Journal of Materials Chemistry Blog

Three new hydroxy double salt (HDS) nanocomposites containing medicinal and agrochemical anions were prepared Dermot O’Hare and co-workers and their potential as sustained release matrices demonstrated in this Hot Article from the team based at Oxford University.

HDSs consist of layers of comprise positively charged layers, requiring charge balancing anions to be located between the layers to ensure electroneutrality. These anions can be easily replaced through an anion exchange process.  HDS have received far less attention than the related Layered double hydroxides (LDHs) which have been widely explored as hosts for the storage and controlled release of a broad spectrum of functional anions.

In this study two drug anions were chosen for investigation (ibuprofen and diclofenac, commonly used non-steroidal anti-inflammatory drugs) and an examplar agrochemical 2,4,5-trichlorophenoxyacetic acid, a widely used herbicide. The functional anion intercalates were thoroughly characterised, and the release of the functional anion studied in vitro in representative conditions. Mathematical models were applied to the release kinetics, and post-synthesis modification undertaken to optimise release times for industrial application.

Interested in knowing more?  Read for free until January 4th 2011

Hydroxy double salts as versatile storage and delivery matrices
Richard M. R. Bull, Charles Markland, Gareth R. Williams and Dermot O’Hare
J. Mater. Chem., 2011, Advance Article
DOI: 10.1039/C0JM03020A, Paper

In order to broaden the application fields of poly (vinylidene fluoride) (PVDF), a promising approach is introducing nanofillers into the polymer. In this paper from Wei-Hong Zhong and co-workers a facile method for surface modification of nanofillers has been developed in order to improve interfacial interaction and dispersion within PVDF matrix.

Rather than using the more conventional toxic fluorine gas method of treating nanofillers, the team from Beihang University and Washington State University developed a new method of depositing a fluorination coating from decomposition of polytetrafluoroethylene (PTFE) on a carbon nanofiber (CNF) surface. This study confirms that the new surface coating method provides a simpler way for practical modification of nanofillers, i.e. through decompositions of polymers.

Interested in knowing more? Read for free until January 4th 2011.

Fluorination deposition on carbon nanofibers by PTFE decomposition as a facile method to enhance dispersion and interaction in PVDF composites
Li-Li Sun, Zuo-Guang Zhang and Wei-Hong Zhong
J. Mater. Chem., 2011, Advance Article
DOI: 10.1039/C0JM03260C, Paper

The design of new materials for gaseous NOx (NO and NO2) removal at ambient temperature using organic active sites is reported in this paper from a team from the University of California at Berkeley. The materials consist of unfunctionalised silica and silica modified by immobilized aminoxyls and function via cascade reactions consisting of NO oxidation to NO2 and NO2 adsorption.The application of cascade reactions is an emerging research area that spans synthetic and biological catalysts, and has the potential to integrate the unique properties of both types of catalysts within a single process.

Interested in knowing more?  Read for free until January 4^th 2011.

Silica-supported aminoxyls as reactive materials for NO_x removal 
Tatiana Luts, Enrique Iglesia and Alexander Katz
J. Mater. Chem., 2011, Advance Article
DOI: 10.1039/C0JM02826F, Paper

In this Feature Article, Hongtao Liu, Yunqi Liu and Daoben Zhu present a summary of chemical doping of graphene aimed at tuning the electronic properties.  The authors, from the Chinese Academy of Sciences, focus on p-type and n-type doping of graphene and band gap tuning in graphene.

Recently, a lot of effort has been focused on improving the performance and exploring the electric properties of graphene with the aim of designing high performance electronic devices based on chemically doped graphene.

Interested in knowing more? Read for free until 4th January 2011

Chemical doping of graphene
Hongtao Liu, Yunqi Liu and Daoben Zhu
J. Mater. Chem., 2011, Advance Article
DOI: 10.1039/C0JM02922J, Feature Article

This highlight article by Petra Cameron and co-workers at the University of Bath and the University of Liverpool describes recent activity in the area of peptide self-assembly, with a particular focus on tri-peptides, dipeptides and protected amino acids.

Low molecular weight gelators (LMWGs) are small molecules that self-assemble under the right conditions to form fibrous nanostructures, which can further associate into higher order structures. Of particular interest are LMW peptide hydrogelators which are biomimetic and form translucent hydrogels when added to water.  The gels typically contain >99% water and have been suggested for applications in regenerative tissue engineering, 3-D cell culturing, bio-templating, drug delivery, enzyme immobilisation and biosensing.

Interested in knowing more?  Read for free until December 23^rd.

Peptide based low molecular weight gelators
Eleanor K. Johnson, Dave J. Adams and Petra J. Cameron
J. Mater. Chem., 2011, Advance Article
DOI: 10.1039/C0JM03099F, Highlight

A team from Zhejiang University have fabricated a novel luminescent sheet by deposition of cadmium selenide nanoparticles onto cellulose nanofibres of commercial filter paper.

Semi-conductor nanocrystals, particularly cadmium selenide (CdSe) quantum dots (QDs), have triggered intensive research interest because of their fascinating luminescent properties.  A key step in broadening the practical applications is to stabilize the nanocrystals into matrices to get bulk solid state materials.

Jianguo Huang and co-workers in China fabricated a hierarchical luminescent cellulose sheet via self-assembly of cadmium selenide (CdSe) nanoparticles capped with trioctylphosphine oxide (TOPO) and 1-hexadecylamine (HDA) onto ultrathin titania film pre-coated cellulose nanofibres of bulk natural cellulose substance (common commercial filter paper).

This approach provides a facile shortcut to fabricate bulk luminescent materials that inherit the mechanical behaviour of cellulose substances and simultaneously possess designed luminescent properties.

Interested in knowing more? Read for free until December 21^st.

Luminescent cellulose sheet fabricated by facile self-assembly of cadmium selenide nanoparticles on cellulose nanofibres
Tao Niu, Yuanqing Gu and Jianguo Huang
J. Mater. Chem., 2011, Advance Article
DOI: 10.1039/C0JM02356F, Paper