A facile avenue to synthesize bimetallic PdPt nanowire networks with tunable composition and enhanced electrocatalytic performance is demonstrated.

A three‐tiered cake‐style composite is elaborately established, with the characteristic of a double‐deck of MoS2 nanosheets and reduction of graphene oxide (RGO) sheets dotted with CoS2 nanoparticles (CoS2@MoS2/RGO). Because of the prominent synergistic effect of graphene acting as conductive support, MoS2 and CoS2 providing abundant catalytically active sites, and the cake‐style structure promoting mechanical stability, the CoS2@MoS2/RGO exhibits a superior hydrogen evolution reaction activity with a small overpotential of 98 mV at cathodic current density of 10 mA cm−2, and a small Tafel slope of 37.4 mV dec−1, as well as excellent cycling stability. Density functional theory calculations reveal that the hydrogen adsorption free energy of CoS2@MoS2/RGO is close to zero.

Glutathione (GSH) plays crucial roles in various biological functions, the level alterations of which have been linked to varieties of diseases. Herein, we for the first time expanded the application of oxidase-like property of MnO nanosheet (MnO NS) to fluorescent substrates of peroxidase. Different from previously reported fluorescent quenching phenomena, we found that MnO NS could not only largely quench the fluorescence of highly fluorescent Scopoletin (SC) but also surprisingly enhance that of nonfluorescent Amplex Red (AR) via oxidation reaction. If MnO NS is premixed with GSH, it will be reduced to Mn and lose the oxidase-like property, accompanied by subsequent increase in SC's fluorescence and decrease in AR's. On the basis of the above mechanism, we construct the first MnO NS-based ratiometric fluorescent sensor for ultrasensitive and selective detection of GSH. Notably, this ratiometric sensor is programmed by the cascade logic circuit (an INHIBIT gate cascade with a 1 to 2 decoder). And a linear relationship between ratiometric fluorescent intensities of the two substrates and logarithmic values of GSH's concentrations is obtained. The detection limit of GSH is as low as 6.7 nM, which is much lower than previous ratiometric fluorescent sensors, and the lowest MnO NS-based fluorescent GSH sensor reported so far. Furthermore, this sensor is simple, label-free, and low-cost; it also presents excellent applicability in human serum samples.

We demonstrate that nickel-palladium hollow nanoparticles (NiPd hNPs) exhibit triple-enzyme mimetic activity: oxidase-like activity, peroxidase-like activity and catalase-like activity. As peroxidase mimetics, the catalytic activity of NiPd hNPs was investigated in detail. On this basis, a simple glucose biosensor with a wide linear range and low detection limit was developed.

The CoS2/CoSe2 hybrid catalyst exhibits superior HER electrocatalytic activity as well as excellent electrochemical durability. CoSe2/DETA nanobelts not only afford an interconnected conducting network, but also demonstrate superior HER electrocatalytic activity. High dispersion and smaller CoS2 nanoparticles on the surface can provide abundant active sites for the HER.

In this work, we synthesized a novel hybrid catalyst (CoB/CoSe) by growing amorphous CoB on the surface of CoSe nanosheets. Benefiting from the prominent coupled effects between CoB and CoSe nanosheets, an efficient oxygen evolution reaction catalyst CoB/CoSe exhibits a very low overpotential of 320 mV @ 10 mA cm with a Tafel slope of 56.0 mV dec in alkaline medium. An overpotential of 300 mV can also be achieved by CoB/CoSe at the same condition for hydrogen evolution reaction. Notably, at the applied potential of 1.73 V, the electrocatalyst CoB/CoSe demonstrates a current density of 10 mA cm for overall water splitting and displays an outstanding long-term stability. The faradaic efficiencies of CoB/CoSe for both hydrogen and oxygen evolution are close to 100%.

Designing a semiconductor‐based heterostructure photocatalyst for achieving the efficient separation of photogenerated electron‐hole pairs is highly important for enhancing H2 releasing photocatalysis. Here, a new class of Ni1−xCoxSe2–C/ZnIn2S4 hierarchical nanocages with abundant and compact ZnIn2S4 nanosheets/Ni1−xCoxSe2C nanosheets 2D/2D hetero–interfaces, is designed and synthesized. The constructed heterostructure photocatalyst exposes rich hetero‐junctions, supplying the broad and short transfer paths for charge carriers. The close contacts of these two kinds of nanosheets induce a strong interaction between ZnIn2S4 and Ni1−xCoxSe2C, improving the separation and transfer of photo‐generated electron‐hole pairs. As a consequence, the distinctive Ni1−xCoxSe2C/ZnIn2S4 hierarchical nanocages without using additional noble‐metal cocatalysts, display remarkable H2‐relaesing photocatalytic activity with a rate of 5.10 mmol g−1 h−1 under visible light irradiation, which is 6.2 and 30 times higher than those of fresh ZnIn2S4 nanosheets and bare Ni1−xCoxSe2C nanocages, respectively. Spectroscopic characterizations and theory calculations reveal that the strong interaction between ZnIn2S4 and Ni1−xCoxSe2C 2D/2D hetero‐interfaces can powerfully promote the separation of photo‐generated charge carriers and the electrons transfer from ZnIn2S4 to Ni1−xCoxSe2C.

In this work, by utilizing galvanic replacement reaction, a simple method for the synthesis of trimetallic PtCuCo hollow nanospheres with a dendritic shell is demonstrated. The compositions of the nanospheres can be well controlled, and the electrocatalytic activity can also be modulated by adjusting their compositions. Electrocatalytic results show that all of the as-prepared trimetallic PtCuCo nanomaterials show better catalytic performance toward ethylene glycol electrooxidation than the commercial catalyst.