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How to overcome the bottleneck of Pt–based catalysts is a research focus in the field of energy conversion, and the combination of metal oxide with Pt–based catalysts is a promising strategy to avoid platinum aggregation and introduce novel photosensitivity into traditional Pt catalysts by virtue of the photosensitivity of metal oxide semiconductors. In this work, Pt–MoOx/graphene (S) (simplified as Pt–MoOx/GN (S)) was synthesized by a solid–phase reaction with Na2MoO4 as the Mo precursor, in which Na2MoO4 was partially reduced to MoO2, leading to the formation of MoOx in the composite. The integration of MoOx with Pt results in the uniform dispersion of Pt nanoparticles. Electrochemical tests reveal that the catalytic activity of Pt–MoOx/GN (S) is comparable to that of commercial 30% PtRu/C–JM toward the oxygen reduction reaction via a 4–electron transfer process. In particular, Pt–MoOx/GN (S) displays a more positive reduction potential and stronger stability, which is ascribed to the synergies between MoOx and Pt. Owing to the introduction of photo–responsive MoOx species, Pt–MoOx/GN (S) also exhibits significantly higher mass activity under simulated sunlight illumination, which is 1.62 times as much as that without illumination. The result is in favor of converting solar energy into electric energy during a traditional electrocatalytic process.

Oxidative dehydrogenation of ethane to ethylene is an important process in light olefin industry; however, the over-oxidation of ethane leads to low ethylene selectivity. Here, we report a novel approach to electrochemical oxidative dehydrogenation of ethane in anode in conjunction with CO2 reduction at cathode in a solid oxide electrolyser using a porous single-crystalline CeO2 electrode at 600 °C. We identify and engineer the flux and chemical states of active oxygen species that evolve from the lattice at anode surface to activate and dehydrogenate ethane to ethylene via the reaction of epoxy species. Active oxygen species (O2- , O22- and O2- ) at the anode surface effectively dehydrogenate ethane to ethylene, but O- species tend to induce deep oxidation. We demonstrate exceptionally high ethylene selectivity of 95 % and an ethane conversion of 10 % with a durable operation of 300 h.

Dry reforming of CH4 /CO2 provides a promising and economically feasible route for the large-scale carbon fixation; however, the coking and sintering of catalysts remain a fundamental challenge. Here we stabilize single-crystalline Ni nanoparticles at the surface of porous single-crystalline MgO monoliths and show the quantitative production of syngas from dry reforming of CH4 /CO2 . We show the complete conversion of CH4 /CO2 even only at 700 °C with excellent performance durability after a continuous operation of 500 hours. The well-defined and catalytically active Ni-MgO interfaces facilitate the reforming reaction and enhance the coking resistance. Our findings would enable an industrially and economically viable path for carbon reclamation, and the "Nanocrystal On Porous Single-crystalline Monoliths" technique could lead to stable catalyst designs for many challenging reactions.

The non-oxidative dehydrogenation of propane to propylene plays an important role in the light-olefin chemical industry. However, the conversion and selectivity remain a fundamental challenge at low temperatures. Here we create and engineer high-density Lewis acid sites at well-defined surfaces in porous single-crystalline Mo2 N and MoN monoliths to enhance the non-oxidative dehydrogenation of propane to propylene. The top-layer Mo ions with unsaturated Mo-N1/6 and Mo-N1/3 coordination structures provide high-density Lewis acid sites at the surface, leading to the effective activation of C-H bonds without the overcracking of C-C bonds during the non-oxidative dehydrogenation of propane. We demonstrate a propane conversion of ≈11 % and a propylene selectivity of ≈95 % with porous single-crystalline Mo2 N and MoN monoliths at 500 °C.

In this study, porous vanadium-based single crystal powders are prepared by a conventional and simple method. The synthesised V6O13, VO2, V2O3 and vanadium nitride (VN) single crystal powders are porous octahedral structured materials with approximately 4 μm particle sizes. Results show that the vanadium-based porous single crystal powders effectively catalyse ethane dehydrogenation at 680 °C, and the selectivity to ethylene is over 60%. VN exhibits excellent catalytic activity for ethane dehydrogenation at 680 °C with approximately 30% conversion of ethane and about 68% selectivity to ethylene, and it exhibits good stability even after working for 48 hours. The results of this study provide important value for designing and application of other metal-based porous single-crystal materials.

Ammonia is a natural pollutant in wastewater and removal technique such as ammonia electro‐oxidation is of paramount importance. The development of highly efficient and low‐costing electrocatalysts for the ammonia oxidation reaction (AOR) and hydrogen evolution reaction (HER) associated with ammonia removal is subsequently crucial. In this study, for the first time, the authors demonstrate that a perovskite oxide LaNi0.5Cu0.5O3‐δ after being annealed in Ar (LNCO55‐Ar), is an excellent non‐noble bifunctional catalyst towards both AOR and HER, making it suitable as a symmetric ammonia electrolyser (SAE) in alkaline medium. In contrast, the LNCO55 sample fired in air (LNCO55‐Air) is inactive towards AOR and shows very poor HER activity. Through combined experimental results and theoretical calculations, it is found that the superior AOR and HER activities are attributed to the increased active sites, the introduction of oxygen vacancies, the synergistic effect of B‐site cations and the different active sites in LNCO55‐Ar. At 1.23 V, the assembled SAE demonstrates ≈100% removal efficiency in 2210 ppm ammonia solution and >70% in real landfill leachate. This work opens the door for developments towards bifunctional catalysts, and also takes a profound step towards the development of low‐costing and simple device configuration for ammonia electrolysers., A non‐noble perovskite electrocatalyst, efficiently catalyzing both AOR and HER under alkaline conditions, is identified. The assembled symmetric ammonia electrolyzer based on this bifunctional catalyst delivers the ammonia removal efficiency of ≈100% in ammonia solution and over 70% in a real landfill leachate, demonstrating the huge potential for development of low‐cost and simple configuration for ammonia electrolyzer.

Tumor-associated macrophages (TAMs) are capable of worsening hepatocellular carcinoma (HCC) prognosis by accelerating tumor growth and progression. Signaling lymphocyte activation molecule family member 6 (SLAMF6; Ly108 in mice) is an immune regulator that is involved in numerous diseases. However, whether SLAMF6 might affect macrophage function in HCC has not yet been reported. Therefore, the present study aimed to determine the relationship between SLAMF6 expression on macrophages and HCC progression. In the present study, the expression of SLAMF6 in human blood samples and mice was analyzed by flow cytometry. Furthermore, macrophage-related polarization markers were detected via reverse transcription quantitative PCR. Clonogenic formation and Transwell assay were performed to determine the proliferation, migration and invasion of HCC cells. In addition, a murine HCC model was established to detect the function of SLAMF6 in vivo. The results demonstrated that SLAMF6 expression was increased in CD14+ cells obtained from patients with HCC. It was also determined that this increase was associated with a positive hepatitis B virus DNA status and high levels of α-fetoprotein. Polarized TAMs from THP-1 cells, murine peritoneal macrophages and murine bone marrow-derived macrophages all exhibited higher levels of SLAMF6 compared with M1 cells. Furthermore, an increased expression of Ly108 was detected in macrophages obtained from mice tumor tissues, indicating that the tumor microenvironment may promote Ly108 expression and macrophage M2 polarization. Ly108 small interfering RNA was applied to macrophages, which resulted in the suppression of M2 polarization. Ly108-silenced macrophages attenuated HCC cell migration and invasion and prevented tumor growth by inhibiting the nuclear factor-κB pathway. Altogether, the results from the present study suggested that SLAMF6/Ly108 was upregulated in TAMs, which may in turn accelerate the development of HCC.

Dry reforming of CH

The Pt-Bi (Bi2O3)/GNs (PVP) composite was synthesized using aqueous solution synthesis and characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and Raman spectroscopy. It was found that the water-soluble polyvinyl pyrrolidone (PVP) helped to tune the particles’ morphology, resulting in a uniform distribution of Pt-Bi nanoclusters on the surface of graphene. Cyclic voltammetry, chronoamperometry and linear scanning voltammetry (LSV) were used to study the electrocatalytic properties towards a methanol oxidation reaction (MOR) and an oxygen reduction reaction (ORR). The results show that Pt-Bi (Bi2O3)/GNs (PVP) exhibits superior bifunctional electrocatalytic properties for both MOR and ORR, mainly due to the introduction of oxophilic Bi species and the better dispersion of the Pt-Bi nanoclusters. In particular, the electro-photo catalysis for both MOR and ORR occurred under simulated sunlight irradiation due to the existence of photo-responsive Bi species, which is helpful for converting solar energy into electric energy during a traditional electrocatalytic process.

The no-vehicle-carrying mode can effectively match the car and cargo resources, improve the efficiency of logistics operations, reduce the vacancy rate of vehicles, increase the degree of organization, and reduce the logistics costs of society and enterprises. The "Car-Free Carriage" platform is a new thing arising from the integration of modern Internet technology and traditional logistics. This article firstly analyzes the problems of car-free transportation; secondly it proposes the idea of building a car-free carrier platform; finally, it sets up a car-free carrier platform website.