Showing papers by "Richard W. Siegel published in 2012"
TL;DR: A new class of both p- and n-type bulk nanomaterials with room-temperature ZT as high as 1.1 is demonstrated using a combination of sub-atomic-per-cent doping and nanostructuring to address the challenge of obtaining thermoelectric materials with high figure of merit ZT in thin films.
Abstract: In the quest for more efficient thermoelectrics, a common strategy has been to introduce nanostructures in bulk crystals, thus reducing the thermal conductivity without affecting the electrical transport properties. A route is now presented in which the aggregation of nanoplatelets creates nanostructured materials that have higher thermoelectric efficiencies than their bulk counterparts.
479 citations
TL;DR: A better understanding and control over nanoparticle surface chemistry has allowed researchers to begin to understand how spatial arrangement of atomic and molecular species at an interface can affect protein adsorption, structure, and subsequent biological outcomes.
Abstract: The promise of nanobiomaterials for diagnostic and therapeutic biomedical applications has been widely reported throughout the scientific community, and great strides have been made in those directions. And yet, the translation of nanomaterial-based therapeutics to clinical applications remains an elusive target. Many challenges have blocked the usage of nanomaterials in biomedicine, including potential toxicity, immunogenicity, and decreased efficacy. In order to overcome some of these issues, detailed studies have been undertaken to understand fundamental interactions between nanomaterials and the biological environment. In particular, recent developments in nanoparticle synthesis, a better understanding and control over nanoparticle surface chemistry, as well as the organization of that chemistry on the nanoparticle surface, has allowed researchers to begin to understand how spatial arrangement of atomic and molecular species at an interface can affect protein adsorption, structure, and subsequent biol...
97 citations
TL;DR: Nanoparticles, as well as the final form of the resulting protein conjugates, were thoroughly characterized through various physical, microscopic, and spectroscopic techniques, and additional insight into the influence of nanoscale surface properties was obtained, which will enhance fundamental understanding of how such properties affect protein structure and function.
60 citations
TL;DR: It is suggested that nanoparticle size and protein structure influence protein orientation on SNPs, and 4 nm SNPs induce greater structural stabilization than 15 nm particles, presumably due to greater surface curvature of the former.
Abstract: We describe a method for determining the orientation of cytochrome c, RNase A, and lysozyme on silica nanoparticles (SNPs) using chemical modification combined with proteolysis-mass spectrometry. The proteins interacted with SNPs through preferential adsorption sites, which are dependent on SNP diameter; 4 nm SNPs induce greater structural stabilization than 15 nm particles, presumably due to greater surface curvature of the former. These results suggest that nanoparticle size and protein structure influence protein orientation on SNPs.
58 citations
TL;DR: These unique composite systems exhibit several favorable characteristics, namely, fine-tuned control over coating nanoporosity and thickness, excellent adhesion between the nanoporous coating and polymer substrate, and the ability to withstand significant and repeated bending.
Abstract: Nanoporous coatings have become the subject of intense investigation, in part because they have been shown to have unique and tailorable physical properties that can depart greatly from their dense or macroscopic counterparts. Nanoporous coatings are frequently fabricated utilizing oblique-angle or glancing-angle physical vapor-phase deposition techniques. However, a significant limitation for such coatings exists; they are almost always deposited on smooth and rigid planar substrates, such as silicon and glass. This limitation greatly constrains the applicability, tailorability, functionality and even the economic viability, of such nanoporous coatings. Here, we report our findings on nanoporous/polymer composite systems (NPCS) fabricated by utilizing oblique-angle electron-beam methodology. These unique composite systems exhibit several favorable characteristics, namely, (i) fine-tuned control over coating nanoporosity and thickness, (ii) excellent adhesion between the nanoporous coating and polymer sub...
7 citations