Showing Spotlights 441 - 448 of 2140 in category (newest first):
Heat energy can be converted into electricity with very high efficiency through a temperature-induced electron flow process known as thermionic emission. Thermionic energy converters have been used with different heat sources, all of them requiring operation at high temperatures above 1500 K. A new study indicates that heat temperature can be lowered by an order of magnitude if using graphene as hot cathode. The findings indicate that a graphene-based cathode thermionic converter operating at 900 K could reach an efficiency of 45%.
Mar 5th, 2015
Supercapacitors offer an alternative source of energy to replace rechargeable batteries for various applications, such as mobile electronics and electric vehicles. Among the various types of supercapacitors, carbon nanotube based devices have shown an order of magnitude higher performance in terms of energy and power densities. The bottleneck for transferring this technology to the marketplace, however, is the lack of efficient and scalable nanomanufacturing methods. Researchers have now developed a new scalable method to to directly spraycoat CNT-based supercapacitor electrodes.
Mar 3rd, 2015
Energy-scavenging fabrics based on nano-sized generators that have piezoelectric properties could eventually lead to wearable 'smart' clothes that can power integrated electronics and sensors through ordinary body movements. Researchers have now demonstrated a new type of fully flexible, very robust and wearable triboelectric nanogenerator with high power-generating performance and mechanical robustness. This was achieved by applying a bottom-up nanostructuring approach where a silver-coated textile and polydimethylsiloxane (PDMS) nanopatterns based on ZnO nanorod arrays were used as active triboelectric materials.
Feb 25th, 2015
Existing fabrication techniques for 3D microstructures usually suffer from complicated equipment, time-consuming processes, and insufficient controllability on precise structures. Constructing controllable 3D self-assembly microstructure in a simple and convenient way is still a challenge. In new work, researchers propose a facile strategy to directly assemble nanoparticles into controllable 3D structures from one microdroplet based on 0D hydrophilic pinning pattern.
Feb 24th, 2015
Meeting the need for a reliable, sensitive, and accurate methodology for the detection of nanoparticles in complex samples, using low-cost and portable instrumentation, scientists have developed a novel methodology to quickly screen for the presence and reactivity of nanoparticles in commercial, environmental, and biological samples. A colorimetric assay - similar to a swimming pool test kit - tests for the presence or absence of nanoparticles in biological and environmental relevant samples with sufficient sensitivity at part per billion concentration levels.
Feb 20th, 2015
Researchers report a non-destructive and high throughput 3D imaging of carbon nanotubes (CNTs) embedded in polymer matrix via Scanning Electron Microscopy (SEM). While have been several open questions remaining for SEM subsurface imaging of CNTs, this new findings clarify these issues and help establish SEM subsurface imaging as a useful and facile method to provide quantitative 3D information on CNT dispersions in polymer composites.
Feb 18th, 2015
An international team of researchers used abiotic assays, cultured cancer cells, and a melanoma animal model to demonstrate the photothermal therapy (PTT) activity of copper sulfide nanocrystals. The research lays out the working principle of colloidal, near-infrared light (NIR) plasmonic copper sulfide nanocrystals exploitable for both photodynamic therapy (PDT) and PTT therapy with NIR activation. This is the first report that under a NIR light radiation copper sulfide nanocrystals achieve efficient cancer destroying efficacy via PTT and PDT mechanisms both in vitro and in vivo.
Feb 17th, 2015
In an effort to find a way to introduce folds or waves into graphene in a simple and large-scale way, researchers have invented a rubber-stamp printing method to introduce waves into the graphene. The ability to controllably form folds in graphene has significant research and technological applications. Induced folds have a sublithographic width and macroscopic length. They could be used as channel materials or interconnects in chips, and it has been shown that stable field emitters are formed by folded graphene.
Feb 16th, 2015