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A flexible electrochemical sensor was prepared by fabricating nano-zinc oxide and nanopalladium particles on the surface of carbon cloth (CC), which could be used to detect glucose (Glu) and ethanol (Eth) at the same time. This was of great significance to detect the false hypoglycemia caused by the increase of ethanol content. The uniform dispersion of modifiers on the matrix significantly improved the detection sensitivity of the analyte. Further experimental results showed that the constructed sensor displayed good analytical performance in Glu sensing, with a limit of detection (LOD) of 5.20 × 10−7 M (S/N = 3) and a linear range from 1.0 × 10−6 to 1.0 × 10−2 M. The sensor could also detect Eth with LOD was 1.17 × 10−8 M and a wide linear range of 1.0 × 10−7 to 1.0 × 10−3 M was obtained. Moreover, this sensor exhibited good selectivity in the presence of interfering substances such as methanol (MT), isopropanol (IPA), and l-cysteine (L-Cys). Finally, this sensor could be used to detect Glu and Eth in actual blood samples with recoveries of 96.0–106.7%. In conclusion, this work provided a promising way for sensitive simultaneous detection of Glu and Eth. [ABSTRACT FROM AUTHOR]

[Display omitted] • This work confirms that the isolated –OH groups are the nucleation sites of Pt ALD. • The carbonates on the surface of γ-Al 2 O 3 are explored to be not impurities as always considered. The removal of carbonates during the thermal treatment is able to induce the generation of isolated –OH groups. It is crucial to attain a sufficient surface distribution density of metal nanoparticles to achieve high catalytic performance in oxide-supported metal catalysts. Atomic layer deposition (ALD) is a powerful technique for preparing supported nanocatalysts to precisely regulate the metal particle size, structure and distribution in nanoscale. Not only suitable ALD deposition parameters, but also supports with sufficient ALD nucleation sites on the surface are required when using ALD to synthesize supported metal particles with ultrafine size and ultrahigh density. How to regulate the surface nucleation sites to acquire metal nanoparticles with high surface density and elucidating the mechanism are of great importance. Herein, we present a simple thermal treatment approach to activate the surface of γ-Al 2 O 3 , significantly enhancing the Pt loading and the density of Pt nanoparticles compared to raw γ-Al 2 O 3 under identical deposition conditions. Detailed mechanism investigations reveal that removing carbonates on the surface of γ-Al 2 O 3 during thermal treatment induces the generation of isolated –OH groups, which are verified to be nucleation sites of Pt ALD. The increase in the number of isolated –OH and its high reactivity towards anchoring Pt precursor molecules in ALD reaction both contribute to a high density of Pt nanoparticles. This work provides a novel approach to promote Pt ALD nucleation on the surface of γ-Al 2 O 3 and an in-depth understanding of the mechanism for the nucleation promotion, which can be applied to other oxide supports. [ABSTRACT FROM AUTHOR]

The oil-soluble MoS 2 nanoparticles were prepared by hydrolysis of cottonseed acidic oil (CAO) and adopted in situ as the catalysts for slurry-phase hydrotreating of CAO to produce bio-hydrogenated diesel (BHD). The catalytic performance of MoS 2 nanoparticles was evaluated and correlated with their morphological characteristics. The results demonstrated that the particle size and morphology of MoS 2 nanoparticles were obviously dependent on the sulfurization temperature during preparation. The nanoparticles prepared at lower temperature, such as 240 °C (MoS 2 -240), had excellent dispersion in CAO, and their average particle size was 169 nm, exhibiting mono-slabs or double-slabs with an average slab length of 6.1 nm. The catalytic performance of MoS 2 nanoparticles showed a good correlation with their dispersion. The CAO conversion of 98 w% and the BHD yield of more than 82 w% were obtained at a MoS 2 -240 dosage of 500 μg/g, a reaction temperature of 380 °C, an initial H 2 pressure of 5 MPa, and a residence time of 1 h. • Oil-soluble MoS 2 were applied in slurry-phase hydrotreating to produce BHD. • Average size of MoS 2 -240 was 168.9 nm, showing double-slabs with length of 6.1 nm. • Catalytic performance of MoS 2 showed a good correlation with their dispersion. • Conversion of 98 % and BHD yield of 82 % were obtained at MoS2 dosage of 500 μg/g. [ABSTRACT FROM AUTHOR]

Photoelectrochemical reduction of CO2 to value‐added chemicals and fuels is an attractive strategy to store renewable energy and mitigate greenhouse gas emissions. In this study, based on the density functional theory (DFT) calculation, a two‐dimensional nanostructure MoS2 loaded on SnO2 nanoparticles (MS/SON) was prepared for photoassisted electrocatalytic reduction of CO2 to HCOOH through a two‐step process of facile hydrothermal and pyrolysis method. Through physical structure characterization and photoelectric performance test, the results indicated that the 5 % MS/SON exhibits exclusive HCOOH selectivity, the maximum FE is 43.8 %, the current density reached to 9 mA cm−2 at −1.4 V and the photocurrent value is 12.5 μA cm−2 under 0.5 V bias. The overpotential is as low as 245 mV. Besides, after the introduction of MoS2, there is a red shift in the adsorption band edge from 380 nm to 500 nm, indicating an enhancement of light response; the peak intensity of photoluminescence (PL) decreased, showing that the electron and hole are effectively separated; the values of electrochemical impedance spectroscopy (EIS) and Tafel plots (70 mV dec−1) were smaller than other ratios, demonstrating that the faster charge transfer rate; the proper introduction of MoS2 increased the specific surface area from 47.64 m2 g−1 to 55.99 m2 g−1, which was helpful to expand the number of active sites. It is demonstrated that MS/SON is an excellent CO2 reduction material. [ABSTRACT FROM AUTHOR]

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Photoelectrochemical nitrogen reduction (PEC NRR) provides a clean and sustainable method for the production of NH 3 under environmental conditions. However, low reaction efficiency remains a major challenge due to the presence of competitive hydrogen evolution reactions (HER). Herein, nanocomposites (SNP/MSO) with three-phase interface were prepared by loading hydrophilic SnO 2 nanoparticles (SNP) on hydrophobic MoS 2 (MSO) obtained by surface modification with silicomolybdic acid. The hydrophobic interface eliminated the transport barrier of N 2 in the liquid phase to the reaction center, inhibiting HER since the lowered contact area with the liquid proton. Meanwhile, the heterojunction structure formed between MSO and SNP accelerated the effective electron transfer. The synergistic effect of the triphase interface structure and electron transfer structure contributed to the high NH 3 yield (19.6 μg h−1 mg−1) and FE (40.34%) of SNP/10MSO in the photoelectrochemical system. Compared with the nanocomposites (SNP/MSI) prepared by hydrophilic MoS 2 , FE was significantly increased by 10 percentage points. [Display omitted] Three-phase interface of SNP/MSO enhance photoelectrochemical N 2 reduction. [ABSTRACT FROM AUTHOR]

Ideal heterogeneous tandem catalysts necessitate the rational design and integration of collaborative active sites. Herein, we report on the synthesis of a new tandem catalyst with multiple metal-oxide interfaces based on a tube-in-tube nanostructure using template-assisted atomic layer deposition, in which Ni nanoparticles are supported on the outer surface of the inner Al2O3 nanotube (Ni/Al2O3 interface) and Pt nanoparticles are attached to the inner surface of the outer TiO2 nanotube (Pt/TiO2 interface). The tandem catalyst shows remarkably high catalytic efficiency in nitrobenzene hydrogenation over Pt/TiO2 interface with hydrogen formed in situ by the decomposition of hydrazine hydrate over Ni/Al2O3 interface. This can be ascribed to the synergy effect of the two interfaces and the confined nanospace favoring the instant transfer of intermediates. The tube-in-tube tandem catalyst with multiple metal-oxide interfaces represents a new concept for the design of highly efficient and multifunctional nanocatalysts. [ABSTRACT FROM AUTHOR]

Metal-support interfaces play a prominent role in heterogeneous catalysis. However, tailoring the metal-support interfaces to realize full utilization remains a major challenge. In this work, we propose a graceful strategy to maximize the metal-oxide interfaces by coating confined nanoparticles with an ultrathin oxide layer. This is achieved by sequential deposition of ultrathin Al2O3 coats, Pt, and a thick Al2O3 layer on carbon nanocoils templates by atomic layer deposition (ALD), followed by removal of the templates. Compared with the Pt catalysts confined in Al2O3 nanotubes without the ultrathin coats, the ultrathin coated samples have larger Pt-Al2O3 interfaces. The maximized interfaces significantly improve the activity and the protecting Al2O3 nanotubes retain the stability for hydrogenation reactions of 4-nitrophenol. We believe that applying ALD ultrathin coats on confined catalysts is a promising way to achieve enhanced performance for other catalysts. [ABSTRACT FROM AUTHOR]

The reported metal–organic framework (MOF) catalyst realizes CO2 to methanol transformation under ambient conditions. The MOF is one rare example containing metal‐free N‐heterocyclic carbene (NHC) moieties, which are installed using an in situ generation strategy involving the incorporation of an imidazolium bromide based linker into the MOF by postsynthetic ligand exchange. Importantly, the resultant NHC‐functionalized MOF is the first catalyst capable of performing quantitative hydrogen transfer from silanes to CO2, thus achieving quantitative (>99 %) methanol yield. Density‐functional theory calculations indicate the high catalytic activity of the NHC sites in MOFs are attributed to the decreased reaction barrier of a reaction route involving the formation of an NHC‐silane adduct. In addition, the MOF‐immobilized NHC catalyst shows enhanced stability for up to eight cycles without base activation, as well as high selectivity towards the desired silyl methoxide product. [ABSTRACT FROM AUTHOR]