Characteristics of a gold-doped electrode for application in high-performance lithium-sulfur battery

Bulk sulfur incorporating 3 wt% gold nano-powder is investigated as possible candidate to maximize the fraction of active material in the Li-S battery cathode.The material is prepared via simple mixing of gold with molten sulfur at 120℃,quenching at room temperature,and grinding.Our comprehensive study reports relevant electrochemical data,advanced X-ray computed tomography(CT)imaging of the positive and negative electrodes,and a thorough structural and morphological characterization of the S:Au 97:3 w/w composite.This cathode exhibits high rate capability within the range from C/10 to 1C,a maximum capacity above 1300 mAh gs^-1,and capacity retention between 85%and 91%after 100 cycles at 1C and C/3 rates.The novel formulation enables a sulfur fraction in the composite cathode film as high as 78 wt%,an active material loading of 5.7 mg cm^-2,and an electrolyte/sulfur(E/S)ratio of 5μL mg^-1,which lead to a maximum areal capacity of 5.4 mAh cm^-2.X-ray CT at the micro-and nanoscale reveals the microstructural features of the positive electrode that favor fast conversion kinetics in the battery.Quantitative analysis of sulfur distribution in the porous cathode displays that electrodeposition during the initial cycle may trigger an activation process in the cell leading to improved performance.Furthermore,the tomography study reveals the characteristics of the lithium anode and the cell separator upon a galvanostatic test prolonged over 300 cycles at a 2C rate.     

Engineered Green Fluorescence Proteins for Proteomics and Biomolecular Electronic Applications

The discovery of the photochromic characteristics of engineered green fluorescent proteins (GFPs) allows new proteomics and biomolecular electronic applications. In particular, photoreversibility among two distinct optical states can lead to the realization of a bio-optical high density storage memory. Here we review our recent work on an optically bistable GFP and we report the recent developments of self-assembly methods for spatial immobilization of proteins into well-definite 2D patterns.     

Thick Coating and Functionalization of Organic Surfaces via ATRP in Water

Atom‐transfer radical polymerization has been used for polymerizing water‐soluble monomers from solid polymeric particles, intended as a model for any polymeric functional surface. Depending on the polarity of substrate and solvent, homogeneous initiation throughout the particles or pure surface initiation could be obtained. In the last case, polymer layers were obtained with thicknesses up to several tens of microns, still active for block copolymerization.