Thermal annealing activates amplified photoluminescence of germanium metabolically doped in diatom biosilica: Germanium doped in diatom (a single celled algae) biosilica creates highly photoluminescent frustules which are uniquely patterned on the nano- and micro-scale. Using diatoms to make photoluminescent Ge doped silica instead of industrial production methods has several advantages. The structures are made biologically avoiding the extremes of temperature, pressure, power and the need for sophisticated equipment. The team behind the research say that biologically fabricated photoluminescent nanostructured silicon and germanium metal oxide materials have comparable optoelectronic and chemical properties to industrially fabricated Si–Ge metal oxide materials. (J. Mater. Chem., 2011, DOI:10.1039/C1JM10861A, Advance Article)
Archive for 2011
Hot Article: Creating photoluminescent doped silica with biology
Hot Articles on thermo-responsive nanovalves, NaGdF4:Eu3+ nanorods, and magnetic hollow nanotubes
Vapor-based synthesis of ultrathin hydrogel coatings for thermo-responsive nanovalves: Thermo-responsive nanovalves were fabricated by depositing ultrathin hydrogel coatings inside nanoporous track-etched polycarbonate membranes. The hydrogel coatings swell in response to changes in temperature, controlling the flow through a channel and creating a nanovalve. (J. Mater. Chem., 2011, DOI: 10.1039/C1JM10713E, Advance Article)
Efficient quantum cutting in hexagonal NaGdF4:Eu3+ nanorods: single phase, oxygen free, hexagonal NaGdF4:Eu3+ (2 mol%) nanorods with a visible quantum efficiency of 187% were prepared using an ionic liquid assisted solvothermal method. The team behind this research was led by Anja-Verena Mudring from Ruhr-Universität Bochum, Germany. (J. Mater. Chem., 2011, DOI:10.1039/C1JM10728C Advance Article)
Synthesis of magnetic hollow nanotubes based on the kirkendall effect for MR contrast agent and colorimetric hydrogen peroxide sensor: A simple solvothermal approach to synthesize hollow Mn ferrite nanostructures was developed by scientists in Taiwan. The team say that these high magnetic Mn ferrite nanotubes significantly enhance the magnetic resonance imaging contrast signal. (J. Mater. Chem., 2011, DOI:10.1039/C1JM10429B, Advance Article)
Read all the articles for free until 14th June
A trio of Hot Articles on engineering MOFs, the effect of nanoheterostructures and AuPt heterodimers
Engineering structured MOF at nano and macroscales for catalysis and separation: In this Hot Article, Sonia Aguado, Jerome Canivet and David Farrusseng from the Université Lyon 1, France, present for the first time the combination of the postfunctionalization of a MOF with its shaping as structured bodies. The team demonstrate that it is possible to achieve multiscale engineering of a MOF for catalytic and separation applications, which they claim could help create MOFs for use in industry. (J. Mater. Chem., 2011, DOI:10.1039/C1JM10787A, Advance Article)
Nanoheterostructures on TiO2 nanobelts achieved by acid hydrothermal method with enhanced photocatalytic and gas sensitive performance: Double heterostructure TiO2 nanobelts exhibit a much higher photocatalytic activity than normal TiO2 nanobelts and single heterostructure TiO2 nanobelts say scientists at Shandong University, China and Bowling Green State University, US. Optimising the nanobelt surface nanoheterostructure provides a broad approach to modify the physical properties and should have wide applications in photocatalysts, solar cells, chemical/bio sensors, and other techniques they claim. (J. Mater. Chem., 2011, DOI:10.1039/C1JM10588D, Advance Article)
Pt nanocrystal evolution in the presence of Au(III)-salts at room temperature: spontaneous formation of AuPt heterodimers: A straightforward synthesis of AuPt heterodimers performed at room temperature using oleylamine as the reducer and Pt seeds has been developed by Spanish scientists. The presence of Pt nanocrystals markedly accelerates the nucleation rate of Au, which suggest it acts as both nucleation platforms and initial catalytic reducers. (J. Mater. Chem., 2011, DOI:10.1039/C1JM10313J, Advance Article)
Read the articles for free until 10th June
Hot Articles on nanowire arrays for Schottky diodes, an anticancer bio-conjugate and a flower-like sensor
Fabrication and characterization of well-aligned, high density ZnO nanowire arrays and their realizations in Schottky device applications using a two-step approach: A two-step approach for preparing a large area array of high density and horizontally well-aligned of zinc oxide nanowires, has been developed by German and Chinese scientists. The team claim that these arrays are suitable for preparing Schottky diodes on inexpensive and flexible polymer substrates. (J. Mater. Chem., 2011, 21, 7090-7097)
TAT-conjugated nanodiamond for the enhanced delivery of doxorubicin: The anticancer drug doxorubicin and cell penetrating peptide TAT were conjugated to the surface of nanodiamonds. The conjugate is designed to avoid premature release and enhance the intracellular delivery of the drug. The team says that conjugation of TAT to nanodiamond–doxorubicin increases the cytotoxicity of doxorubicin compared to the free drug. (J. Mater. Chem., 2011, DOI: 10.1039/C1JM10653H, Advance Article)
Flower-like hydroxyapatite modified carbon paste electrodes applicable for highly sensitive detection of heavy metal ions: A team of scientists based in China and the UK have created a highly sensitive sensor for the detection of Pb2+ and Cd2+ ions. The sensor uses flower-like hydroxyapatite crystals fabricated on egg-shell membranes as modifiers for a chemically modified carbon paste electrode. (J. Mater. Chem., 2011, DOI: 10.1039/C1JM10949A, Advance Article)
Read this week’s Hot Articles from Journal of Materials Chemistry
Synthesis of magnetic hollow periodic mesoporous organosilica with enhanced cellulose tissue penetration behaviour: A team of scientists based in Australia have created nanoparticles designed to penetrate plant cell walls. The hybrid particles show excellent cellulose tissue penetrating performance, with relatively high magnetic response and high enzyme loading capacity. The team claim that the enhanced penetration of cellulose tissue could potentially be used for targeted delivery into plant cells. (J. Mater. Chem., 2011, DOI:10.1039/C1JM10615E, Advance Article)
The structural evolution and diffusion during the chemical transformation from cobalt to cobalt phosphide nanoparticles: Knowledge about the structural rearrangements occurring during the chemical transformation of nanoparticles could help tailor the synthesis and composition of the nanoparticles to improve their properties. In this Hot Article a team at Cornell University, USA, report the atomic and morphological structure of Cobalt nanoparticles as they are transformed into cobalt phosphide using X-ray absorption spectroscopy, XRD, TEM, and DFT calculations. (J. Mater. Chem., 2011, DOI:10.1039/C1JM10337G Advance Article)
Polymer-stabilized optically isotropic liquid crystals for next-generation display and photonics applications: In this Hot Feature Article Shin-Tson Wu and the team explain why polymer-stabilized optically isotropic liquid crystals, including blue phases, are emerging as a strong contender for next-generation display technology. (J. Mater. Chem., 2011, DOI:10.1039/C1JM10711A, Advance Article)
Interested to know more? Read all the articles for free until the 3rd June.
Journal of Materials Chemistry article on fabricating polymer/nanoparticle composite capsules highlighted by ACS Noteworthy Chemistry
Controllably layer-by-layer self-assembled polyelectrolytes/nanoparticle blend hollow capsules and their unique properties: Polymer/nanoparticle composite capsules with controllable incorporation of nanoparticles were fabricated by Layer-by-Layer blend self-assembly. The team from Singapore claim this offers a universal approach to fabricate well-dispersed microcapsules with controllable incorporation of nanoparticles for various applications such as intelligent drug delivery, biosensing, and bioimaging. (J. Mater. Chem., 2011, 21, 5148-5155.)
Journal of Materials Chemistry poster prize winner!
Congratulations to Mark Holden from the University of Manchester, UK, for winning the Journal of Materials Chemistry poster prize at the recent 34th Annual British Zeolite Association Conference. Mark’s winning poster was titled “In-situ Atomic Force Microscopy observation of the crystal growth of Sodalite Zincophosphate”.
Hot Articles on the redox behaviour in solid oxide fuels, the magnetic properties of Li-batteries and a film with photoswitchable conductivity.
High-temperature redox chemistry of La1.5+xSr0.5−xCo0.5Ni0.5O4+δ (x = 0.0, 0.2) studied in situ by neutron diffraction. A team from France and the UK has found first structural evidence of the coexistence of both anion vacancies and interstitial anions in a type of materials that could be used for solid oxide fuels. The team used neutron powder diffraction to study the redox behaviour of two n = 1 Ruddlesden–Popper oxides in real time as the sample was heated and exposed to H2. (J. Mater. Chem., 2011, DOI: 10.1039/C1JM10445D, Advance Article)
What can we learn about battery materials from their magnetic properties? In this Hot Article M. Stanley Whittingham and co-workers discuss how the connection between the magnetic properties and the electronic and atomic structure in Li-ion battery materials can been used to reveal details about the electrochemical performance of the battery materials. (J. Mater. Chem., 2011, DOI: 10.1039/C1JM00024A, Advance Article)
Switchable photoconductivity of quantum dot films using cross-linking ligands with light-sensitive structures. Using a light sensitive ligand to cross-link films of CdSe quantum dots can be used to create electrical junctions with photoswitchable conductivity say a team of US scientists. The team from Northwestern University led by Emily Weiss achieved an enhancement in the current density by an average factor of 6.5 times upon switching from visible excitation to UV excitation, which induces the ligand to switch from an open, non-conductive form to a closed, conductive form. (J. Mater. Chem., 2011, Advance Article DOI:10.1039/C0JM04397D)
Interested to know more? Read the full articles for free until 26th May
J. Mater. Chem. Article on graphene oxide–hydrogel networks highlighted by ACS Noteworthy Chemistry
A Journal of Materials Chemistry article has been highlighted by the ACS Noteworthy Chemistry website. The article “A one-step strategy for thermal- and pH-responsive graphene oxide interpenetrating polymer hydrogel networks” by Shengtong Sun and Peiyi Wu from Fudan University, China, describes a strategy for making interpenetrating PNIPAM hydrogel networks containing graphene oxide. The cross-linking reaction is highly efficient, resulting in a hydrogel network with better mechanical strength and a two-level structural hierarchy. The hydrogel is also pH-sensitive due to the existence of residual carboxyl groups. (Shengtong Sun and Peiyi Wu, J. Mater. Chem., 2011, 21, 4095-4097.)
Top Ten most-read Journal of Materials Chemistry articles in March
Read the most-read Journal of Materials Chemistry articles of March 2011, listed below:
DOI: 10.1039/B920539J
DOI: 10.1039/C0JM01163K
DOI: 10.1039/C0JM02631J
DOI: 10.1039/C0JM02922J
DOI: 10.1039/C0JM02991B
DOI: 10.1039/C0JM04225K
DOI: 10.1039/C0JM04412A
DOI: 10.1039/C0JM02319A
DOI: 10.1039/C0JM03287E
DOI: 10.1039/C0JM02699A