On top of the volcano : The importance of the anatase crystal phase in TiO2‐IrO2 solid solutions in forming highly active Ir sites for the oxygen evolution reaction (OER), around the top of the volcano plot, is shown through theoretical and experimental studies. Such highly active Ir sites are indirectly obtained by creating Sr‐deficient surfaces on SrTiO3‐SrIrO3 solid solutions in situ. Abstract Reducing the amount of iridium in oxygen evolution electrocatalysts without compromising their...
Mon Jun 29, 2020 15:20
Functional microcapsules for stable lithium metal anodes (LMAs) have been designed based on double‐shelled C@MoS2 nanostructures preloaded with sulfur. The as‐prepared C@MoS2/S structures can provide a long‐term supply of polysulfides, which serve as an effective additive for improving the stability of the solid electrolyte interphase on the LMA, thus prolonging the cycle life. Abstract The growth of Li dendrites hinders the practical application of lithium metal anodes (LMAs). In this...
Mon Jun 29, 2020 14:42
The biotransformation of the neonicotinoid pesticide sulfoxaflor and the metabolic responses in Sprague‐Dawley rats was investigated. Sulfoxaflor transformation was catalyzed by cytochrome P450 while five phase I and four phase II metabolites were identified in vivo. Exposure to sulfoxaflor caused dysregulation of bile acid synthesis and reabsorption by the expression of farnesoid X receptor (FXR). Abstract In the present study, we investigated the biotransformation of the neonicotinoid...
Mon Jun 29, 2020 14:41
Mon Jun 29, 2020 13:24
The small print : Co‐N‐C single‐atom catalysts were derived from metal– organic frameworks and compared with related nanoparticles in the selective dehydrogenation of formic acid. The highly dispersed single CoIIN x sites demonstrated improved reactivity and resistance to acid, constituting the current state‐of‐the‐art in low‐cost earth‐abundant catalyst for this transformation. Abstract Metal–organic framework (MOF)‐derived Co‐N‐C catalysts with isolated single cobalt atoms have...
Mon Jun 29, 2020 13:19
The methanol‐to‐olefins reaction catalyzed by small‐pore cage‐based acid zeolites and zeotypes produces a mixture of short chain olefins, whose selectivity to ethene, propene and butene varies with the cavity architecture and with the framework composition. The product distribution of aluminosilicates and silicoaluminophosphates with the CHA and AEI structures (H‐SSZ‐13, H‐SAPO‐34, H‐SSZ‐39 and H‐SAPO‐18) has been experimentally determined, and the impact of acidity and framework flexibility on the...
Mon Jun 29, 2020 12:23
The synthesis of a new conjugated oligoelectrolyte (COE), namely DSAzB , is described, which contains a conjugated core bearing a diazene moiety in the center of its electronically delocalized structure. Similar to structurally‐related phenylenevinylene‐based COEs, DSAzB readily intercalates into model and natural lipid bilayer membranes. Photo‐induced isomerization transforms the linear trans COE into a bent or C‐shape form. It is thereby possible to introduce DSAzB into the bilayer of a...
Mon Jun 29, 2020 11:27
Upcycling : A sixfold trichlorosilylated butadiene dianion is accessible in one step from hexachlorobutadiene and the Si2Cl6/Cl− system. Cl− abstraction with AlCl3 causes a double cyclization reaction and quantitatively forms a six‐membered double silacyclobutene. Abstract The exhaustive trichlorosilylation of hexachloro‐1,3‐butadiene was achieved in one step by using a mixture of Si2Cl6 and [n Bu4N]Cl (7:2 equiv) as the silylation reagent. The corresponding butadiene dianion salt [n Bu4N]2[1...
Mon Jun 29, 2020 11:15
Stability : Despite the excellent optoelectronic properties of halide perovskites, their stability under ambient conditions and, more importantly, in aqueous medium are poor, thus limiting their application in solar photoelectrochemical (PEC) devices. Reported here is an extremely stable vacancy ordered halide perovskite, Cs2PtI6, which is stable for at least one year under ambient conditions and for 24 hours in extreme pH conditions. It also demonstrated 12 hours of solar PEC water oxidation,...
Mon Jun 29, 2020 11:14
Heptazine‐based C3N4 photocatalysts with heteroatom dopants exhibit potassium‐induced interlayer charge separation and local charge polarization on sulfur sites. This facilitates O2 adsorption and the subsequent two‐electron reduction of dioxygen to achieve highly efficient and selective production of H2O2 up to a millimolar level per hour and 100 % apparent quantum yield at 420 nm. Abstract Polymeric carbon nitride modified with selected heteroatom dopants was prepared and used as a model...
Mon Jun 29, 2020 11:14
Vitamin K for Al : Attempts to enhance the reactivity of a β‐diketiminate AlI complex by addition of a potassium reagent led to ligand deprotonation, yielding a different highly reactive anionic AlI complex. Addition of benzene gave two C−H bond activations exclusively in para ‐positions. Abstract The reagent RK [R=CH(SiMe3)2 or N(SiMe3)2] was expected to react with the low‐valent (DIPPBDI)Al (DIPPBDI=HC[C(Me)N(DIPP)]2, DIPP=2,6‐i Pr‐phenyl) to give [(DIPPBDI)AlR]−K+. However, deprotonation...
Mon Jun 29, 2020 11:13
Ligand‐like , polyvinylpyrrolidone molecules stabilize single‐atom Pt during UV‐induced photoreduction on titanium oxide nanorods encapsulated by graphitic carbon. The resulting material shows extremely high activity toward the hydrogen evolution reaction. Abstract The essence of developing a Pt‐based single‐atom catalyst (SAC) for hydrogen evolution reaction (HER) is the preparation of well‐defined and stable single Pt sites with desired electrocatalytic efficacy. Herein, we report a facile...
Mon Jun 29, 2020 11:13
The direct transformation of readily available phenol derivatives into valuable trifluoromethylarenes was developed. The PMe3‐catalyzed oxidative addition and transmetalation, as well as CCl3CN‐induced reductive elimination play key roles in this successful nickel‐mediated trifluoromethylation. Abstract The increasing pharmaceutical importance of trifluoromethylarenes has stimulated the development of more efficient trifluoromethylation reactions. Tremendous efforts have focused on copper‐...
Mon Jun 29, 2020 11:12
Crucial intermediate : A surface gem ‐diol‐type species is identified in the activation of acetone on the open Sn site of Sn‐β zeolite by using solid‐state NMR spectroscopy. This species promotes alcohol adsorption and provides an energy‐favorable route for hydrogen transfer in the Meerwein–Ponndorf–Verley–Oppenauer reaction. Abstract Lewis acid zeolites have found increasing application in the field of biomass conversion, in which the selective transformation of carbonyl‐containing molecules...
Mon Jun 29, 2020 11:11
Well balanced : A fullerene‐based molecular torsion balance is constructed to investigate noncovalent arene–fullerene interactions. The interactions are weak but measurable. The linear correlation between the difference in the free energies of two well‐defined conformers and the Hammett constants of the substituents on the arene moieties indicate that the electrostatic interactions are a significant contribution. Abstract To investigate the nature and strength of noncovalent interactions...
Mon Jun 29, 2020 11:10
The synthesis of artificial mussel‐glue proteins with pH triggered cohesion control mechanism is described by extending the tyrosinase activated polymerization of peptides to sequences having specific modules for cohesion control. The high propensity of those sequence sections to adapt β‐sheets is temporarily suppressed by switch defects. This allows enzymatic activation and polymerization to proceed undisturbed. The β‐sheet formation is regained after polymerization by changing pH from 5.5 to 6.8,...
Sun Jun 28, 2020 22:00
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