On-mask detection of SARS-CoV-2 related substances by surface enhanced Raman scattering.

We have developed a convenient surface-enhanced Raman scattering (SERS) platform based on vertical standing gold nanowires (v-AuNWs) which enabled the on-mask detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) related substances such as the Spike-1 protein and the corresponding pseudo-virus. The Spike-1 protein was clearly distinguished from BSA protein with an accuracy above 99 %, and the detection limit could be achieved down to 0.01 μg/mL.

Smart Contact Lenses for Healthcare Monitoring and Therapy.

The eye contains a wealth of physiological information and offers a suitable environment for noninvasive monitoring of diseases via smart contact lens sensors. Although extensive research efforts recently have been undertaken to develop smart contact lens sensors, they are still in an early stage of being utilized as an intelligent wearable sensing platform for monitoring various biophysical/chemical conditions. In this review, we provide a general introduction to smart contact lenses that have been developed for disease monitoring and therapy.

2D TiS-Nanosheet-Coated Concave Gold Arrays with Triple-Coupled Resonances as Sensitive SERS Substrates.

Herein, a hybrid substrate for surface-enhanced Raman scattering (SERS) is fabricated, which couples localized surface plasmon resonance (LSPR), charge transfer (CT) resonance, and molecular resonance. Exfoliated 2D TiS nanosheets with semimetallic properties accelerate the CT with the tested analytes, inducing a remarkable chemical mechanism enhancement. In addition, the LSPR effect is coupled with a concave gold array located underneath the thin TiS nanosheet, providing a strong electromagnetic enhancement.

Rapid, label-free histopathological diagnosis of liver cancer based on Raman spectroscopy and deep learning.

Biopsy is the recommended standard for pathological diagnosis of liver carcinoma. However, this method usually requires sectioning and staining, and well-trained pathologists to interpret tissue images. Here, we utilize Raman spectroscopy to study human hepatic tissue samples, developing and validating a workflow for in vitro and intraoperative pathological diagnosis of liver cancer.

A miniaturized electrochemical device based on the nitrogen, carbon-codoped bimetal for real-time monitoring of acetaminophen and dopamine in urine.

In-situ real-time detection of drug metabolites and biomolecules in hospitalized patients' urine helps the doctors to monitor their physiological indicators and regulate the use of drug doses. In this work, nitrogen-doped carbon-supported bimetal was prepared into the screen-printed electrodes (SPEs) and applied for real-time monitoring of acetaminophen (AC) and dopamine (DA) in urine. Via one-step pyrolysis of the core-shell cubic precursor (Cu[Co(CN)]@Co[Co(CN)], CuCo@CoCo), the nitrogen-doped carbon-supported bimetal (CuCo-NC) was formed.

Noninvasive Diagnosis of Gastric Cancer Based on Breath Analysis with a Tubular Surface-Enhanced Raman Scattering Sensor.

SERS-based breath analysis as an emerging technique has attracted increasing attention in cancer screening. Here, eight aldehydes and ketones in the human breath are reported as the VOC biomarkers identified by gas chromatography-mass spectrometry (GC-MS) and applied further for the noninvasive diagnosis of gastric cancer (GC) with a tubular SERS sensor. The tubular SERS sensor is prepared with a glass capillary loaded with ZIF-67-coated silver particles (Ag@ZIF-67), which offers Raman enhancement from the plasmonic nanoparticles and gas enrichment from the metal-organic framework (MOF) shells.

Atomically Thin TaSe Film as a High-Performance Substrate for Surface-Enhanced Raman Scattering.

An atomically thin TaSe sample, approximately containing two to three layers of TaSe nanosheets with a diameter of 2.5 cm is prepared here for the first time and applied on the detection of various Raman-active molecules. It achieves a limit of detection of 10  m for rhodamine 6G molecules.

Smart Contact Lens with Dual-Sensing Platform for Monitoring Intraocular Pressure and Matrix Metalloproteinase-9.

Contact lenses have become a popular health-monitoring wearable device due to their direct contact with the eyes. By integrating biosensors into contact lenses, real-time and noninvasive diagnoses of various diseases can be realized. However, current contact lens sensors often require complex electronics, which may obstruct the user's vision or even damage the cornea.

Dopamine Imaging in Living Cells and Retina by Surface-Enhanced Raman Scattering Based on Functionalized Gold Nanoparticles.

Retinal dopamine is believed to be involved in the development of myopia, which is projected to affect almost half of the world population's visual health by 2050. Direct visualization of dopamine in the retina with high spatial precision is essential for understanding the biochemical mechanism during the development of myopia. However, there are very few approaches for the direct detection of dopamine in the visual system, particularly in the retina.

Nesting CoMo Binary Alloy Nanoparticles onto Molybdenum Oxide Nanosheet Arrays for Superior Hydrogen Evolution Reaction.

Transition-metal alloys have attracted a great deal of attention as an alternative to Pt-based catalysts for hydrogen evolution reaction (HER) in alkaline. Herein, a facile and convenient strategy to fabricate CoMo binary alloy nanoparticles nesting onto molybdenum oxide nanosheet arrays on nickel foam is developed. By modulating the annealing time and temperature, the CoMo alloy catalyst displays a superior HER performance.

A general strategy for the functionalization of two-dimensional metal chalcogenides.

Two-dimensional (2D) metal chalcogenides (MC) such as MoS have been recognized as promising materials for near future applications. However, general strategies to functionalize them are still scarce, while the nature of functionalization still remains unclear. Herein, we demonstrate a simple and universal functionalization route through complexation reaction between the amino-containing organic agents and MCs.

Large-scale controlled synthesis of porous two-dimensional nanosheets for the hydrogen evolution reaction through a chemical pathway.

Molybdenum disulfide (MoS2) is an extensively studied promising non-noble catalyst because of its remarkable performance for the hydrogen evolution reaction (HER). However, the primary factors that affect its catalytic activity have not been analysed comprehensively and quantitatively; this impedes the further design and development of MoS2-based electrocatalysts. Herein, using novel porous MoS2 nanosheets prepared via a controlled and scalable KOH-assisted exfoliation pathway, we methodically studied the contributions of bore edge active sites to the catalytic activity towards the HER.

Dual-Functional Starfish-like P-Doped Co-Ni-S Nanosheets Supported on Nickel Foams with Enhanced Electrochemical Performance and Excellent Stability for Overall Water Splitting.

Dual-functional electrocatalysts have recently been reported to improve the conversion and storage of energy generated from overall water splitting in alkaline electrolytes. Herein, for the first time, a shape-controlled synthesis of starfish-like Co-Ni-S nanosheets on three-dimensional (3D) hierarchically porous nickel foams (Co-Ni-S/NF) via a one-step hydrothermal method was developed. The influence of reaction time on the nanosheet structure and properties was intensively studied.

Controlled Electrodeposition Synthesis of Co-Ni-P Film as a Flexible and Inexpensive Electrode for Efficient Overall Water Splitting.

Synthesis of highly efficient and robust catalysts with earth-abundant resources for overall water splitting is essential for large-scale energy conversion processes. Herein, a series of highly active and inexpensive Co-Ni-P films were fabricated by a one-step constant current density electrodeposition method. These films were demonstrated to be efficient bifunctional catalysts for both H and O evolution reactions (HER and OER), while deposition time was deemed to be the crucial factor governing electrochemical performance.

Insight into the hydrogen evolution reaction of nickel dichalcogenide nanosheets: activities related to non-metal ligands.

Transition metal dichalcogenides, MX (M = Fe, Co, Ni, X = S, Se, Te), have been proven to be promising substitutes for noble metals in hydrogen evolution reactions (HERs). However, forthright comparisons of metal sulfides, metal selenides, and metal tellurides are rarely conducted, let alone the mechanism of the important role of their non-metal ligands. In this paper, we report the pilot study of a controllable method for the preparation of a series of NiX (X = S, Se, Te) nanosheets via a facile anion-exchange reaction.

Surface Tension Components Ratio: An Efficient Parameter for Direct Liquid Phase Exfoliation.

Direct liquid phase exfoliation (LPE) is generally regarded as an effective and efficient methodology for preparing single- to few-layered nanosheets on a large scale. Based on a previous finding that the polar and dispersive components of surface tension can be used as critical parameters for screening suitable solvents for LPE, in this study, we conducted in-depth research on direct LPE of two-dimensional (2D) materials by the extensive LPE of a series of 2D materials and the thorough comparison of their surfaces properties and LPE efficiencies. We rationally developed the surface tension component matching (STCM) theory, and in nature, its key point lies in the close ratio of polar to dispersive components (P/D) between the solvents and the aimed 2D materials.

Anion-exchange engineering of cookie-like BiS/BiMoO heterostructure for enhanced photocatalytic activities and gas-sensing properties.

Developing efficient visible-light-driven photocatalysts will advance alternative energy technologies, ultimately curbing the environmental pollution associated with fossil fuels. In this work, BiS/BiMoO photocatalysts with a heterogeneous cookie-like structure were prepared for the first time by in-situ anion exchange at relatively low temperatures. The catalysts exhibited enhanced photocatalytic activity, which we attributed to the photocurrent response, a diminished recombination rate of photogenerated electron-hole pairs, and the existence of a large heterojunction interface.

Insight into In Situ Amphiphilic Functionalization of Few-Layered Transition Metal Dichalcogenide Nanosheets.

A facile route toward functionalized amphiphilic layered transition-metal dichalcogenide nanosheets through in situ polymerization of polystyrene-polyacrylamide copolymers is established. The attachment of copolymers greatly affects their dispersibility in different kinds of solvents. Surface-tension components, polarity, and coordination effects of the copolymer are found to be the main factors affecting the dispersibility.

Cobalt-Doped FeSe2-RGO as Highly Active and Stable Electrocatalysts for Hydrogen Evolution Reactions.

Herein, we describe the preparation and testing of Co-doped FeSe2 hybridized with graphene (Fe1-xCoxSe2/RGO), a high-active yet stable electrocatalyst for hydrogen evolution reactions (HERs) in acidic solutions. First, we systematically analyze the composition and morphology of Fe1-xCoxSe2/RGO and attribute its excellent electrochemical performance to its unique architecture-a base of highly conductive graphene with fully exposed active edges that enhances conductivity and facilitates ion/electron transfer. Our experimental measurements indicate elevated HER activity with a moderate overpotential of ∼166 mV at a hydrogen production current density of 10 mA cm(-2), a small Tafel slope of ∼36 mV dec(-1), and long cycling lifespan more than 20 h.

Facile synthesis of CuCo2S4 as a novel electrode material for ultrahigh supercapacitor performance.

CuCo2S4 nanoparticles demonstrating outstanding electrochemical performances were firstly synthesized through a simple solvothermal approach without using any templates. CuCo2S4 synthesized in glycerol (CuCo2S4-glycerol) fulfills an ultrahigh capacitance of 5030 F g(-1) at 20 A g(-1) in a polysulfide electrolyte.