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Gold nanoraspberries were synthesized by a seed-mediated synthesis with polyethylene glycol-functionalized bisphosphonates. The original structure shifted the optical absorption to infrared, revealing very efficient photothermal properties within the 2nd biological transparency window and leading to cancer cell necrosis at moderate intracellular doses and low (safe) laser power. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (NIBs) are emerging as a potentially cheaper alternative to lithium-ion batteries (LIBs) due to the larger abundance of sodium and in some cases the similar intercalation chemistry to LIBs. Here we report the solid state synthesized K-modified P2 Na0.7Mn0.8Mg0.2O2 which adopts hexagonal P63/mmc symmetry. The second charge/discharge capacity for the as-prepared material is 115/111 mA h g−1 between 1.5–4.2 V at a current density of 15 mA g−1, which reduces to 61/60 mA h g−1 after 100 cycles. Scanning transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy (STEM-EDS) analysis shows a heterogeneous distribution of K and solid state 23Na NMR illustrates that the presence of K perturbs the local environment of Na within the P2 Na0.7Mn0.8Mg0.2O2 crystal structure. Larger scale X-ray absorption near-edge structure (XANES) data on the K L-edge also illustrate that K is present on the surface of electrodes in preference to the bulk. In situ synchrotron X-ray diffraction (XRD) data illustrates that the P2 structural motif is preserved, featuring a solid solution reaction for most of charge–discharge except at the charged and discharged states where multiple phases are present. The K-modified sample of P2 Na0.7Mn0.8Mg0.2O2 is compared with the K-free samples in terms of both structural evolution and electrochemical performance. [ABSTRACT FROM AUTHOR]

Multiwall carbon nanotubes (MWCNTs) have been applied extensively in various aspects of advanced materials development. However, the purification of multi-walled carbon nanotubes and the removal of internally confined metal impurities, without compromising the CNT structural integrity, have proved to be a great challenge. The presence of inherent metal impurities has increased the complexity and health risks associated with the use of MWCNTs. In this study, we developed a low-cost purification strategy to effectively remove encapsulated metal impurities. MWCNTs synthesized by Ni-catalyzed chemical vapor deposition (CVD), were annealed in the presence of melamine under Ar-atmosphere protection at 1000 °C. Electron microscopy indicated that the pyrolysis of MWCNTs in the presence of melamine induces the leaching of encapsulated Ni particles via the tube open-end or the defect sites found along the MWCNTs. With this method, the leached impurities were shown to be more susceptible and accessible to acid purification. Upon acid treatment, ultrapure MWCNTs with trace amounts of metallic impurities (＜0.01 wt%) can be achieved. Alternatively, the leached metal nanoparticles could serve as highly efficient electrocatalytically active sites for oxygen evolution reactions with a turn over frequency (TOF) of 0.61 s−1. [ABSTRACT FROM AUTHOR]

Rice husks (or rice hulls) pre-treated with aqueous potassium hydroxide solutions showed excellent glucose yields during enzymatic saccharification. CO2 addition to the hydroxide solutions precipitated the dissolved rice husk silica as a nanoporous powder, while Ca(OH)2 addition regenerated the hydroxide solution and precipitated the dissolved lignin. Fractionation of the biomass was thus achieved using CO2 addition as a reversible pH-switch, and the hydroxide could be repeatedly recycled while maintaining biomass pre-treatment and fractionation efficacy. [ABSTRACT FROM AUTHOR]

Here, we report the effect of oleylamine (OLA) stabilizing molecules on the stability of iron–iron oxide core–shell nanoparticles in the electron beam. The presence of excess OLA (＞50 wt%) induces the structural transformation in the highly crystalline, core–shell structures to form hollow iron oxide nanoparticles after 120 s of electron beam exposure. [ABSTRACT FROM AUTHOR]

Herein we report the rational design of new phosphopeptides for control of nucleation, growth and aggregation of water-soluble, superparamagnetic iron–iron oxide core–shell nanoparticles. The use of the designed peptides enables a one-pot synthesis that avoids utilizing unstable or toxic iron precursors, organic solvents, and the need for exchange of capping agent after synthesis of the NPs. [ABSTRACT FROM AUTHOR]

Here we report a new, bench-top synthesis for iron/iron oxide core/shell nanoparticles viathe thermal decomposition of Fe(η5-C6H3Me4)2. The iron/iron oxide core/shell nanoparticles are superparamagnetic at room temperature and show improved negative contrast in T2-weighted MR imaging compared to pure iron oxides nanoparticles, and have a transverse relaxivity (r2) of 332 mM−1s−1. [ABSTRACT FROM AUTHOR]

The shape of nanoparticles is a key performance parameter for many applications, ranging from nanophotonics to nanomedicines. However, the unavoidable shape variations, which occur even in precision-controlled laboratory synthesis, can significantly impact on the interpretation and reproducibility of nanoparticle performance. Here we have developed an unsupervised, soft classification machine learning method to perform metrology of convex-shaped nanoparticles from transmission electron microscopy images. Unlike the existing methods, which are based on hard classification, soft classification provides significantly greater flexibility in being able to classify both distinct shapes, as well as non-distinct shapes where hard classification fails to provide meaningful results. We demonstrate the robustness of our method on a range of nanoparticle systems, from laboratory-scale to mass-produced synthesis. Our results establish that the method can provide quantitative, accurate, and meaningful metrology of nanoparticle ensembles, even for ensembles entailing a continuum of (possibly irregular) shapes. Such information is critical for achieving particle synthesis control, and, more importantly, for gaining deeper understanding of shape-dependent nanoscale phenomena. Lastly, we also present a method, which we coin the "binary DoG", which achieves significant progress on the challenging problem of identifying the shapes of aggregated nanoparticles., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Here we report a new, bench-top synthesis for iron/iron oxide core/shell nanoparticles via the thermal decomposition of Fe(η(5)-C(6)H(3)Me(4))(2). The iron/iron oxide core/shell nanoparticles are superparamagnetic at room temperature and show improved negative contrast in T(2)-weighted MR imaging compared to pure iron oxides nanoparticles, and have a transverse relaxivity (r(2)) of 332 mM(-1) s(-1).