Covalent molecular assembly in supercritical carbon dioxide: Formation of nanoparticles in immobilized dendrimers within a porous silica gel matrix

Puniredd, Sreenivasa Reddy; Nguan, Bellamy Chia Choon; Srinivasan, M.P.

doi:10.1016/j.jcis.2008.10.084

Cited by 10 publications

(5 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Fourier Transform Infrared Spectroscopy (FTIR) Analysis. In addition to XPS on a silicon surface, FTIR spectra analysis was carried out on both piranha-treated silica 51 and β-CD-grafted silica in SCCO 2 to confirm the successful immobilization of β-CD on the silica surface (Supporting Information Figure 2S.) The appearance of the peaks at 2910 and 1390 cm −1 were attributed to asymmetric stretch (−CH 2 −) methyl peaks and bending vibrations of C−OH groups of the immobilized β-CD.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

Universal Single-Step Approach to the Immobilization of Cyclodextrins in a Supercritical Medium for Capturing Drug, Dye, and Metal Nanoclusters

Bhartia

Das

Jayaraman³

et al. 2023

Langmuir

Self Cite

View full text Add to dashboard Cite

By utilizing nanoreactor-like structures, the immobilization of macromolecules such as calixarenes and cyclodextrins (CD) with bucket-like structures provides new possibilities for engineered surface-molecule systems. The practical use of any molecular system depends on the availability of a universal procedure for immobilizing molecules with torus-like structures on various surfaces while maintaining identical operating parameters. There are currently several steps, including toxic solvent-based approaches using modified β-CD to covalently attach to surfaces with multistep reactions. However, the existing multistep process results in molecular orientation, restricts the accessibility of the hydrophobic barrel of β-CD’s for practical use, and is effectively unable to use the surfaces immobilized with β-CD for a variety of applications. In this study, it was demonstrated that β-CD attached to the oxide-based semiconductor and metal surfaces through a condensation reaction between the hydroxyl-terminated oxide-based semiconductor/metal oxide and β-CD in supercritical carbon dioxide (SCCO2) as a medium. The primary benefit of SCCO2-assisted grafting of unmodified β-CD on various oxide-based metal and semiconductor surfaces is that it is a simple, efficient, one-step process and that it is ligand-free, scalable, substrate-independent, and uses minimal energy. Various physical microscopy and chemical spectroscopic methods were used to analyze the grafted β-CD oligomers. The application of the grafted β-CD films was demonstrated by the immobilization of rhodamine B (RhB), a dye, and dopamine, a drug. The in situ nucleation and growth of silver nanoclusters (AgNCs) in the molecular systems were studied for antibacterial and tribological properties by utilizing the guest–host interaction ability of β-CD.

show abstract

Section: ■ Results and Discussionmentioning

confidence: 99%

Universal Single-Step Approach to the Immobilization of Cyclodextrins in a Supercritical Medium for Capturing Drug, Dye, and Metal Nanoclusters

Bhartia

Das

Jayaraman³

et al. 2023

Langmuir

Self Cite

View full text Add to dashboard Cite

show abstract

“…In another publication, the formation of Pd, Pt and Pd/Pt nanoparticles in dendrimerladen assemblies immobilized within a silica gel matrix and constructed by covalent layer-by-layer assembly using supercritical carbon dioxide was investigated. 109 Furthermore, the highly efficient nitridosilicate phosphors were synthesized at low temperatures using a novel precursor route involving metal amides. 110 Finally, another publication focused on the production of copper particles and films by forming Cu(II) compound films on substrates using a displacement from two immiscible supercritical phases technique followed by reducing the copper(II) compound films in hydrogen at 200 °C.…”

Section: Resultsmentioning

confidence: 99%

“…Considering the recent publications, in one of them supercritical fluid reactive deposition was used for the deposition of highly dispersed platinum nanoparticles with controllable metal content and particle size distribution on beta-cyclodextrin, and the cellular uptake of these platinum nanoparticles in human colon carcinoma cells was investigated which is a good example of particle formation and activity determination study and therefore complementing each other. In another publication, the formation of Pd, Pt and Pd/Pt nanoparticles in dendrimer-laden assemblies immobilized within a silica gel matrix and constructed by covalent layer-by-layer assembly using supercritical carbon dioxide was investigated . Furthermore, the highly efficient nitridosilicate phosphors were synthesized at low temperatures using a novel precursor route involving metal amides .…”

Section: Resultsmentioning

confidence: 99%

The Breadth and Intensity of Supercritical Particle Formation Research with an Emphasis on Publication and Patent Disclosures

Yeşil-Çeliktaş

Senyay

2010

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

The drawbacks of the conventional mechanical treatments for particle micronization often resulting in product damage or performance degradation have highlighted the need for alternative particle formation processes. The aim of this study was to shed light on the trends of the scientific studies and innovations in the field of particle formation using supercritical fluids (SCF) in order to observe the progress of science and technology and to satisfy the need for a global view of research activities. The publications in the ISI Web and the patents in a patent database were screened using nine different keywords in title or topics. A total of 939 journal publication and 206 patent disclosures between 1980-2009, with the contributions of 3588 authors and 604 innovators, were found to focus on particle formation using SCF. The results showed that the majority of the publication (59.2%) and patent (40.3%) disclosures were related to antisolvent precipitation and rapid expansion of SCF (18.3,16%). Patents originating from United States (56.8%) were dominating, followed by those from the European Union (30.1%) and Japan (9.2%). The analysis revealed the appetite of the companies for commercialization (73.8%), which can be interpreted as an indicator of upcoming industrial applications.

show abstract

“…21,26 Addition of small amounts of entrainers such as alcohols to scCO 2 can result in an increase in the solubility of metal precursors in scCO 2 . Alcohols [27][28][29][30] and organic solvents [31][32][33][34][35][36] have been used to attain higher solubilities of metal precursors in scCO 2 .…”

Section: Supercritical Depositionmentioning

confidence: 99%

Review—Supercritical Deposition: A Powerful Technique for Synthesis of Functional Materials for Electrochemical Energy Conversion and Storage

Barim

Uzunlar

Bozbağ

et al. 2020

J. Electrochem. Soc.

View full text Add to dashboard Cite

Supercritical fluid-based technologies are increasingly being used to develop novel functional nanostructured materials or improve the properties of existing ones. Among these, supercritical deposition (SCD) is an emerging technique to incorporate metals on supports. It has been used to deposit a wide variety of single or multi-metallic morphologies such as highly dispersed species, nanoparticles, nanorods and conformal films on high surface area supports, polymers and crystalline substrates. SCD is also attracting increasing attention for preparation of micro or nano-architectured functional materials in a highly controllable manner for electrochemical energy conversion and storage systems. Increasing number of studies in the literature demonstrates that materials synthesized using SCD are comparable or superior in performance as compared to their conventional counterparts. In this review, an overview of the fundamentals of the SCD technique is presented. Properties of a wide variety of nanostructured functional materials such as supported nanoparticles and films prepared using SCD for electrochemical applications are summarized. The electrochemical performance of these materials in electrochemical tests and also in fuel cells, electrolyzers and Li-ion batteries are also presented.

show abstract

Covalent molecular assembly in supercritical carbon dioxide: Formation of nanoparticles in immobilized dendrimers within a porous silica gel matrix

Cited by 10 publications

References 26 publications

Universal Single-Step Approach to the Immobilization of Cyclodextrins in a Supercritical Medium for Capturing Drug, Dye, and Metal Nanoclusters

Universal Single-Step Approach to the Immobilization of Cyclodextrins in a Supercritical Medium for Capturing Drug, Dye, and Metal Nanoclusters

The Breadth and Intensity of Supercritical Particle Formation Research with an Emphasis on Publication and Patent Disclosures

Review—Supercritical Deposition: A Powerful Technique for Synthesis of Functional Materials for Electrochemical Energy Conversion and Storage

Contact Info

Product

Resources

About