Journal of Materials Chemistry Blog

Dye-Sensitised Solar Cells (DSSCs) are a promising alternative to silicon-based photovoltaics and recently efficiencies over 12 % have been reported. Most DSSCs use organic solvents as liquid electrolyte as these have been reported to give the highest efficiencies. In this hot paper, O’Regan and co-workers have re-examined water as a solvent for use in DSSCs. In this study the authors use 100 % water electrolytes with inorganic salts such as NaI. They use a range of electrolyte compositions, film characteristics and four different dyes to show efficiencies of up to 4 %.

Managing wetting behavior and collection efficiency in photoelectrochemical devices based on water electrolytes; improvement in efficiency of water/iodide dye sensitised cells to 4%
J. Mater.  Chem., 2012, 22, 23387.  DOI: 10.1039/c2jm35245a (free to read for a short time)

Follow the latest journal news on Twitter @JMaterChem or go to our Facebook page.

To keep up-to-date with all the latest research, sign-up to our RSS feed or Table of contents alert.

Layered double hydroxides (LDHs) are a family of layered materials with composition [M_1-x^z+M_x³⁺(OH)₂]^a+(X^n–)_a/n.mH₂O. LiAl-X LDHs are a class of LDHs that have been extensively investigated due to their many applications as absorbents or in photochemistry. They can be synthesised in two ways; direct intercalation by treatment of gibbsite, bayerite or nördstrandite and hydrothermal treatment of a hydrated alumina gel with LiOH.

In this hot paper, The O’Hare group at the University of Oxford describe the first topotactic synthesis of rod-like LDH particles through that simultaneous intercalation of Li⁺ cations and X^– anions (X = Cl^–, and Br^–). Nanorods of LiAl-X were synthesised by intercalation of LiX into a rod-like morphology of gibbsite. The authors find that LiAl-X-rod can undergo further anion exchange intercalation with cyclamate into LiAl-Cl-rod.

Topotactic synthesis of layered double hydroxide nanorods
J. Mater. Chem., 2012, 22, 23064.  DOI: 10.1039/c2jm34670b (free to read for a short time)

Follow the latest journal news on Twitter @JMaterChem or go to our Facebook page.

To keep up-to-date with all the latest research, sign-up to our RSS feed or Table of contents alert.

The bacteria Gluconacetobacter xylinus produces cellulose that is highly crystalline and has a high degree of polymerisation. The cellulose can be converted into rod-like nanocrystals which have very high modulus and strength. A variety of nanocomposites can be prepared by incorporating cellulose nanocrystals with polymers to give materials with excellent properties. Silver nanoparticles are well known to improve the anti-bacterial properties of polymer materials.

Scientists in India have prepared a hybrid nanocomposite from the combination of cellulose nanocrystals and silver nanoparticles as reinforcing fillers for the polymer PVA. Both the nanocrystals and the silver nanoparticles improved the mechanical properties of the PVA films. The nanocrystals increased the modulus and tensile strength of the films, while the nanoparticles decreased the brittleness of the films. These effects could be useful in making more biocompatible materials for applications such as in tissue engineering.

Augmented properties of PVA hybrid nanocomposites containing cellulose nanocrystals and silver nanoparticles
J. Mater. Chem., 2012, 22, 22433.  DOI: 10.1039/c2jm35235d (free to read for a short time)

Follow the latest journal news on Twitter @JMaterChem or go to our Facebook page.

To keep up-to-date with all the latest research, sign-up to our RSS feed or Table of contents alert.

Cholesteric liquid crystals (CLCs) show selective reflection due to their helical structures. They are formed by the introduction of chiral elements into liquid crystals molecules or by doping of nematic liquid crystals with chiral dopants. Photoresponsive chiral dopants are increasing being used to fabricate tuneable CLCs.

In this hot paper, Liu and colleagues use an imprinting method which used multiple UV-induced polymerisations. A helical polymer matrix was imprinted in the presence of a CLC. Desirable Bragg reflections were found, without any added liquid crystals or chiral compounds.

Fabrication and characterization of imprinted photonic crystalline polymer matrices via multiple UV polymerizations
J. Mater.  Chem., 2012, 22, 22446.  DOI: 10.1039/c2jm35151j (free to read for a short time)

Follow the latest journal news on Twitter @JMaterChem or go to our Facebook page.

To keep up-to-date with all the latest research, sign-up to our RSS feed or Table of contents alert.