Photo-enhanced electrocatalytic hydrogen evolution reaction coupled semiconductor with plasma in neutral solution.

A gold-ruthenium/zinc oxide nanorod composite was synthesized. The electrochemical catalytic efficiency of the noble metal-semiconductor nanostructure increased by nearly 30% under the irradiation of an external light source. It provides an efficient way of thinking for the design of electrocatalysts with a photoresponse.

How Stabilizers and Reducing Agents Affect the Formation of Nanogold Amalgams.

The influence of mercury on the morphology and formation mechanism of gold amalgams in the presence of different reducing agents (ascorbic acid and sodium borohydride) was systematically studied. In the presence of cetyltrimethylammonium bromide (CTAB), chemical reducing agents not only reduced mercury ions in the solution but also replaced the CTAB molecules on the surface of the gold nanorod. The stability of the reducing agents in the colloidal system and the combining capacity of the reducing agent to the gold nanoparticles can affect the alloying process of mercury and gold, thereby forming a rod-shaped or spherical gold amalgam.

Chitosan-sodium alginate-based coatings for self-strengthening anticorrosion and antibacterial protection of titanium substrate in artificial saliva.

A self-strengthening coating with silver nanoparticles (Ag NPs) doped chitosan (CHI) and sodium alginate (SA) polyelectrolytes was constructed on the surface of polydopamine (PDA) coated Ti substrate by a layer-by-layer assembly method. The PDA coating exhibited an excellent bond with Ti substrate, and also can uniformly deposit Ag NPs via a mild method without introducing any exogenous reductant. The CHI coating was assembled through a spin-coating method for controlling Ag release.

Molybdenum-containing polypyrrole self-supporting hollow flexible electrode for hydrogen peroxide detection in living cells.

A flexible electrode based on polypyrrole-supported free-standing molybdenum oxide-molybdenum disulfide/polypyrrole nanostructure (MoO-MoS/PPy) was synthesized. The petal-like MoO-MoS sheets grown on PPy were prepared step by step through simple electrodeposition and hydrothermal methods. The corresponding surface morphological and structural characterizations were characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS).

Hollow Multiple Noble Metallic Nanoalloys by Mercury-Assisted Galvanic Replacement Reaction for Hydrogen Evolution.

Hollow multimetallic noble nanoalloys with high surface area/volume ratio, abundant active sites, and relatively effective catalytic activity have attracted considerable research interest. Traditional noble nanoalloys fabricated by hydro-/solvothermal methods usually involve harsh synthetic conditions such as high temperatures and intricate processing. We proposed a simple and mild strategy to synthesize platinum- and palladium-decorated hollow gold-based nanoalloys by the galvanic replacement reaction (GRR) at room temperature using hollow gold nanoparticles as templates and mercury as an intermediate.

Bismuth-induced synthesis of Au-X (X = Pt, Pd) nanoalloys for electrocatalytic reactions.

Bismuth was introduced as an intermediate to produce Au-X (X = Pt and Pd) bimetallic nanoalloys using the galvanic replacement reaction. The results showed that the Au-X nanoalloys have good activity for electrocatalytic reactions in alkaline media. This strategy can provide an option for the formation of multimetal nanoalloys with similar electrochemical potentials and compositions.

Electrochemical endotoxin aptasensor based on a metal-organic framework labeled analytical platform.

An electrochemical aptasensor for the lipopolysaccharide (LPS) detection was constructed by using copper-based metal-organic framework (Cu-MOF) as a label and the LPS aptamer of specific single-stranded DNA as a probe. The carboxyl-functionalized polypyrrole nanowires (PPy NWs) were synthesized by electrochemical polymerization method, and the amino-terminated aptamer covalently coupling with the carboxyl group of the PPy NWs was immobilized onto the modified electrode. The aptamer can specifically combine with the target LPS molecules, and Cu-MOF was labeled by adsorption based on specific interactions of LPS carbohydrate portions with anionic groups.

Spectroscopic evidence for electrochemical effect of mercury ions on gold nanoparticles.

We demonstrated an interesting phenomenon that the electrochemical reduction of mercury ions (Hg) caused distinctly different morphology of gold nanorods (Au NRs) depending on the concentration of Hg. Specifically, in the case of low concentration, mercury formed through electrochemical reduction only deposited onto the gold surface, and then could be reversibly removed from the gold surface by electrochemical stripping process without causing obvious changes of Au NRs in shape and size. But in the case of high concentration, the reduced Hg not only deposited onto the gold surface but also entered into the interior of Au NRs making them change into gold nanospheres (Au NSs) in an irreversible manner due to the alloying effect of gold with Hg.

Copper ion-assisted gold nanoparticle aggregates for electrochemical signal amplification of lipopolysaccharide sensing.

A signal amplification electrochemical aptasensor for ultrasensitive detection of lipopolysaccharide (LPS) was fabricated. The sensor was constructed with a probe of LPS aptamer and a copper ions-mediated gold nanoparticles aggregate (Cu/Au NA) as a signal amplification material. The Cu/Au NAs comprising copper ions (Cu) and L-cysteine modified AuNPs were fabricated by a self-assembly process.

High rate and stable symmetric potassium ion batteries fabricated with flexible electrodes and solid-state electrolytes.

Aqueous batteries designed with K-ions have outstanding potential for future energy storage applications. When coupled with cathode and anode materials both operating with the intercalation mechanism, K-ion batteries could have kinetics and stability similar to Li-ion batteries in principle but with a much lower cost. However, the electrode materials developed so far still suffer from poor stability and limited activity, especially from the anode side.

Continuous wave and ReS passively Q-switched Er : SrF laser at ∼3 μm.

We report on an efficient Er:SrF laser at 2.79 μm. A continuous wave output power of 1.

A rechargeable iodine-carbon battery that exploits ion intercalation and iodine redox chemistry.

Graphitic carbons have been used as conductive supports for developing rechargeable batteries. However, the classic ion intercalation in graphitic carbon has yet to be coupled with extrinsic redox reactions to develop rechargeable batteries. Herein, we demonstrate the preparation of a free-standing, flexible nitrogen and phosphorus co-doped hierarchically porous graphitic carbon for iodine loading by pyrolysis of polyaniline coated cellulose wiper.

3 D Porous Nickel-Cobalt Nitrides Supported on Nickel Foam as Efficient Electrocatalysts for Overall Water Splitting.

Exploring highly efficient and durable bifunctional electrocatalysts from earth-abundant low-cost transition metals is central to obtaining clean hydrogen energy through large-scale electrolytic water splitting. Porous nickel-cobalt nitride nanosheets on macroporous Ni foam (NF) are synthesized through facile electrodeposition followed by a one-step annealing process in a NH atmosphere. The transformation from a metal hydroxide into a metal nitride could efficiently enhance the electrocatalytic performance for both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER).

Determination of copper ions using a phytic acid/polypyrrole nanowires modified glassy carbon electrode.

This study reports a sensitive electro-analytical method for the determination of trace amounts of Cu using a phytate functionalized polypyrrole nanowires (PPy NWs) modified glass carbon electrode. The phytic acid/polypyrrole (PA/PPy) NWs were prepared by an electrostatic adsorption and ultrasonic mixing. The results showed that both PPy NWs and PA/PPy NWs modified glassy carbon electrodes have electrochemical responses toward Cu.

Transition metal ions regulated oxygen evolution reaction performance of Ni-based hydroxides hierarchical nanoarrays.

Nickel-based hydroxide hierarchical nanoarrays (NiM(OH) HNAs M = Fe or Zn) are doped with non-noble transition metals to create nanostructures and regulate their activities for the oxygen evolution reaction. Catalytic performance in these materials depends on their chemical composition and the presence of nanostructures. These novel hierarchical nanostructures contain small secondary nanosheets that are grown on the primary nanowire arrays, providing a higher surface area and more efficient mass transport for electrochemical reactions.

Temperature-dependent surface nanomechanical properties of a thermoplastic nanocomposite.

In polymer nanocomposites, particle-polymer interactions influence the properties of the matrix polymer next to the particle surface, providing different physicochemical properties than in the bulk matrix. This region is often referred to as the interphase, but detailed characterization of its properties remains a challenge. Here we employ two atomic force microscopy (AFM) force methods, differing by a factor of about 15 in probing rate, to directly measure the surface nanomechanical properties of the transition region between filler particle and matrix over a controlled temperature range.

Graphitic CN as a new saturable absorber for the mid-infrared spectral range.

The saturable absorption properties of few-layer graphitic carbon nitride (g-CN) nanosheets near 3 μm were investigated. A stable Q-switched Er:LuO laser at 2.84 μm was realized by using a home-made g-CN saturable absorber (SA), generating a pulse duration of 351 ns and an average output power of 1.

Synthesis of a novel electrode material containing phytic acid-polyaniline nanofibers for simultaneous determination of cadmium and lead ions.

The development of nanostructured conducting polymers based materials for electrochemical applications has attracted intense attention due to their environmental stability, unique reversible redox properties, abundant electron active sites, rapid electron transfer and tunable conductivity. Here, a phytic acid doped polyaniline nanofibers based nanocomposite was synthesized using a simple and green method, the properties of the resulting nanomaterial was characterized by electrochemical impedance spectroscopy (EIS), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). A glassy carbon electrode modified by the nanocomposite was evaluated as a new platform for the simultaneous detection of trace amounts of Cd and Pb using differential pulse anodic stripping voltammetry (DPASV).

Cation Intercalation in Manganese Oxide Nanosheets: Effects on Lithium and Sodium Storage.

The rapid development of advanced energy-storage devices requires significant improvements of the electrode performance and a detailed understanding of the fundamental energy-storage processes. In this work, the self-assembly of two-dimensional manganese oxide nanosheets with various metal cations is introduced as a general and effective method for the incorporation of different guest cations and the formation of sandwich structures with tunable interlayer distances, leading to the formation of 3D Mx MnO2 (M=Li, Na, K, Co, and Mg) cathodes. For sodium and lithium storage, these electrode materials exhibited different capacities and cycling stabilities.

General Preparation of Three-Dimensional Porous Metal Oxide Foams Coated with Nitrogen-Doped Carbon for Enhanced Lithium Storage.

Porous metal oxide architectures coated with a thin layer of carbon are attractive materials for energy storage applications. Here, a series of porous metal oxide (e.g.

Watt-level passively Q-switched Er:Lu₂O₃ laser at 2.84 μm using MoS₂.

Efficient diode-pumped passively Q-switched Er:Lu2O3 laser operation at 2.84 μm was realized. A few-layer MoS2 nanosheet film on a YAG substrate, was fabricated and employed as saturable absorber (SA) in a short plane-plane cavity.

Functionalized gold nanoparticles/reduced graphene oxide nanocomposites for ultrasensitive electrochemical sensing of mercury ions based on thymine-mercury-thymine structure.

A sensitive, selective and reusable electrochemical biosensor for the determination of mercury ions (Hg(2+)) has been developed based on thymine (T) modified gold nanoparticles/reduced graphene oxide (AuNPs/rGO) nanocomposites. Graphene oxide (GO) was electrochemically reduced on a glassy carbon substrate. Subsequently, AuNPs were deposited onto the surface of rGO by cyclic voltammetry.

Excellent anti-corrosive pretreatment layer on iron substrate based on three-dimensional porous phytic acid/silane hybrid.

A novel, highly effective and environmentally friendly film-forming material, phytic acid (PA)/silane (denoted as PAS) hybrid with a three-dimensional (3D) network structure, was prepared through a condensation reaction of PA with methyltrihydroxysilane generated from the hydrolysis of methyltriethoxysilane (MTES). Two kinds of PAS-based pretreatment layers, namely NaBrO3-free and NaBrO3-doped PAS layers, were fabricated on iron substrates using the dip-coating method. SEM and AFM observations showed that the as-fabricated PAS-based layers possessed a 3D porous microstructure at the nanoscale and a rough surface morphology.

Surface modification of Pt(100) for electrocatalytic nitrate reduction to dinitrogen in alkaline solution.

Nitrate reduction on a Pt(100) electrode modified by Cu (Cu/Pt(100)) and Rh (Rh/Pt(100)) adatoms have been studied in alkaline media by means of cyclic voltammetry and in situ online electrochemical mass spectrometry (OLEMS). According to the cyclic voltammograms, nitrate reduction is catalyzed by both Cu/Pt(100) and Rh/Pt(100). Ammonia is the main product on the Rh/Pt(100) electrode in alkaline media.

Electrochemical behavior and voltammetric determination of acetaminophen based on glassy carbon electrodes modified with poly(4-aminobenzoic acid)/electrochemically reduced graphene oxide composite films.

Poly(4-aminobenzoic acid)/electrochemically reduced graphene oxide composite film modified glassy carbon electrodes (4-ABA/ERGO/GCEs) were fabricated by a two-step electrochemical method. The electrochemical behavior of acetaminophen at the modified electrode was investigated by means of cyclic voltammetry. The results indicated that 4-ABA/ERGO composite films possessed excellent electrocatalytic activity towards the oxidation of acetaminophen.