Experimental and Theoretical Insights into Single Atoms, Dual Atoms, and Sub-Nanocluster Catalysts for Electrochemical CO Reduction (CORR) to High-Value Products.

Electrocatalytic carbon dioxide (CO) conversion into valuable chemicals paves the way for the realization of carbon recycling. Downsizing catalysts to single-atom catalysts (SACs), dual-atom catalysts (DACs), and sub-nanocluster catalysts (SNCCs) has generated highly active and selective CO transformation into highly reduced products. This is due to the introduction of numerous active sites, highly unsaturated coordination environments, efficient atom utilization, and confinement effect compared to their nanoparticle counterparts.

Theoretically Designed CuSn-Cu-SnO as Three-Component Electrocatalyst for Efficient and Tunable CO Reduction to Syngas.

Electrocatalytic transformation of CO to various syngas compositions is an exceedingly attractive approach to carbon-neutral recycling. Meanwhile, the achievement of selectivity, stability, and tunability of product ratios using single-component electrocatalysts is challenging. Herein, the theoretically-assisted design of the triple-component nanocomposite electrocatalyst CuSn-Cu-SnO that addresses this challenge is presented.

Metal-Organic Framework-Derived ZnO, N Dually Doped Nanocages as an Efficient Host for Stable Li Metal Anodes.

The drastic volume expansion and dendrite growth of lithium metal anodes give rise to poor electrochemical reversibility. Herein, ZnO, N dually doped nanocages (c-ZNCC) were synthesized as the host for lithium metal anodes using the zeolitic imidazolate framework-8 (ZIF-8). The synthesis is based on a two-step core@shell evolution mechanism, which could guide lithium deposition rapidly and offer a fast lithium-ion diffusion during the cycling process.

Insights into Electrochemical CO Reduction on SnS : Main Product Switch from Hydrogen to Formate by Pulsed Potential Electrolysis.

Tin disulfide (SnS ) is a promising candidate for electrosynthesis of CO -to-formate while the low activity and selectivity remain a great challenge. Herein, we report the potentiostatic and pulsed potential CO RR performance of SnS nanosheets (NSs) with tunable S-vacancy and exposure of Sn-atoms or S-atoms prepared controllably by calcination of SnS at different temperatures under the H /Ar atmosphere. The catalytic activity of S-vacancy SnS (V -SnS ) is improved 1.

Janus (Mo/-MoC)@C heterostructure as an efficient electrocatalyst for the hydrogen evolution reaction in acidic and alkaline media.

To explore low-cost, high-efficiency, and noble-metal-free catalysts for electrocatalytic water splitting in both acidic and alkaline media, the metal-metal carbide Janus hierarchical structure comprising Mo and-MoC embedded on a carbon layer (Mo/-MoC)@C is synthesized by a hydrothermal reaction and subsequent low-temperature magnesium thermic process. Systematic characterization by XRD, XPS, Raman scattering, and SEM/TEM reveals the successful formation of metallic Mo and-MoC nanoparticles. The synthesized (Mo/-MoC)@C has a large specific surface area and boasts highly efficient hydrogen evolution reaction activity including low overpotentials of 152 and 171 mV at a current density of 10 mA cmand small Tafel slopes of 51.

Nonleaching Antibacterial Concept Demonstrated by In Situ Construction of 2D Nanoflakes on Magnesium.

In bone implants, antibacterial biomaterials with nonleaching surfaces are superior to ones based on abrupt release because systemic side effects arising from the latter can be avoided. In this work, a nonleaching antibacterial concept is demonstrated by fabricating 2D nanoflakes in situ on magnesium (Mg). Different from the conventional antibacterial mechanisms that depend on Mg release and pH increase, the nanoflakes exert mechanical tension onto the bacteria membranes to destroy microorganisms on contact and produce intracellular stress via physical interactions, which is also revealed by computational simulations.

Recent Advances in Electrocatalytic Hydrogen Evolution Using Nanoparticles.

Hydrogen fuel is considered as the cleanest renewable resource and the primary alternative to fossil fuels for future energy supply. Sustainable hydrogen generation is the major prerequisite to realize future hydrogen economy. The electrocatalytic hydrogen evolution reaction (HER), as the vital step of water electrolysis to H production, has been the subject of extensive study over the past decades.

Photocatalytic water splitting by N-TiO on MgO (111) with exceptional quantum efficiencies at elevated temperatures.

Photocatalytic water splitting is attracting enormous interest for the storage of solar energy but no practical method has yet been identified. In the past decades, various systems have been developed but most of them suffer from low activities, a narrow range of absorption and poor quantum efficiencies (Q.E.

An antibacterial platform based on capacitive carbon-doped TiO nanotubes after direct or alternating current charging.

Electrical interactions between bacteria and the environment are delicate and essential. In this study, an external electrical current is applied to capacitive titania nanotubes doped with carbon (TNT-C) to evaluate the effects on bacteria killing and the underlying mechanism is investigated. When TNT-C is charged, post-charging antibacterial effects proportional to the capacitance are observed.

Development of a novel tridentate ligand for colorimetric detection of Mn based on AgNPs.

A novel tridentate ligand nitrilotris(methylene)tris(1,2,3-triazole)triacetate (NTTTA) has been synthesized by click reaction and followed with ester hydrolysis reaction. The silver nanoparticles (AgNPs) were then modified and stabilized by this ligand, and subsequently been employed for the highly selective and sensitive colorimetric detection of Mn in aqueous solution. The presence of Mn can cause the aggregation of AgNPs, which leads to the color change of the dispersion from yellow to brown, as well as the decrease and red-shift of the surface plasmon resonance absorption.

CuZnSnS/MoS-Reduced Graphene Oxide Heterostructure: Nanoscale Interfacial Contact and Enhanced Photocatalytic Hydrogen Generation.

Hydrogen generation from water using noble metal-free photocatalysts presents a promising platform for renewable and sustainable energy. Copper-based chalcogenides of earth-abundant elements, especially CuZnSnS (CZTS), have recently arisen as a low-cost and environment-friendly material for photovoltaics and photocatalysis. Herein, we report a new heterostructure consisting of CZTS nanoparticles anchored onto a MoS-reduced graphene oxide (rGO) hybrid.

Dominant Factors Governing the Electron Transfer Kinetics and Electrochemical Biosensing Properties of Carbon Nanofiber Arrays.

Carbon-based electrodes have been widely used in electroanalysis for more than half a century, but the factors governing the heterogeneous electron-transfer (HET) rate are still unclear. The effects of the exposed edge plane site density, inherent resistance of the carbon electrode, and adjustable resistors on the HET kinetics of several outer- and inner-sphere redox couples including [Fe(CN)], Ru(NH), Fe, dopamine, ascorbic acid, and uric acid are investigated using three kinds of carbon electrodes composed of core-shell quasi-aligned nanofiber arrays (QANFAs). The internal resistance is found to be a key factor affecting the HET kinetics and electrochemical biosensing properties.

Au Nanoparticles Decorated TiO2 Nanotube Arrays as a Recyclable Sensor for Photoenhanced Electrochemical Detection of Bisphenol A.

A photorefreshable and photoenhanced electrochemical sensing platform for bisphenol A (BPA) detection based on Au nanoparticles (NPs) decorated carbon doped TiO2 nanotube arrays (TiO2/Au NTAs) is described. The TiO2/Au NTAs were prepared by quick annealing of anodized nanotubes in argon, followed by controllable electrodeposition of Au NPs. The decoration of Au NPs not only improved photoelectrochemical behavior but also enhanced electrocatalytic activities of the resulted hybrid NTAs.

Recyclable Non-Enzymatic Glucose Sensor Based on Ni/NiTiO /TiO Nanotube Arrays.

A non-enzymatic amperometric glucose sensor that can be renewed by light irradiation is described. It is composed of Ni/NiTiO /TiO nanotube arrays (NTAs) prepared by a simple hydrothermal treatment of as-anodized TiO NTAs in a nickel acetate solution followed by annealing under H /Ar. The Ni/NiTiO /TiO NTAs exhibit excellent electrocatalytic activity towards glucose oxidation in a 1.

Real-time monitoring of auxin vesicular exocytotic efflux from single plant protoplasts by amperometry at microelectrodes decorated with nanowires.

Recent biochemical results suggest that auxin (IAA) efflux is mediated by a vesicular cycling mechanism, but no direct detection of vesicular IAA release from single plant cells in real-time has been possible up to now. A TiC@C/Pt-QANFA micro-electrochemical sensor has been developed with high sensitivity in detection of IAA, and it allows real-time monitoring and quantification of the quantal release of auxin from single plant protoplast by exocytosis.

Label-free detection of endocrine disrupting chemicals by integrating a competitive binding assay with a piezoelectric ceramic resonator.

A piezoelectric biosensor for detection of endocrine disrupting chemicals (EDCs) was developed by incorporating chemical/biochemical recognition elements on the ceramic resonator surface for competitive binding assays. A facile electrodeposition was employed to modify the sensor surface with Au nanoparticles, which increased the surface area and enhanced the binding capacity of the immobilized probes. Thiol-labeled long chain hydrocarbon with bisphenol A (BPA) as head group was synthesized and self-assembled on the Au nanoparticle surface as the sensing probes, which showed a linear response upon the binding of estrogen receptor (ER-α) ranging from 1 to 30 nM.

Vascular lumen simulation and highly-sensitive nitric oxide detection using three-dimensional gelatin chip coupled to TiC/C nanowire arrays microelectrode.

Reproducing the physiological environment of blood vessels for the in vitro investigation of endothelial cell functions is very challenging. Here, we describe a vascular-like structure based on a three-dimensional (3D) gelatin chip with good compatibility and permeability which is also cost-effective and easy to produce. The controllable lumen diameter and wall thickness enable close mimicking of blood vessels in vitro.

Controllable growth of conical and cylindrical TiO2-carbon core-shell nanofiber arrays and morphologically dependent electrochemical properties.

Quasi-aligned cylindrical and conical core-shell nanofibers consisting of carbon shells and TiO(2) nanowire cores are produced in situ on Ti foils without using a foreign metallic catalyst and template. A cylindrical nanofiber has a TiO(2) nanowire core 30-50 nm in diameter and a 5-10 nm-thick cylindrical carbon shell, while in the conical nanostructure the TiO(2) nanowire core has a diameter of 20-40 nm and the thickness of the carbon shell varies from about 200 nm at the bottom to about 5 nm at the tip. Electrochemical analysis reveals well-defined redox peaks of the [Fe(CN)(6)](3-/4-) redox couple and heterogeneous charge-transfer rate constants of 0.

Recyclable and high-sensitivity electrochemical biosensing platform composed of carbon-doped TiO2 nanotube arrays.

Electrode fouling and passivation are the main reasons for attenuated signals as well as reduced sensitivity and selectivity over time in electrochemical analysis. We report here a refreshable electrode composed of carbon-doped TiO(2) nanotube arrays (C-doped TiO(2)-NTAs), which not only has excellent electrochemical activity for simultaneous determination of 5-hydroxytryptamine and ascorbic acid but also can be easily photocatalytically refreshed to maintain the high selectivity and sensitivity. The C-doped TiO(2)-NTAs are fabricated by rapid annealing of as-anodized TiO(2)-NTAs in argon.

Growth of well-aligned ZnO nanorod arrays on Si substrates by thermal evaporation of Cu-Zn alloy powders.

Well-aligned ZnO nanorod arrays with uniform diameters and lengths have been fabricated on a Si substrate by simple thermal evaporation of Cu-Zn alloy powders in the presence of oxygen without using a template, catalyst, or pre-deposited ZnO seed layer. The ZnO nanorods are characterized by X-ray diffraction, electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy and the growth mechanism is suggested. The nanorods have a single-crystal hexagonal structure and grow along the (0001) direction.

Core-shell TiC/C quasi-aligned nanofiber arrays on biomedical Ti6Al4V for sensitive electrochemical biosensing.

Core-shell TiC/C-QANFAs are produced directly on a Ti6Al4V substrate by a simple thermochemical process that does not require a metal catalyst or template. The nanostructured arrays show Nernstian behavior and fast electron-transfer kinetics in the electrochemical reactions of Fe(CN)(6)(3-/4-) and demonstrate high selectivity and sensitivity in the simultaneous detection of AA, DA, and UA.