Christopher B. Murray

Bio: Christopher B. Murray is an academic researcher from University of Pennsylvania. The author has contributed to research in topics: Nanocrystal & Quantum dot. The author has an hindex of 88, co-authored 336 publications receiving 54410 citations. Previous affiliations of Christopher B. Murray include Universal Display Corporation & Lawrence Berkeley National Laboratory.

Methane Oxidation on Pd@ZrO2/Si–Al2O3 Is Enhanced by Surface Reduction of ZrO2

Abstract: The catalytic properties of Pd@ZrO2 core–shell catalysts supported on Si-modified alumina were studied for application to methane oxidation and compared to the analogous Pd@CeO2 catalysts. In the absence of water (dry conditions), both Pd@ZrO2 and Pd@CeO2 were highly active and showed nearly identical reaction rates and thermal stabilities. However, unlike catalysts based on Pd@CeO2, the Pd@ZrO2 catalysts were also very stable in the presence of high concentrations of water vapor. By means of Coulometric titration and pulse-reactor studies, we demonstrate that ZrO2 in contact with Pd can be reduced. Additionally, Coulometric titration showed that the Pd-PdO equilibrium at 600 °C is shifted to much lower P(O2) in the Pd@ZrO2 catalyst compared to conventional Pd/ZrO2 or Pd/Al2O3 catalysts. Because PdO is more active for methane oxidation, this observation provides a possible explanation for the superior performance of the Pd@ZrO2 catalyst.

Engineering charge injection and charge transport for high performance PbSe nanocrystal thin film devices and circuits

Abstract: We study charge injection and transport in PbSe nanocrystal thin films. By engineering the contact metallurgy and nanocrystal ligand exchange chemistry and surface passivation, we demonstrate partial Fermi-level pinning at the metal-nanocrystal interface and an insulator-to-metal transition with increased coupling and doping, allowing us to design high conductivity and mobility PbSe nanocrystal films. We construct complementary nanocrystal circuits from n-type and p-type transistors realized from a single nanocrystal material by selecting the contact metallurgy.

In vivo multiple color lymphatic imaging using upconverting nanocrystals

Abstract: Upconverting nanocrystals are unique nano-sized particles that emit light at shorter wavelengths (visible and near infrared) after excitation in the near infrared that dramatically reduces background autofluorescence in in vivo two color lymphatic imaging for depicting the lymphatic channels and nodes.

Engineering titania nanostructure to tune and improve its photocatalytic activity

Abstract: Photocatalytic pathways could prove crucial to the sustainable production of fuels and chemicals required for a carbon-neutral society. Electron−hole recombination is a critical problem that has, so far, limited the efficiency of the most promising photocatalytic materials. Here, we show the efficacy of anisotropy in improving charge separation and thereby boosting the activity of a titania (TiO2) photocatalytic system. Specifically, we show that H2 production in uniform, one-dimensional brookite titania nanorods is highly enhanced by engineering their length. By using complimentary characterization techniques to separately probe excited electrons and holes, we link the high observed reaction rates to the anisotropic structure, which favors efficient carrier utilization. Quantum yield values for hydrogen production from ethanol, glycerol, and glucose as high as 65%, 35%, and 6%, respectively, demonstrate the promise and generality of this approach for improving the photoactivity of semiconducting nanostructures for a wide range of reacting systems.

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

Semiconductor Clusters, Nanocrystals, and Quantum Dots

Abstract: Current research into semiconductor clusters is focused on the properties of quantum dots-fragments of semiconductor consisting of hundreds to many thousands of atoms-with the bulk bonding geometry and with surface states eliminated by enclosure in a material that has a larger band gap. Quantum dots exhibit strongly size-dependent optical and electrical properties. The ability to join the dots into complex assemblies creates many opportunities for scientific discovery.

Quantum Dot Bioconjugates for Ultrasensitive Nonisotopic Detection

Abstract: Highly luminescent semiconductor quantum dots (zinc sulfide-capped cadmium selenide) have been covalently coupled to biomolecules for use in ultrasensitive biological detection. In comparison with organic dyes such as rhodamine, this class of luminescent labels is 20 times as bright, 100 times as stable against photobleaching, and one-third as wide in spectral linewidth. These nanometer-sized conjugates are water-soluble and biocompatible. Quantum dots that were labeled with the protein transferrin underwent receptor-mediated endocytosis in cultured HeLa cells, and those dots that were labeled with immunomolecules recognized specific antibodies or antigens.