Enhanced Electrochemical Performance of Ca-Doped NaV(PO)F/C Cathode Materials for Sodium-Ion Batteries.

NaV(PO)F (NVPF) with a NASICON structure has garnered attention as a cathode material owing to its stable 3D structure, rapid ion diffusion channels, high operating voltage, and impressive cycling stability. Nevertheless, the low intrinsic electronic conductivity of the material leading to a poor rate capability presents a significant challenge for practical application. Herein, we develop a series of Ca-doped NVPF/C cathode materials with various Ca doping levels using a simple sol-gel and carbon thermal reduction approach.

Tuning the Crystallinity and Coverage of SiO-ZnInS Core-Shell Nanoparticles for Efficient Hydrogen Generation.

The coverage, thickness, and crystallinity of ZnInS (ZIS) shells on SiO core nanoparticles (SiO@ZIS) were systematically investigated using microwave-assisted solvothermal methods aided by the addition of acid in ethanolic medium. The surface modification of the SiO cores with (3-mercaptopropyl)trimethoxysilane was found to be critical to generate a homogeneous coverage of ZnInS. The SiO@ZIS core-shell nanoparticles exhibited the best coverage but poor crystallinity when synthesized in pure ethanol, whereas best crystallinity but poor coverage was observed when synthesized in an aqueous solution.

Hollow Gold-Silver Nanoshells Coated with Ultrathin SiO Shells for Plasmon-Enhanced Photocatalytic Applications.

This article details the preparation of hollow gold-silver nanoshells (GS-NSs) coated with tunably thin silica shells for use in plasmon-enhanced photocatalytic applications. Hollow GS-NSs were synthesized via the galvanic replacement of silver nanoparticles. The localized surface plasmon resonance (LSPR) peaks of the GS-NSs were tuned over the range of visible light to near-infrared (NIR) wavelengths by adjusting the ratio of silver nanoparticles to gold salt solution to obtain three distinct types of GS-NSs with LSPR peaks centered near 500, 700, and 900 nm.

Optically Tunable Tin Oxide-Coated Hollow Gold-Silver Nanorattles for Use in Solar-Driven Applications.

Core@shell metal nanoparticles have emerged as promising photocatalysts because of their strong and tunable plasmonic properties; however, marked improvements in photocatalytic efficiency are needed if these materials are to be widely used in practical applications. Accordingly, the design of new and functional light-responsive nanostructures remains a central focus of nanomaterial research. To this end, we report the synthesis of nanorattles comprising hollow gold-silver nanoshells encapsulated within vacuous tin oxide shells of adjustable thicknesses (∼10 and ∼30 nm for the two examples prepared in this initial report).

Composition Modulation of Ionic Liquid Hybrid Electrolyte for 5 V Lithium-Ion Batteries.

Electrolyte is a key component in high-voltage lithium-ion batteries (LIBs). Bis(trifluoromethanesulfonyl)imide-based ionic liquid (IL)/organic carbonate hybrid electrolytes have been a research focus owing to their excellent balance of safety and ionic conductivity. Nevertheless, corrosion of Al current collectors at high potentials usually happens for this kind of electrolyte.

Temperature-Responsive Hydrogel-Coated Gold Nanoshells.

Gold nanoshells (~160 nm in diameter) were encapsulated within a shell of temperature-responsive poly(-isopropylacrylamide--acrylic acid) (P(NIPAM--AA)) using a surface-bound rationally-designed free radical initiator in water for the development of a photothermally-induced drug-delivery system. The morphologies of the resultant hydrogel-coated nanoshells were analyzed by scanning electron microscopy (SEM), while the temperature-responsive behavior of the nanoparticles was characterized by dynamic light scattering (DLS). The diameter of the P(NIPAM--AA) encapsulated nanoshells decreased as the solution temperature was increased, indicating a collapse of the hydrogel layer with increasing temperatures.

Broadening the photoresponsive activity of anatase titanium dioxide particles via decoration with partial gold shells.

Titanium dioxide (TiO) has gained increasing interest in materials research due to its outstanding properties and promising applications in a wide range of fields. From this perspective, we report the synthesis of custom-designed anatase TiO submicrometer particles coated with partial Au shells (ATiO-AuShl). The synthetic strategy used herein yields uniformly shaped monodisperse particles.

Electrolyte Engineering: Optimizing High-Rate Double-Layer Capacitances of Micropore- and Mesopore-Rich Activated Carbon.

Various types of electrolyte cations as well as binary cations are used to optimize the capacitive performance of activated carbon (AC) with different pore structures. The high-rate capability of micropore-rich AC, governed by the mobility of desolvated cations, can outperform that of mesopore-rich AC, which essentially depends on the electrolyte conductivity.

Eco-Efficient Synthesis of Highly Porous CoCO Anodes from Supercritical CO for Li and Na Storage.

An eco-efficient synthetic route for the preparation of high-performance carbonate anodes for Li and Na batteries is developed. With supercritical CO (scCO ) as the precursor, which has gas-like diffusivity, extremely low viscosity, and near-zero surface tension, CoCO particles are uniformly formed and tightly connected on graphene nanosheets (GNSs). This synthesis can be conducted at 50 °C, which is considerably lower than the temperature required for conventional preparation methods, minimizing energy consumption.

Silver-Free Gold Nanocages with Near-Infrared Extinctions.

This article reports the preparation of silver-free Au nanocages from cubic palladium templates. Pd nanocubes were subjected to galvanic replacement with Au to produce Pd@Au nanocages having tunable dimensions (i.e.

Plasmonically Enhanced Photocatalytic Hydrogen Production from Water: The Critical Role of Tunable Surface Plasmon Resonance from Gold-Silver Nanoshells.

Gold-silver nanoshells (GS-NSs) having a tunable surface plasmon resonance (SPR) were employed to facilitate charge separation of photoexcited carriers in the photocalytic production of hydrogen from water. Zinc indium sulfide (ZnIn2S4; ZIS), a visible-light-active photocatalyst, where the band gap varies with the [Zn]/[In] ratio, was used as a model ZIS system (E(g) = 2.25 eV) to investigate the mechanisms of plasmonic enhancement associated with the nanoshells.

MoS2/graphene cathodes for reversibly storing Mg(2+) and Mg(2+)/Li(+) in rechargeable magnesium-anode batteries.

Commercial micron-scale low-cost MoS2 is subjected to an electrochemically derived 2H-to-1T phase transformation, which makes it capable of reversibly storing Mg(2+)/Li(+) and Mg(2+) in all-phenyl-complex (APC) electrolytes with and without Li(+), respectively. The MoS2/graphene composite shows a high capacity (225 mA h g(-1)) and great cyclic stability in the Li(+)-containing APC electrolyte.

In situ growth of hollow gold-silver nanoshells within porous silica offers tunable plasmonic extinctions and enhanced colloidal stability.

Porous silica-coated hollow gold-silver nanoshells were successfully synthesized utilizing a procedure where the porous silica shell was produced prior to the transformation of the metallic core, providing enhanced control over the structure/composition of the bimetallic hollow core. By varying the reaction time and the precise amount of gold salt solution added to a porous silica-coated silver-core template solution, composite nanoparticles were tailored to reveal a readily tunable surface plasmon resonance that could be centered across the visible and near-IR spectral regions (∼445-800 nm). Characterization by X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, scanning electron microscopy, and transmission electron microscopy revealed that the synthetic methodology afforded particles having uniform composition, size, and shape.

Surface-engineered growth of AgIn₅S₈ crystals.

The growth of semiconductor crystals and thin films plays an essential role in industry and academic research. Considering the environmental damage caused by energy consumption during their fabrication, a simpler and cheaper method is desired. In fact, preparing semiconductor materials at lower temperatures using solution chemistry has potential in this research field.

Reduced colloidal repulsion imparted by adsorbed polymer of particle dimensions.

This work investigated the detailed interparticle interactions in a concentrated polymer-coated colloidal system in which the bare colloidal particles and the adsorbed polymers are of comparable size and, hence, the polymer adsorption cannot be foreseen to induce repulsive or attractive interactions. Specifically, poly(ethylene oxide) (PEO) chains (R(g) approximately 10nm) adsorbed onto fine silica colloidal particles (SAXS-determined radius approximately 7.4nm; width of log-normal size distribution approximately 0.

Patterned networks of mouse hippocampal neurons on peptide-coated gold surfaces.

Patterned networks of hippocampal neurons were generated on peptide-coated gold substrates prepared by microscope projection photolithography and microcontact printing. A 19 amino acid peptide fragment of laminin A (PA22-2) that includes the IKVAV cell adhesion domain was used to direct patterns of cell adhesion in primary culture. Microscale grid patterns of peptide were deposited on gold-coated glass cover slips by soft lithography using "stamps" fashioned from polydimethylsiloxane.