The fact that the lifetime of photoluminescence often is difficult to access because of the weakness of the emission signals, seriously limits the possibility to gain local bioimaging information in time‐resolved luminescence probing. We herein aim to provide a solution to this problem by creating a general photophysical strategy based on the use of molecular probes designed for single‐luminophore dual thermally activated delayed fluorescence (TADF). The structural and conformational design makes...
Thu Jul 23, 2020 18:13
Selectivity control is one of the central topics in organic chemistry. Although the alkoxyl radical induced unprecedented transformations have drawn more attentions, compared to the booming selective C‐H activation, the selective radical O‐H activation remains less explored. Herein, we report a novel selective radical O‐H activation strategy of diols by combining spatial effect with proton coupled electron transfer (PCET). The common molecule DMSO is found to be an essential reagent that enables...
Thu Jul 23, 2020 17:43
The catalytic oxidation of carbon monoxide (CO) on transition metals, such as platinum (Pt), is commonly viewed as a sharp transition from the CO‐inhibited surface to the active metal, covered with oxygen (O). However, we find that minor amounts of O are present in the CO‐poisoned layer that explain why, surprisingly, CO desorbs at stepped and flat Pt crystal planes at once, regardless of the reaction conditions. Using near‐ambient pressure X‐ray photoemission and a curved Pt(111) crystal we probe...
Thu Jul 23, 2020 16:17
Theoretical studies predicted the planar cyclopenten‐4‐yl cation to be a classical carbocation, and the highest‐energy isomer of C5H7+. Hence, its existence has not been verified experimentally so far. We were now able to isolate two stable derivatives of the cyclopenten‐4‐yl cation by reaction of bulky alanes CpRAlBr2 with AlBr3. Elucidation of their (electronic) structures by X ray diffraction and quantum chemistry studies revealed planar geometries and strong hyperconjugation interactions primarily...
Thu Jul 23, 2020 16:15
Di‐2,7‐naphthihexaphyrin(1.1.1.1.1.1), a non‐aromatic carba‐analogue of the hexaphyrin(1.1.1.1.1.1), incorporating two built‐in 2,7‐naphthylene moieties was synthesized as two separate, conformationally locked stereoisomers. Both conformers followed complex protonation pathways involving structurally different species, which can be targeted under kinetic and thermodynamic control. The neutralization of the ultimate dicationic product, accessible from both stereoisomers of the free base, allowed to...
Thu Jul 23, 2020 13:13
Despite the great potential of radical chemistry in organic synthesis, N‐heterocyclic carbene (NHC)‐catalyzed reactions involving radical intermediates are not well explored. This communication reports the three‐component coupling of aroyl fluorides, styrenes and the Langlois reagent (CF 3 SO 2 Na) to give various β‐trifluoromethylated alkyl aryl ketones with good functional group tolerance in moderate to high yields by cooperative photoredox/NHC catalysis. The alkene acyltrifluoromethylation...
Thu Jul 23, 2020 12:08
A versatile grafting–filtering strategy was developed to controllably modify commercial polyolefin separators for sodium batteries. The as‐developed Janus separators contain a sodium‐ion‐conducting polymer‐grafted side and a functional low‐dimensional material coated side. The separator demonstrates high capacity and extended cycling life with lean electrolyte loading in sodium batteries. Abstract Rechargeable sodium batteries are a promising technology for low‐cost energy storage. However,...
Thu Jul 23, 2020 22:00
H 2 O 2 is a versatile and environmentally friendly chemical involved in water treatment, such as advanced oxidation processes. Anthraquinone oxidation is widely used for large‐scale production of H 2 O 2 , which requires significant energy input and periodic replacement of the carrier molecule. H 2 O 2 production method should be customized considering the specific usage scenario. Electrochemical synthesis of H 2 O 2 can be adopted as alternatives to traditional method, which avoids...
Thu Jul 23, 2020 11:39
Colorful to the core : Rotaxane formation was used to lock a cyanine dye along the axis of a porphyrin nanoring to form a complex that mimics the photophysical behavior of the light‐harvesting complex LH1 and the reaction center in purple photosynthetic bacteria. Energy is transferred rapidly between the axial dye and the surrounding nanoring. Abstract A nanoring‐rotaxane supramolecular assembly with a Cy7 cyanine dye (hexamethylindotricarbocyanine) threaded along the axis of the nanoring...
Thu Jul 23, 2020 11:06
Tillandsia species with degenerated roots have evolved into hygroscopic leaves that absorb moisture from air, transport water molecules from the leaves surface to internal network via osmotic pressure and further hold them for sustainable growing requirements. This interesting biological adaptability has inspired us to develop an integrated hygroscopic photothermal organogel (POG) to achieve a solar‐powered atmospheric water harvesting (AWH). The well‐designed hydrophilic co‐polymeric skeleton is...
Wed Jul 22, 2020 18:15
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