News

Ada Della Pia and Giovanni Costantini publish the Scanning Tunnelling Microscopy chapter for the Springer Surface Science Techniques book, Gianangelo Bracco and Bodil Holst (ed).

The Gibson Group publishes in Biomaterials Science on why certain (macro)molecules are capable of inhibiting ice crystal growth, inspired by antifeeze proteins.

The work, conducted in collaboration with Warwick Medical School provides insights into which structural features are essential for a (macro)molecule to inhibit ice crystal growth and why apparently similar compounds have opposing activity.

The ability to control ice crystal growth is a major technological challenge (anyone stuck at Heathrow or scraping their car...?) with many biotechnological applications.

Read the paper here

The Jones group in collaboration with UCL, Imperial College and the LCN investigate the effect of fluorination on the magnetic properties of phthalocyanine thin films in the Journal of Applied Physics.

In a recent issue of Angewandte Chemie the Warwick team of Emanuele Maggio, Natalia Martsinovich and Alessandro Troisi reports a new design strategy to improve dye sentitized solar cells. Good dyes, when excited by solar radiation, inject very rapidly an electron to the semiconductor they are adsorbed onto. However it is also desirable that, when they have lost the electron, these dyes are not neutralized again by the semiconductor. The authors combined ideas from group theory with their methodology to study electron transfer at the interface to propose a new family of dyes that inject the electron rapidly but are very reluctant to take the electron back.

Soft materials which can be molded into specific shapes and contain emulsion droplets or bubbles are an important class of materials and find use accross a wide range of disciplines. Think for example of shaving foam, margerine spreads, etc. An important class of soft materials are so-called hydrogels, which can be made from watersoluble polymer molecules and form a gel through crosslinking a phenonomenon that interconnects the polymer chains creating a network.

Stefan Bon and his team (BonLab) now has shown that hydrogel objects which contain large amounts of oil droplets (80 vol%) can be constructed through injection (molding) of an emulsified mixture of oil and a waterborne dispersion of thermoresponsive poly(N-isopropyl acrylamide) nanogel particles, which are crosslinked through non-covalent interaction of 2-ureido-4[1H] pyrimidinone (UPy) groups.

Stefan Bon says "we are very excited that we can trap isolated oil droplets into hydrogels macroscopic objects, which can be re-shaped. For example, it is possible to make a cylindrical high internal phase emulsion hydrogel wire. The reversibility of the hydrogen bond formation means that these materials will have exciting physical and mechanical characteristics. Not only that, the use of the thermoresponsive poly(N-isopropyl acrylamide) allows us to shrink and thus squeeze the objects at elevated temperatures, which has potential interesting applications in triggered delivery of active ingredients and microscopic engines and motors."

Their findings are published in Chemical Communications (link to the paper), a journal by the Royal Society of Chemistry.

The Tim Jones group have collaborated with the Chris McConville group in physics to publish work in the Journal of Physical Chemistry C, exploring the optimisation of a solution processed vanadium oxide hole-extracting layer for organic photovoltaic (OPV) cells.

Daniel Phillips, a 2nd year PhD student in the Gibson Group, won the prize for best poster at the RSC Postgraduate Nanoscience Symposium held at the University of Birmingham.

Read some of Dan's publications in Chem Commun and Biomacromolecules

The Lewandowski group in collaboration with scientists from IBS Grenoble, ENS Lyon and University of Illinois Urbana-Champaign report in the Journal of Physical Chemistry Letters one of the first comparisons of 200 ns MD simulation of a protein in a crystalline form with dynamic parameters obtained from solid-state NMR measurements. This study tests the accuracy of commonly applied procedures for the interpretation of experimental solid-state relaxation data in terms of dynamic modes and time scales.

Read the full article

The Hatton group report in ACS Applied Materials and Interfaces the fabrication, exceptional properties, and application of 8 nm thick Cu, Ag, Au, and Cu/Ag bilayer electrodes on flexible polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) substrates. These electrodes have a sheet resistance of ≤14 Ω sq^–1, are exceptionally robust and can be rapidly thermally annealed at 200 °C to reduce their sheet resistance to ≤9 Ω sq^–1. The power conversion efficiency of 1 cm² organic photovoltaics (OPVs) employing 8 nm Ag and Au films as the hole-extracting window electrode exhibit performance comparable to those on indium–tin oxide, with the advantage that they are resistant to repeated bending through a small radius of curvature and are chemically well-defined. OPVs employing Cu and bilayer Cu:Ag electrodes exhibit inferior performance due to a lower open-circuit voltage and fill factor. Measurements of the interfacial energetics made using the Kelvin probe technique provide insight into the physical reason for this difference. The results show how coinage metal electrodes offer a viable alternative to ITO on flexible substrates for OPVs and highlight the challenges associated with the use of Cu as an electrode material in this context.

The Gibson group with collaborators at ETH Zurich report in Advanced Functional Materials on how synthetic polymers tethered to the surface of an enzyme can produce a 'molecular sieving' effect. Polymer-Protein conjugates are widely studied for their pharmaceutical applications, but the phase behaviour of the polymers has not be probed in detail previously. These results open the door to 'smart' PEGylation of proteins with selective permeability properties.

Read the full paper here

The Hatton group report in Advanced Materials a low cost window electrode for organic photovoltaics which simultaneously removes the requirement for conducting oxide and conventional low work function electrodes and functions as a sink for oxygen/water in the heart of the device. Remarkably the functionality of this electrode, which is based on a 7.8 nm nanostructured Cu:Al film, improves upon in-situ oxidation as demonstrated in bulk heterojunction organic photovoltaics.

http://onlinelibrary.wiley.com/doi/10.1002/adma.201203280/abstract

The Hatton group report in Advanced Energy Materials a lithography-free method for the fabrication of optically-thin plasmon-active metal window electrodes with a dense array of nano-sized apertures on glass and plastic substrates. These remarkably robust, low sheet resistance electrodes simultaneously concentrate light and extract charge carriers in both polymer and vacuum deposited organic photovoltaics, and outperform indium-tin oxide electrodes on flexible substrates.

http://onlinelibrary.wiley.com/doi/10.1002/aenm.201200502/abstract