Thermally stable organic diradicals with a triplet ground state along with large singlet‐triplet energy gap have significant potential for advanced technological applications. A series of phenylene‐bridged diradicals with oxoverdazyl and nitronyl nitroxide units were synthesized via a palladium‐catalyzed cross‐coupling reaction of the corresponding iodoverdazyls with a nitronyl nitroxide‐2‐ide gold(I) complex with high yields (up to 82%). The synthesized diradicals exhibit high stability and do...
Mon Jul 27, 2020 22:54
Production of renewable, high‐value N‐containing chemicals from lignocellulose will expand product diversity and increase the economic competitiveness of biorefinery. Herein, we report a single‐step conversion of furfural to pyrrole in 75% yield as a key N‐containing building block, achieved via tandem decarbonylation‐amination reactions over tailor‐designed Pd@S‐1 and H‐beta zeolite catalytic system. Pyrrole was further transformed into DL‐proline in two steps following carboxylation with CO 2...
Mon Jul 27, 2020 21:54
Access to clean drinking water is a recognized societal need that touches on the health and livelihood of millions of people worldwide. This is providing an incentive to develop new water‐treatment technologies. Traditional technologies, while widespread, are usually inefficient at removing organic pollutants from sewage or so‐called grey water. Macrocycle‐containing covalent polymer networks have begun to attract attention in the context of water treatment owing to the inherent stability provided...
Mon Jul 27, 2020 21:27
We study how visible light influences the activity of an electrocatalyst composed of Au and Pt nanoparticles. The bimetallic composition imparts a dual functionality: the Pt component catalyses the electrochemical oxidation of ammonia to liberate hydrogen and the Au component absorbs visible light by the excitation of localized surface plasmon resonances. Under visible‐light excitation, this catalyst exhibits enhanced electrochemical ammonia oxidation kinetics, outperforming previously reported electrochemical...
Mon Jul 27, 2020 20:55
Shaping amphiphile assemblies into a novel class of tubular architectures has been realized by programming an unconventional amphiphilic molecule with directional Watson–Crick hydrogen‐bonding interactions that are shielded from the aqueous environment. These self‐assembled nanotubes have chiral lipophilic pores about 2 nm in diameter that are able to encapsulate molecules that are complementary in size and chemical affinity. Abstract Despite the central importance of aqueous amphiphile...
Mon Jul 27, 2020 20:30
Polar functionalized isotactic and syndiotactic polypropylenes (PPs) are synthesized by direct, masking reagent‐free propylene + amino‐olefin (AO, CH 2 =CH(CH 2 ) x N n Pr 2 , x = 2, 3, 6) copolymerizations using the activated precatalysts rac ‐[Me 2 Si(indenyl) 2 ]ZrMe 2 and [Me 2 C(Cp)(fluorenyl)]ZrMe 2 , respectively. Polymerization activities at 25 °C are as high as 4208 and 535 kg/(mol·h·atm) with AO incorporation up to 4.0 mol% and 1.6 mol%, respectively. Remarkably, introducing...
Mon Jul 27, 2020 19:25
Both experimental and theoretical investigations have revealed that the chemical and physical properties of graphene are crucially determined by their topological structures. Therefore, the atomically precise synthesis of graphene nanostructures is essential for studying their fundamental physiochemical properties as well as their introduction in promising applications. Among the large family of graphene nanostructures, those containing rich or fully zigzag‐edged structures exhibit unique electronic,...
Mon Jul 27, 2020 18:28
Porous metal complexes enable single‐crystal X‐ray observation of included guests or reaction intermediates by simple soaking of the guests/substrates. Previous studies on such a technique often have difficulties in observation of chiral structures because host frameworks had no chirality. Here, we synthesized a new metal–peptide porous complex via the folding‐and‐assembly strategy and utilized the chiral pore for trapping chiral guests. Chiral alcohols and ketones were successfully included within...
Mon Jul 27, 2020 18:07
Unit‐cell‐thin zeolitic nanosheets have emerged as fascinating materials for catalysis and separation. The controllability of nanosheets stacking is extremely challenging in the chemistry of two‐dimensional zeolitic materials. So far, the organization of zeolitic nanosheets in hydrothermal synthesis has been limited by the lack of tunable control over the guest‐host interactions between organic structure‐directing agents (OSDAs) and zeolitic nanosheets. Here, we report a direct synthetic methodology...
Mon Jul 27, 2020 18:05
Single‐atom catalysts (SACs) have emerged as promising materials in heterogeneous catalysis. Previous studies reported controversial results about the relative level in activity for SACs and nanoparticles (NPs). These works have focused on the effect of metal atom arrangement, without considering the oxidation state of SACs. Here, we immobilized Pt single‐atoms on defective ceria, and controlled the oxidation state of Pt SACs, from highly oxidized (Pt0: 16.6 at%) to highly metallic state (Pt0: 83.8...
Mon Jul 27, 2020 18:05
The STW‐type zeolite is significantly attractive for developing novel enantioselective syntheses/separation of chiral compounds because it is the only chiral zeolitic microporous material whose enantioenriched synthesis has been achieved. Besides the conventional industries where zeolites are used, STW should have diverse industrial applications such as in the pharmaceutical and food industries. However, the toxic and caustic fluoride required for synthesizing STW severely hinders its commercialization...
Mon Jul 27, 2020 18:03
The performances of reported electron transport layer (ETL)‐free perovskite solar cells (PSCs) are still inferior to ETL‐containing devices. This is mainly due to severe interfacial charge recombination occurred at the transparent conducting oxide (TCO)/perovskite interface, where the photo‐injected electrons in the TCO can travel back to recombine with holes in the perovskite layer. Herein, we for the first time demonstrate that a non‐annealed, insulating, amorphous metal oxyhydroxide, atomic‐scale...
Mon Jul 27, 2020 14:55
Immunogenic cell death (ICD) is a rare immunostimulatory form of cell death which can improve clinical outcomes of chemo‐immunotherapeutic combination regimens by the establishment of a long‐term cancer immunity. None of the clinically used DNA‐binding Pt II complexes is considered a Type II ICD inducer. We generated a series of Pt II ‐carbene complexes by applying minor structural alterations to the scaffold of a Type II ICD inducer Pt‐NHC and compared their efficiencies in triggering ICD‐related...
Mon Jul 27, 2020 12:24
A new organocatalyst that has unprecedented reactivity for ring‐opening polymerization of epoxides follows a novel intramolecular ammonium cation assisted mechanism. The bifunctional catalyst incorporates two 9‐borabicyclo[3.3.1]nonane centers on the two ends as Lewis acidic sites for epoxide activation and a quaternary ammonium halide in the middle as the initiating site. Abstract This manuscript describes a kind of bifunctional organocatalyst with unprecedented reactivity for the synthesis...
Mon Jul 27, 2020 11:53
A kinetically driven ambient nitrogen reduction reaction has a Faradaic efficiency of over 44 % and an ammonia yield rate of over 161 μg mgcat −1 h−1. It employs a zeolitic imidazole framework to induce electron‐deficient sites on the catalyst and a lower d‐band to weaken catalyst–H interactions whilst promoting the catalyst–N2 interaction. Abstract The electrochemical nitrogen reduction reaction (NRR) offers a sustainable solution towards ammonia production but suffers poor reaction...
Mon Jul 27, 2020 11:52
Passing through : Highly effective photocatalysts for hydrogen evolution, driven by visible light, were developed by conferring the metal–organic framework (MOF) NH2‐MIL‐125(Ti) with active copper centers. The transient copper centers allow highly effective charge transfer, dramatically improving the carrier density, lifetime of the photogenerated charge, and photocatalytic activity. Abstract Highly effective photocatalysts for the hydrogen‐evolution reaction were developed by conferring...
Mon Jul 27, 2020 11:51
Immunotherapy is a promising strategy to treat tumors, but its low response rate and side effects are major challenges in clinical applications. This Minireview highlights a range of biomaterials with the potential to alter the tumor microenvironment to improve effectiveness and outcomes of cancer immunotherapy. Abstract Immunotherapy has made great strides in improving clinical outcomes in cancer treatment. However, few patients exhibit adequate response rates for key outcome measures...
Mon Jul 27, 2020 11:51
Ptychographic X‐ray computed tomography was used to investigate the structural make‐up of supported hydrodesulfurization catalysts. The results will allow for a better rationale of current generation catalyst performance as well as a better distribution of the active phase in next‐generation hydrodesulphurization catalysts. Abstract Hydrodesulphurization, the removal of sulphur from crude oils, is an essential catalytic process in the petroleum industry safeguarding the production of clean...
Mon Jul 27, 2020 11:51
Photoswitching in a well‐ordered self‐assembled monolayer of freestanding azobenzene derivatives was studied on the molecular scale with in situ scanning tunneling microscopy, infrared absorption spectroscopy, and ab initio calculations, revealing cooperative effects. Although the intermolecular distances prevent direct contact, trans –cis photoisomerization is enhanced by cis neighbors because the light‐induced excitation is localized. Abstract Light‐induced transitions between the...
Mon Jul 27, 2020 11:51
Switch‐hitter : A bacterial genetic switch that accepts RNAs, small molecules, and proteins as inputs was developed based on a tRNA‐mimicking structure. The switch is trans‐encoded, which makes manipulation of the target mRNA redundant. It is stable to RNase, shows a strong dynamic response, and exhibits a high level of orthogonality. Abstract Current bacterial RNA switches suffer from lack of versatile inputs and are difficult to engineer. We present versatile and modular RNA switches...
Mon Jul 27, 2020 11:50
Just a little magic : Single‐ensemble CdTeSe magic‐size clusters (MSC‐399) evolved at room temperature when binary CdTe and CdSe induction period samples were mixed and dispersed into a mixture of toluene (Tol) and octylamine (OTA). The OTA amount affects the rate of the apparent transformation from CdTe MSC‐371 into CdTeSe MSC‐399 through Steps 5/1, 3, and 6. Abstract Little is known about the pathway of room‐temperature formation of ternary CdTeSe magic‐size clusters (MSCs) obtained by...
Mon Jul 27, 2020 11:50
Delivery driver : Photo‐activated polymersome nanomotors (PNMs) composed of a biodegradable polymersome system coated with a hemisphere gold layer were utilized for intracellular delivery of molecular cargo via the assistance of a NIR laser. The active penetration of the cell membrane by the nanomotors allowed both encapsulated payloads and surrounding cargo to be delivered into cells. Abstract Synthetic nanomotors are appealing delivery vehicles for the dynamic transport of functional...
Mon Jul 27, 2020 11:50
Vacant and distorted : The microstructure of hollow multishelled structure (HoMS) perovskite oxides combined with the dual‐defects of surface oxygen vacancies and lattice distortion tuned the crystal‐field splitting energy, which promotes the thermodynamic and kinetic processes for the oxygen evolution reaction (OER). Abstract To boost the performance for various applications, a rational bottom‐up design on materials is necessary. The defect engineering on nanoparticle at the atomic level...
Mon Jul 27, 2020 11:49
“A good day at work starts with a fast read of just published papers … My favorite time of day is the morning when I discuss chemistry with my students in the labs … ” Find out more about Jin Xie in his Author Profile.
Mon Jul 27, 2020 11:23
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