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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]

Preferential oxidation of CO in H2 (PROX) reaction is a promising solution to the on‐board purification of CO‐contaminated H2 fuel for use in next‐generation proton‐exchange membrane fuel cells (PEMFC). However, achieving high CO selectivity, activity and structural stability across the wide temperature window remains a great challenge. Herein, we fabricate centimeter scale interfacial PROX catalysts grown from nanoporous single‐crystalline Pr2O3 and Nd2O3 monoliths with lattice surface‐deposited Pt clusters at nanoscale. We demonstrate complete and selective removal of CO in H2 over an unprecedented wide temperature window (253–403 K). The monoliths are integrated with an operational PEMFC to purify the H2 fuel contaminated with CO (30 ppm) and enable stable power output for >400 h; over two thousand times longer than without. This work demonstrates that the nanoporous single‐crystalline oxide monoliths can simultaneously achieve the stability and overall performance required to realize practically useful PEMFCs. [ABSTRACT FROM AUTHOR]

In this study, we propose a versatile method for synthesizing uniform three‐dimensional (3D) metal carbides, nitrides, and carbonitrides (MXenes)/metal–organic frameworks (MOFs) composites (Ti3C2TX/Cu‐BTC, Ti3C2TX/Fe,Co‐PBA, Ti3C2TX/ZIF‐8, and Ti3C2TX/ZIF‐67) that combine the advantages of MOFs and MXenes to enhance stability and improve conductivity. Subsequently, 3D hollow Ti3C2TX/ZIF‐67/CoV2O6 composites with excellent electron‐ and ion‐transport properties derived from Ti3C2TX/ZIF‐67 were synthesized. The specific capacitance of the Ti3C2TX/ZIF‐67/CoV2O6 electrode was 285.5 F g−1, which is much higher than that of the ZIF‐67 and Ti3C2TX/ZIF‐67 electrode. This study opens a new avenue for the design and synthesis of MXene/MOF composites and complex hollow structures with tailorable structures and compositions for various applications. [ABSTRACT FROM AUTHOR]

This work reports that a low‐temperature thermal calcination strategy was adopted to modulate the electronic structure and attain an abundance of surface‐active sites while maintaining the crystal morphology. All the experiments demonstrate that the new photocatalyst nano MIL‐125(Ti)‐250 obtained by thermal calcination strategy has abundant Ti3+ induced by oxygen vacancies and high specific surface area. This facilitates the adsorption and activation of N2 molecules on the active sites in the photocatalytic nitrogen fixation. The photocatalytic NH3 yield over MIL‐125(Ti)‐250 is enhanced to 156.9 μmol g−1 h−1, over twice higher than that of the parent MIL‐125(Ti) (76.2 μmol g−1 h−1). Combined with density function theory (DFT), it shows that the N2 adsorption pattern on the active sites tends to be from "end‐on" to "side‐on" mode, which is thermodynamically favourable. Moreover, the electrochemical tests demonstrate that the high atomic ratio of Ti3+/Ti4+ can enhance carrier separation, which also promotes the efficiency of photocatalytic N2 fixation. This work may offer new insights into the design of innovative photocatalysts for various chemical reduction reactions. [ABSTRACT FROM AUTHOR]

The delivery of protein into mammalian cells enables the dissection and manipulation of biological processes; however, this potency is challenged by the lack of an efficient protein delivery tool and a means to monitor its intracellular trafficking. Herein, we report that the hierarchical self‐assembly of tetraphenylethylene (TPE)‐featured metal–organic cages (MOCs) and β‐cyclodextrin‐conjugated polyethylenimine can generate fluorescent supramolecular nanoparticles (FSNPs) to deliver protein into neural cells, a cell line that is hard to transfect using conventional strategy. Further, the aggregation‐induced emission (AIE) of TPE enabled the fluorescent monitoring of cytosolic protein release. It is found that FSNPs can deliver and release protein into cytosol for subcellular targeting as fast as 18 h post‐delivery. Moreover, the delivery of molecular chaperone DJ‐1 using FSNPs activates MAPK/ERK signaling of neural cells to protect cells from oxidative stress. [ABSTRACT FROM AUTHOR]

MXenes have attracted great interests as supercapacitors due to their metallic conductivity, high density, and hydrophilic nature. Herein we report Ti3C2‐Cu/Co hybrids via molten salt etching in which the existence of metal atoms and their interactions with MXene via surficial O atoms were elucidated by XAFS for the first time. The electrochemical investigation of Ti3C2‐Cu electrode demonstrated the pseudocapacitive contribution of Cu and a splendid specific capacitance of 885.0 F g−1 at 0.5 A g−1 in 1.0 M H2SO4. Symmetric supercapacitor Ti3C2‐Cu//Ti3C2‐Cu was demonstrated with operating voltage of 1.6 V, areal capacitance of 290.5 mF cm−2 at 1 mA cm−2, and stability over 10 000 cycles. It delivered an areal energy density of 103.3 μWh cm−2 at power density of 0.8 mW cm−2, based on which a supercapacitor pouch was fabricated. It provides deeper insights into the molten salt mechanism and strategies for designing MXene‐based materials for electrochemical energy storage. [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]

Highlights from the article: Keywords: Aza-Achmatowicz-Umlagerung; Furan; Indol; Naturstoffsynthesen; Selektive Oxidation In Schema 1 und Tabelle 3 dieser Zuschrift sind die Stereozentren C3 und C5 von Alstofolinin A und B 6 g b invers gezeichnet, die korrekte Fassung ist hier gezeigt. Aza-Achmatowicz-Umlagerung, Furan, Indol, Naturstoffsynthesen, Selektive Oxidation.