, biology, and materials science. The template technique, following the bottom-up approach, is one of the most important methods for the controlled synthesis of defined nanostructured materials in which the nano-object is chemically assembled from smaller elementary components (building blocks). In this area gels, with well-defined nano-dimensional superstructures, have become a versatile soft-material that can be used to guide the transcription of these structures to create inorganic and/or hybrid nanomaterials with a wide variety of morphologies such as nanotubes, helical tubes and ribbons, plates, etc.

This Special Issue focuses on the application of chemical and physical gels as molecular templates for the preparation of mesoporous, nanostructured inorganic, organic and/or hybrid materials and the study of the transcription process.

Prof. Dr. Pablo H. Di Chenna
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

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. Gels is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • template
  • transcription
  • nanotubes
  • nanoparticle
  • bottom-up
  • inorganic materials
  • hybrid materials
  • supramolecular templates
  • gel

Published Papers (5 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Editorial

Jump to: Research, Review

2 pages, 159 KiB  
Editorial
Gels as Templates for the Syntheses of Shape-Controlled Nanostructured Materials
by Pablo H. Di Chenna
Gels 2018, 4(1), 10; https://doi.org/10.3390/gels4010010 - 16 Jan 2018
Cited by 2 | Viewed by 2299
Abstract
The preparation of inorganic, organic and/or hybrid nanostructured materials with controlled shape and size is crucial for the development of nanotechnology, and it is nowadays the focus of intense research.[...] Full article
(This article belongs to the Special Issue Gels as Templates for Transcription)

Research

Jump to: Editorial, Review

12511 KiB  
Article
Metal Oxide/TiO2 Hybrid Nanotubes Fabricated through the Organogel Route
by Masahiro Suzuki, Keita Tanaka, Yukie Kato and Kenji Hanabusa
Gels 2017, 3(3), 24; https://doi.org/10.3390/gels3030024 - 22 Jun 2017
Cited by 6 | Viewed by 4542
Abstract
Titanium dioxide (TiO2) nanotube and its hybrid nanotubes (with various metal oxides such as Ta2O5, Nb2O5, ZrO2, and SiO2) were fabricated by the sol-gel polymerization in the ethanol gels formed [...] Read more.
Titanium dioxide (TiO2) nanotube and its hybrid nanotubes (with various metal oxides such as Ta2O5, Nb2O5, ZrO2, and SiO2) were fabricated by the sol-gel polymerization in the ethanol gels formed by simple l-lysine-based organogelator. The self-assembled nanofibers (gel fibers) formed by the gelator functioned as a template. The different calcination temperatures gave TiO2 nanotubes with various crystalline structures; e.g., anatase TiO2 nanotube was obtained by calcination at 600 °C, and rutile TiO2 nanotube was fabricated at a calcination temperature of 750 °C. In the metal oxide/TiO2 hybrid nanotubes, the metal oxide species were uniformly dispersed in the TiO2 nanotube, and the percent content of metal oxide species was found to correspond closely to the feed ratio of the raw materials. This result indicated that the composition ratio of hybrid nanotubes was controllable by the feed ratio of the raw materials. It was found that the metal oxide species inhibited the crystalline phase transition of TiO2 from anatase to rutile. Furthermore, the success of the hybridization of other metal oxides (except for TiO2) indicated the usefulness of the organogel route as one of the fabrication methods of metal oxide nanotubes. Full article
(This article belongs to the Special Issue Gels as Templates for Transcription)
Show Figures

Graphical abstract

16029 KiB  
Article
Transcription of Nanofibrous Cerium Phosphate Using a pH-Sensitive Lipodipeptide Hydrogel Template
by Mario Llusar, Beatriu Escuder, Juan De Dios López-Castro, Susana Trasobares and Guillermo Monrós
Gels 2017, 3(2), 23; https://doi.org/10.3390/gels3020023 - 10 Jun 2017
Cited by 8 | Viewed by 5566
Abstract
A novel and simple transcription strategy has been designed for the template-synthesis of CePO4·xH2O nanofibers having an improved nanofibrous morphology using a pH-sensitive nanofibrous hydrogel (glycine-alanine lipodipeptide) as structure-directing scaffold. The phosphorylated hydrogel was employed as a template to [...] Read more.
A novel and simple transcription strategy has been designed for the template-synthesis of CePO4·xH2O nanofibers having an improved nanofibrous morphology using a pH-sensitive nanofibrous hydrogel (glycine-alanine lipodipeptide) as structure-directing scaffold. The phosphorylated hydrogel was employed as a template to direct the mineralization of high aspect ratio nanofibrous cerium phosphate, which in-situ formed by diffusion of aqueous CeCl3 and subsequent drying (60 °C) and annealing treatments (250, 600 and 900 °C). Dried xerogels and annealed CePO4 powders were characterized by conventional thermal and thermogravimetric analysis (DTA/TG), and Wide-Angle X-ray powder diffraction (WAXD) and X-ray powder diffraction (XRD) techniques. A molecular packing model for the formation of the fibrous xerogel template was proposed, in accordance with results from Fourier-Transformed Infrarred (FTIR) and WAXD measurements. The morphology, crystalline structure and composition of CePO4 nanofibers were characterized by electron microscopy techniques (Field-Emission Scanning Electron Microscopy (FE-SEM), Transmission Electron Microscopy/High-Resolution Transmission Electron Microscopy (TEM/HRTEM), and Scanning Transmission Electron Microscopy working in High Angle Annular Dark-Field (STEM-HAADF)) with associated X-ray energy-dispersive detector (EDS) and Scanning Transmission Electron Microscopy-Electron Energy Loss (STEM-EELS) spectroscopies. Noteworthy, this templating approach successfully led to the formation of CePO4·H2O nanofibrous bundles of rather co-aligned and elongated nanofibers (10–20 nm thick and up to ca. 1 μm long). The formed nanofibers consisted of hexagonal (P6222) CePO4 nanocrystals (at 60 and 250 °C), with a better-grown and more homogeneous fibrous morphology with respect to a reference CePO4 prepared under similar (non-templated) conditions, and transformed into nanofibrous monoclinic monazite (P21/n) around 600 °C. The nanofibrous morphology was highly preserved after annealing at 900 °C under N2, although collapsed under air conditions. The nanofibrous CePO4 (as-prepared hexagonal and 900 °C-annealed monoclinic) exhibited an enhanced UV photo-luminescent emission with respect to non-fibrous homologues. Full article
(This article belongs to the Special Issue Gels as Templates for Transcription)
Show Figures

Graphical abstract

6229 KiB  
Article
Synthesis of Helical Phenolic Resin Bundles through a Sol-Gel Transcription Method
by Changzhen Shao, Jiangang Li, Hao Chen, Baozong Li, Yi Li and Yonggang Yang
Gels 2017, 3(1), 9; https://doi.org/10.3390/gels3010009 - 23 Feb 2017
Cited by 6 | Viewed by 5016
Abstract
Chiral and helical polymers possess special helical structures and optical property, and may find applications in chiral catalysis and optical devices. This work presents the preparation and formation process of helical phenolic resins through a sol-gel transcription method. A pair of bola-type chiral [...] Read more.
Chiral and helical polymers possess special helical structures and optical property, and may find applications in chiral catalysis and optical devices. This work presents the preparation and formation process of helical phenolic resins through a sol-gel transcription method. A pair of bola-type chiral low-molecular-weight gelators (LMWGs) derived from valine are used as templates, while 2,4-dihydroxybenzoic acid and formaldehyde are used as precursors. The electron microscopy images show that the phenolic resins are single-handed helical bundles comprised of helical ultrafine nanofibers. The diffused reflection circular dichroism spectra indicate that the helical phenolic resins exhibit optical activity. A possible formation mechanism is proposed, which shows the co-assembly of the LMWGs and the precursors. Full article
(This article belongs to the Special Issue Gels as Templates for Transcription)
Show Figures

Graphical abstract

Review

Jump to: Editorial, Research

3342 KiB  
Review
Single-Handed Helical Polybissilsesquioxane Nanotubes and Mesoporous Nanofibers Prepared by an External Templating Approach Using Low-Molecular-Weight Gelators
by Jing Hu and Yonggang Yang
Gels 2017, 3(1), 2; https://doi.org/10.3390/gels3010002 - 1 Jan 2017
Cited by 10 | Viewed by 4491
Abstract
Chiral low-molecular-weight gelators (LMWGs) derived from amino acids can self-assemble into helical fibers and twisted/coiled nanoribbons by H-bonding and π–π interaction. Silica nanotubes with single-handed helices have been prepared using chiral LMWGs through sol–gel transcription. Molecular-scale chirality exists at the inner surfaces. Here, [...] Read more.
Chiral low-molecular-weight gelators (LMWGs) derived from amino acids can self-assemble into helical fibers and twisted/coiled nanoribbons by H-bonding and π–π interaction. Silica nanotubes with single-handed helices have been prepared using chiral LMWGs through sol–gel transcription. Molecular-scale chirality exists at the inner surfaces. Here, we discuss single-handed helical aromatic ring-bridged polybissilsesquioxane nanotubes and mesoporous nanofibers prepared using chiral LMWGs. This review aims at describing the formation mechanisms of the helical nanostructures, the origination of optical activity, and the applications for other helical nanomaterial preparation, mainly based on our group’s results. The morphology and handedness can be controlled by changing the chirality and kinds of LMWGs and tuning the reaction conditions. The aromatic rings arrange in a partially crystalline structure. The optical activity of the polybissilsesquioxane nanotubes and mesoporous nanofibers originates from chiral defects, including stacking and twisting of aromatic groups, on the inner surfaces. They can be used as the starting materials for preparation of silica, silicon, carbonaceous, silica/carbon, and silicon carbide nanotubes. Full article
(This article belongs to the Special Issue Gels as Templates for Transcription)
Show Figures

Graphical abstract

Back to TopTop