In Situ Formation of Phosphorescent Molecular Gold(I) Cluster in a Macroporous Polymer Film to Achieve Colorimetric Cyanide Sensing

A highly phosphorescent molecular Au­(I) cluster capable of rapid, sensitive, and selective detection of cyanide has been successfully fabricated. The origin of the outstanding sensing performance of the molecular Au­(I) cluster toward cyanide is justified by X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) analyses. The response mechanism employed with the molecular Au­(I) cluster and the cost-effectiveness in cyanide detection affords several key sensor features, making this molecular Au­(I) cluster-based sensor unique compared to other cyanide sensing schemes. Importantly, by exploring the phosphorescent properties of the molecular Au­(I) cluster in solid state, we demonstrate the first example of the molecular gold­(I) cluster-based macroporous sensing film for colorimetric detection of cyanide in complex samples, including red wine, coffee, juice, and soil. Remarkably, the as-prepared sensing film inherits the sensing ability of the molecular Au­(I) cluster, and offers a high mechanical flexibility and novel opportunities for real-time monitoring cyanide release in cassava manufacturing

Functionalized Nano-MoS₂ with Peroxidase Catalytic and Near-Infrared Photothermal Activities for Safe and Synergetic Wound Antibacterial Applications

We have developed a biocompatible antibacterial system based on polyethylene glycol functionalized molybdenum disulfide nanoflowers (PEG-MoS₂ NFs). The PEG-MoS₂ NFs have high near-infrared (NIR) absorption and peroxidase-like activity, which can efficiently catalyze decomposition of low concentration of H₂O₂ to generate hydroxyl radicals (·OH). The conversion of H₂O₂ into ·OH can avoid the toxicity of high concentration of H₂O₂ and the ·OH has higher antibacterial activity, making resistant bacteria more vulnerable and wounds more easily cured. The PEG-MoS₂ NFs combine the catalysis with NIR photothermal effect, providing a rapid and effective killing outcome <i>in vitro</i> for Gram-negative ampicillin resistant <i>Escherichia coli</i> (Amp^r <i>E. coli</i>) and Gram-positive endospore-forming <i>Bacillus subtilis</i> (<i>B. subtilis</i>) as compared to catalytic treatment or photothermal therapy (PTT) alone. Wound healing results indicate that the synergy antibacterial system could be conveniently used for wound disinfection <i>in vivo</i>. Interestingly, glutathione (GSH) oxidation can be accelerated due to the 808 nm irradiation induced hyperthermia at the presence of PEG-MoS₂ NFs proved by X-ray near-edge absorption spectra and X-ray spectroscopy. The accelerated GSH oxidation can result in bacterial death more easily. A mechanism based on ·OH-enhanced PTT is proposed to explain the antibacterial process

1D/1D Hierarchical Nickel Sulfide/Phosphide Nanostructures for Electrocatalytic Water Oxidation

The sluggish kinetics of the oxygen evolution reaction (OER) limits the efficiencies of solar-powered electrical-conversion applications, such as water splitting and carbon dioxide reduction. Herein, we rationally designed a metallic nanostructured nickel sulfide/phosphide hybrid (NiS_<i>x</i>P_<i>y</i>) as an efficient precatalyst for OER, with one-dimensional (1D) nanowires grown on 1D nanorods. The resulting metallic hybrid NiS_<i>x</i>P_<i>y</i> catalyst can accelerate the electron transfer process and expose abundant in situ-generated NiOOH species during OER (NiS_<i>x</i>P_<i>y</i>–O). Therefore, NiS_<i>x</i>P_<i>y</i>–O exhibits a low overpotential of 192 mV (with 100% <i>iR</i> compensation; this value should be 200 mV without compensation) to achieve an O₂ partial current density (<i>j</i>_O2) of 10 mA cm^–2 and a robust stability over 135 h without obvious degradation. Moreover, a <i>j</i>_O2 of 10 mA cm^–2 at an overpotential of 315 mV (with 100% <i>iR</i> compensation; this value should be 365 mV without compensation) is attained in near-neutral conditions. These results may pave a new way to design metallic precatalysts with 1D/1D hierarchical nanostructures to boost the OER

Bimetallic Carbide as a Stable Hydrogen Evolution Catalyst in Harsh Acidic Water

Cheap, efficient, and stable hydrogen evolution reaction (HER) electrocatalysts have long been pursued, owing to their scientific and technological importance. Currently, platinum has been regarded as the benchmarked HER electrocatalyst. Unfortunately, the low abundance and high cost impede its industrial applications. Here, we synthesize bimetallic carbide Mo₆Ni₆C grown on nickel foam as a HER catalyst, delivering a low overpotential of −51 mV at −10 mA cm^–2 in 0.5 M H₂SO₄ for more than 200 h, which is among the best reported benchmarked HER catalysts in acid to date. On the basis of experimental observations and theoretical modeling, we ascribe the good activity to the proper Gibbs free energy of adsorbed hydrogen (Δ<i>G</i>(H*)) for the carbon active sites and attribute the stability to the corrosion-stable Mo–Mo bonds in the crystal structure. This work demonstrates the possibility for Mo₆Ni₆C to be one of the best candidates for HER electrocatalysts in the large-scale electrolysis industry

Bimetallic Carbide as a Stable Hydrogen Evolution Catalyst in Harsh Acidic Water

Cheap, efficient, and stable hydrogen evolution reaction (HER) electrocatalysts have long been pursued, owing to their scientific and technological importance. Currently, platinum has been regarded as the benchmarked HER electrocatalyst. Unfortunately, the low abundance and high cost impede its industrial applications. Here, we synthesize bimetallic carbide Mo₆Ni₆C grown on nickel foam as a HER catalyst, delivering a low overpotential of −51 mV at −10 mA cm^–2 in 0.5 M H₂SO₄ for more than 200 h, which is among the best reported benchmarked HER catalysts in acid to date. On the basis of experimental observations and theoretical modeling, we ascribe the good activity to the proper Gibbs free energy of adsorbed hydrogen (Δ<i>G</i>(H*)) for the carbon active sites and attribute the stability to the corrosion-stable Mo–Mo bonds in the crystal structure. This work demonstrates the possibility for Mo₆Ni₆C to be one of the best candidates for HER electrocatalysts in the large-scale electrolysis industry