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In recent years, recycling of numerous spent lithium-ion battery cathode materials has received increasing attention in order to protect the environment as well as to conserve resources, and the recovery of spent LiFePO4 (LFP) by direct regeneration has been widely studied. A considerable body of literature has delved into the failure mechanism of LFP. The mechanism is characterized by an irreversible phase change, which is primarily attributed to the sluggish diffusion of lithium ions (Li+) during cycling. Additionally, the migration of iron (Fe) ions to occupy Li+ sites further impedes Li+ diffusion. Consequently, the electrochemical performance of directly regenerated LFP is diminished by the phenomenon of Li defects. Here, a method of direct regeneration of LFP based on a doping strategy using environmentally friendly and economically efficient natural biomass amino acids has been developed, which inhibits Fe ion migration and improves the diffusion kinetics of Li+ and electrons by constructing a nitrogen-doped carbon coating. The regenerated LFP cathode exhibits excellent cycling stability and rate performance (98.7% capacity retention over 100 cycles at 1C current density and a high capacity retention of 87.9% after 500 cycles at 1C). [ABSTRACT FROM AUTHOR]

Simple low rate pre-activation effectively prolonged the cycle life of Li–O2 batteries with MWNT cathodes in a 1 M LiClO4/DMSO electrolyte from 55 to 290 cycles, and the ultimate capacity and rate performance were also significantly enhanced, attributed to reconstructed homogeneous and compact SEI layers on the Li anodes by pre-activation. [ABSTRACT FROM AUTHOR]

In this paper, gold nanorods and InP/ZnS quantum dots were encapsulated together in a silica medium, and the targeting molecular peptide c(RGDfC) was further connected after surface modification with PEG and PEG derivatives to prepare a multifunctional Au@QD@SiO2/PEG-c(RGDfC) probe. Dynamic Light Scattering showed that the probe size was about 215.01 ± 2.72 nm, and its dispersibility was good. In in vitro experiments when the concentration was as high as 200 μg mL−1, the activity of the cells was still 85% due to low toxicity. In vivo experiments showed that the probe had excellent tumor targeting, X-ray computed tomography (CT) imaging and fluorescence imaging capabilities. The experiments revealed that the probe had a long blood circulation time (T1/2 = 7.78 h) in mice. Biochemical analysis, liver enzyme analysis and histomorphological analysis after probe injection showed that the probe had no obvious side effects on the normal functions of the main organs, indicating good biosafety. In vivo imaging experiments showed that 6 d after intravenous injection, the tumor sites of a HeLa tumor-bearing nude mice positive group presented obvious fluorescence and CT signals, indicating that the prepared nanoprobe had good tumor targeting dual-mode imaging capabilities and therefore showed great potential in biomedical imaging applications, especially the diagnosis of cancer. [ABSTRACT FROM AUTHOR]

Simple low rate pre-activation effectively prolonged the cycle life of Li-O2 batteries with MWNT cathodes in a 1 M LiClO4/DMSO electrolyte from 55 to 290 cycles, and the ultimate capacity and rate performance were also significantly enhanced, attributed to reconstructed homogeneous and compact SEI layers on the Li anodes by pre-activation.

I, Yuan-Cheng Cao, hereby wholly retract this Analyst paper for correction. This article was submitted for publication without the knowledge and approval of the co-authors listed. Signed: Yuan-Cheng Cao, Newcastle University, UK, December 2011. This retraction is endorsed by May Copsey, Editor. Retraction published 16th December 2011.

Luminescent samarium (Sm) and europium (Eu) doped silica nanoparticles (SiO(2) NPs) were investigated for use in multiple target immunoassays. Particles with a diameter of 40 +/- 10 nm were synthesized and applied to multiplexed immunoassays in a single well of an assay plate. The luminescent behavior of the lanthanide doped NPs was compared to conventional dyes in solution and in surface confined model immunoassays against two analytes. Luminescence from the dyes and NPs was detected with an imaging spectroscopic system and this could be processed with a simple least squares procedure. In solution, NPs exhibited linear mixing behaviour while conventional fluorescent dyes required careful control to solution conditions, particularly pH. A conventional dye system consisting of FITC and Cy3 applied to a two analyte model system resulted in up to 70% energy transfer from FITC to Cy3 under conditions of high surface coverage. This made quantitative analysis intractable for unknown samples. The lanthanide doped silica nanoparticles responded well to both analytes (<5% relative std. dev.). The results demonstrate that NPs provide alternatives to conventional dyes due to low susceptibility to pH and related solution conditions, absence of energy transfer, single excitation wavelength range, and high stokes shift. These properties allowed quantitative analysis of multiple analytes in the same well.