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Alpha alumina (α‐Al2O3) are inert materials with outstanding thermal, chemical and mechanical stability. Herein, we fabricate porous single‐crystalline (PSC) α‐Al2O3 monoliths at centimeter scale to endow them with high catalytic activity while maintaining their stability. We reduce PSC α‐Al2O3 monoliths to create oxygen vacancies in lattice and stabilize them by the ordered lattice to construct unsaturated Al−O coordination structures for enhancing the catalytic activity. The generation of oxygen vacancy at 18e wyckoff position contributes to the unsaturated Al−O coordination. As a case study, we demonstrate the outstanding performance with conversion (≈34 %) and selectivity (≈95 %) toward non‐oxidative dehydrogenation of ethane to ethylene at 700 °C. We achieve the outstanding performance without obvious degradation even after a continuous operation over 1000 hours at 700 °C. [ABSTRACT FROM AUTHOR]

Alpha alumina (α‐Al2O3) are inert materials with outstanding thermal, chemical and mechanical stability. Herein, we fabricate porous single‐crystalline (PSC) α‐Al2O3 monoliths at centimeter scale to endow them with high catalytic activity while maintaining their stability. We reduce PSC α‐Al2O3 monoliths to create oxygen vacancies in lattice and stabilize them by the ordered lattice to construct unsaturated Al−O coordination structures for enhancing the catalytic activity. The generation of oxygen vacancy at 18e wyckoff position contributes to the unsaturated Al−O coordination. As a case study, we demonstrate the outstanding performance with conversion (≈34 %) and selectivity (≈95 %) toward non‐oxidative dehydrogenation of ethane to ethylene at 700 °C. We achieve the outstanding performance without obvious degradation even after a continuous operation over 1000 hours at 700 °C. [ABSTRACT FROM AUTHOR]

Molybdenum carbide-based hydrogen evolution reaction (HER) electrocatalysts have attracted widespread attention with their low cost and relatively high catalytic activity. Despite the significant progress made in tuning the morphology and structure, the intrinsic catalytic activity of molybdenum carbide awaits further improvement. Herein, a Pt-decorated self-supported MoC-Mo 2 C electrode with super-intrinsic HER catalytic activity is prepared by a simple adsorption-electroreduction method. The HER performance is improved with increasing the loading of Pt. The optimal MoC-Mo 2 C-Pt heterojunction electrode has a low overpotential of 10 mA cm−2 (58 mV in H 2 SO 4 , 82 mV in KOH) and small Tafel slope (24 mV dec−1 in H 2 SO 4, 29 mV dec−1 in KOH), which is reduced to 0.45–0.5, 0.7–0.8, and 0.4–0.7 times of pristine MoC-Mo 2 C, Pt foil, and commercial Pt/C (2 mg cm−2), respectively. The improved HER catalysis is attributed to the rapid dissociation of water on MoC-Mo 2 C and efficient desorption of hydrogen on Pt. Therefore, decorating carbides with Pt is an effective way to design HER catalysts with enhanced catalytic activities in a wide pH range. [ABSTRACT FROM AUTHOR]

In order to expand the photoresponsive spectrum of TiO 2 and improve its catalytic activity under visible light, the hollow urchin-like composites of TiO 2 @g-C 3 N 4 /GQDs (TCN/GQDs) with a core-shell structure heterojunction was synthesized through a hydrothermal method and calcination. Potassium titanium oxalate, melamine, and citric acid were utilized as the raw materials for this synthesis process. The TCN/GQDs composites were subjected to a range of analyses to examine their microstructure and photoelectric properties. The findings indicated that the synthesized composites effectively enhanced the absorption spectrum of TiO 2 in the visible light range by creating the stable heterojunctions among TiO 2 , g-C 3 N 4 and GQDs. Additionally, the ability of these composites to degrade toxic organic pollutants under visible light was studied by using several different organic dyes and antibiotics. The results demonstrated that the TCN/GQDs composites exhibited efficient visible light catalytic degradation capability on organic pollutants, and the degradation efficiency could approach to 100 % under visible light in a short time. Furthermore, the photocatalyst exhibited hardly change of degradation efficiency towards organic pollutants even after 5 cycles of testing, suggesting its commendable performance in visible light catalysis and potential for repeated utilization. [ABSTRACT FROM AUTHOR]

In this paper, mesoporous Cu 2 O–CeO 2 nanospheres were fabricated via a facile, low-temperature solution route in the presence of poly(2-vinylpyridine)- b -poly(ethylene Oxide) (P2VP- b -PEO) block copolymers. The prepared mesoporous Cu 2 O–CeO 2 nanospheres were characterized systematically by scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and nitrogen adsorption/desorption. The formation mechanism of mesoporous Cu 2 O–CeO 2 nanospheres was discussed. The results show that the molar ratios of Ce 3+ /Cu 2+ and the reaction time have an important influence on the nanostructure of Cu 2 O–CeO 2 composite spheres. The resultant Cu 2 O–CeO 2 nanospheres exhibit superior catalytic activities in the reduction of 4-nitrophenol to 4-aminophenol by NaBH 4 . The activity factor (K =  k /m) for the Cu 2 O–CeO 2 nanospheres prepared with the molar ratio of Ce 3+ /Cu 2+ of 5/1 is 3006.6 s −1  g −1 , which is much higher than reported values. This paper demonstrates a highly controllable approach to the production of mesoporous Cu 2 O–CeO 2 nanospheres, which have potential applications in the areas of catalysis, adsorption, sensors and so on. [ABSTRACT FROM AUTHOR]

Abnormal expressions of uracil-DNA glycosylase (UDG) have been associated with various diseases. We proposed a novel electrochemical biosensing platform-based strategy for UDG detection. This method combined NiCoP@PtCu nanozyme with multi-MNAzyme junctions. The U base was deleted in the presence of UDG, resulting in self-assembly of multi-MNAzyme junctions with the ability to continually cleave DNA hairpins and release various products. The products could bind the protective probes, exposing capture probes on the electrode's surface. Moreover, the exposed probes hybridized with the sDNAs-labeled NiCoP@PtCu nanozyme, yielding a significant electrochemical signal. The established biosensor was enzyme-free and with an ultrahigh sensitivity. Benefiting from the twofold amplification of multi-MNAzyme junctions and nanozyme, the sensing technique exhibited a large dynamic range, from 0.001 to 1.0 U mL −1 and a low detection of 6.6 × 10−4 U mL −1. In addition, the method was effectively used for UDG detection in lysed cells. Therefore, the biosensor we established has broad prospects in clinical diagnosis and biomedical research. • An enzyme-free electrochemical biosensor is developed for sensitive detection of uracil-DNA glycosylase (UDG). • multi-MNAzyme junctions possessed improved shearing efficiency and signal amplification ability. • NiCoP@PtCu nanozyme had large surface area, more active sites, well electrical conductivity, and excellent catalytic activity. • This biosensor shows low limit of detection and wide linear range of UDG activity. [ABSTRACT FROM AUTHOR]

Anatase TiO 2 nanosheets (NSs) with high surface area have been prepared via a one-step thermal decomposition of titanium tetraisopropoxide (TTIP) in oleylamine (OM), and their adsorption capacities and photocatalytic activities are investigated by using methylene blue (MB) and methyl orange (MO) as model pollutants. During the synthesis procedure, only one type of surfactant, oleylamine (OM), is used as capping agents and no other solvents are added. Structure and properties of the TiO 2 NSs were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), N 2 adsorption analysis, UV–vis spectrum, X-ray photoelectron spectroscopy (XPS) and Photoluminescence (PL) methods. The results indicate that the TiO 2 NSs possess high surface area up to 378 m 2 g − 1 . The concentration of capping agents is found to be a key factor controlling the morphology and crystalline structure of the product. Adsorption and photodegradation experiments reveal that the prepared TiO 2 NSs possess high adsorption capacities of model pollutants MB and high photocatalytic activity, showing that TiO 2 NSs can be used as efficient pollutant adsorbents and photocatalytic degradation catalysts of MB in wastewater treatment. [ABSTRACT FROM AUTHOR]

In order to improve the visible light catalytic activity of TiO 2 , the TiO 2 @g-C 3 N 4 (TCN) composite catalysts with three-dimensional porous structure and rich active sites were prepared by hydrothermal method and calcination method orderly. The synthesized TCN composites microstructures were thoroughly characterized and their performance for the photocatalytic degradation of organic dyes was investigated. The results show that the prepared composites formed the heterojunctions with a core-shell structure, which can effectively broaden the absorption spectrum of TiO 2 to visible light region. In the degradation experiments, the TCN composites exhibited excellent photocatalytic degradation effect on organic dyes, which can reach 99.65% under visible light irradiation for 2 h. The strong acid condition was benefit to the catalytic process. After five cycles of testing, the degradation efficiency of organic dyes can still maintain at 95.62% level, which indicate that the TCN composites had excellent visible light catalytic activity and reusability. [Display omitted] • The TiO 2 with three-dimensional porous structure and rich active sites were prepared by hydrothermal method. • The melamine can penetrate into the interior of TiO 2 microsphere to form TCN heterojunctions with core-shell structure. • The TCN composites with core-shell structure heterojunctions can degrade organic dyes efficiently. • The TCN composites have good stability and repeatability. [ABSTRACT FROM AUTHOR]

Fe3O4/P(GMA-DVB)/PAMAM/Au microspheres are fabricated to research the catalytic performances to 4-nitrophenol. In the preparation process, Fe3O4 microspheres act as magnetic cores, PAMAM dendrimers growing up on the surface of P(GMA-DVB) polymer work as carriers, and Au nanoparticles serve as catalytic materials. The stability of the prepared microspheres is evaluated by successively catalytic experiments to measure the conversion of 4-nitrophenol, and catalytic efficiency can still maintain up to 78.7% after ten cycles. Moreover, the effects of major factors including the concentration of the prepared microspheres and the temperature of reaction system on the conversion of 4-nitrophenol are also investigated in detail. The manuscript reveals that 4-nitrophenol can be almost converted to 4-aminophenol within 7 min at 45 °C in the case of using 1.0 g/L Fe3O4/P(GMA-DVB)/PAMAM/Au microspheres. Such excellent catalytic properties are ascribed to the optimum structure of the prepared microspheres, which favors the sufficient contact between Au nanoparticles and 4-nitrophenol. The results and strategies exhibited here provide insight into the preparation of sophisticated structures of catalysts to treat wastewater. [ABSTRACT FROM AUTHOR]

Hydrogen‐bonded organic frameworks (HOFs) are porous materials with great potential for biological applications. The self‐assembly of HOFs and biomacromolecules, however, is challenging. We report herein the self‐assembly of nanoscale HOFs (nHOFs) to encapsulate protein for intracellular biocatalysis. The self‐assembly of tetrakis(4‐amidiniumphenyl)methane and azobenzenedicarboxylate can encapsulate protein in situ to form protein@nHOFs under mild conditions. This strategy is applicable to proteins with different surface charge and molecular weight, showing a high protein encapsulation efficiency and minimal effect on protein activity. A cellular delivery study shows that the protein@TA‐HOFs can efficiently enter cells and retain enzyme activity for biochemical catalysis in living cells for neuroprotection. Our strategy paves new avenues for interfacing nHOFs with biological settings and sheds light on expanding nHOFs as a platform for biomacromolecule delivery and disease treatment. [ABSTRACT FROM AUTHOR]

Hydrogen‐bonded organic frameworks (HOFs) are porous materials with great potential for biological applications. The self‐assembly of HOFs and biomacromolecules, however, is challenging. We report herein the self‐assembly of nanoscale HOFs (nHOFs) to encapsulate protein for intracellular biocatalysis. The self‐assembly of tetrakis(4‐amidiniumphenyl)methane and azobenzenedicarboxylate can encapsulate protein in situ to form protein@nHOFs under mild conditions. This strategy is applicable to proteins with different surface charge and molecular weight, showing a high protein encapsulation efficiency and minimal effect on protein activity. A cellular delivery study shows that the protein@TA‐HOFs can efficiently enter cells and retain enzyme activity for biochemical catalysis in living cells for neuroprotection. Our strategy paves new avenues for interfacing nHOFs with biological settings and sheds light on expanding nHOFs as a platform for biomacromolecule delivery and disease treatment. [ABSTRACT FROM AUTHOR]

A simple approach towards the fabrication of Au-CeO 2 Janus-like nanoparticles is presented. Composite micelles of polystyrene- block -poly (ethylene oxide) (PS- b -PEO)/Ce(NO 3 ) 3 /HAuCl 4 with HAuCl 4 and Ce(NO 3 ) 3 precursors incorporated in the PEO domains are prepared first. By manipulating the pH value of the composite micelles solution, a redox reaction between Au(III) with Ce(III) in the PEO domains occurs and Au-CeO 2 Janus-like nanoparticles composed of a porous CeO 2 and an Au nanoparticle are generated. X-ray diffraction (XRD), UV–vis spectrum (UV), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) measurements are employed to characterize the Janus-like nanoparticles. The catalytic degradation of methyl orange dye (MO) under ultrasonic irradiation is chosen as the test reaction to examine the catalytic activity of the Au-CeO 2 Janus-like nanoparticles. It is found that Au-CeO 2 Janus-like nanoparticles show higher activity than that of CeO 2 nanoparticles or Au-CeO 2 composite nanoparticles. The increased catalytic activity of Au-CeO 2 Janus-like nanoparticles is attributed to the exposed Au core on one side of the Janus nanoparticles and the Au-CeO 2 heterointerfaces. [ABSTRACT FROM AUTHOR]

[Display omitted] • (NiFe)OOH-S catalytic layer in situ grows on the NiFe foam by combining surface reconstruction and electrochemical oxidation. • (NiFe)OOH-S shows competitive alkaline catalytic OER performance (238 mV @ 10 mA cm−2). • The S doping results in the super hydrophilic surface (CA≈0o) and optimizes the OER intermediates, improving the OER activity. • A water electrolyzer driven by solar energy is operated at industrial conditions. The well-known NiFe hydroxides show tremendous promise as low-cost oxygen evolution reaction (OER) catalysts, which however suffer from the rapid decline of activity at current densities exceeding 100 mAcm−2. Herein, we constructed a sulfur-doped OER electrode ((Ni 7 Fe 3)OOH-S) by facile sulfurization and anodic displacement processes. The as-prepared (Ni 7 Fe 3)OOH-S electrode shows an overpotential of 238 mV at 10 mA cm−2 in 1 M KOH at 25 °C, which is due to the high intrinsic catalytic activity, the super hydrophilic nature of the electrode for the S dopant. DFT calculations reveal that the S dopant changes the electronic structure and charge density (NiFe)OOH, thereby optimizing the OER rate-determining step, improving the binding energy for OER intermediates, which ensures the high intrinsic catalytic activity. In addition, the long-term stability (e.g., 200 h) at industrial-level current density (399 mV at 500 mA cm−2) holds the promise for the real application of the (Ni 7 Fe 3)OOH-S electrode. Furthermore, a solar-powered electrolyzer consisting of the (Ni 7 Fe 3)OOH-S anode and a 20 % Pt/C@CC cathode operates successfully at a low voltage of 1.46 V(10 mA cm−2) in 10 M KOH at 75 °C. Overall, the combined sulfidation and anodic displacement approach could be a general approach to prepare efficient and durable catalysts for water electrolyzers. [ABSTRACT FROM AUTHOR]

In this paper, a simple route for palladium (Pd) nanoparticles attached to the surface of hollow magnetic Fe3O4/P (GMA‐DVB)‐polyethyleneimine (PEI) microspheres was established. Due to the large amount of imidogen groups and tertiary amine groups presenting in the PEI, Pd2+ ions could be anchored to the support by complexation with a polyfunctional organic ligand. Thereafter, a magnetic Pd catalyst having a high loading amount and good dispersibility was obtained by reducing Pd2+ ions. Afterwards, the prepared catalyst was characterized by TEM, SEM, FTIR, XRD, TGA, VSM, and UV–vis in detail. Ultimately, their catalytic activity was evaluated using the reduction of 4‐nitrophenol (4‐NP). Research showed that the Fe3O4/P (GMA‐DVB)‐PEI/Pd catalyst possessed high catalytic performances for the reduction of 4‐NP with a conversion rate of 98.43% within 540 s. Furthermore, the catalyst could be easily recovered and reused at least for nine successive cycles. [ABSTRACT FROM AUTHOR]