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A semiconductor/environment interface has been formed in which suspended silicon nanowires (SiNWs) are in direct contact with photoactive TiO2 quantum dots. The photoactivity of TiO2 competes with the intrinsic photoresponses of p‐type silicon nanowires. Rational control of the competitive mechanism realizes remarkable mirror‐imaging photo‐switching and superior rectifying effects in a single SiNW‐based device. [ABSTRACT FROM AUTHOR]

Heterogeneous electrocatalysis closely relies on the electronic structure of the catalytic materials. The ferroelectric‐to‐paraelectric phase transition of the materials also involves a change in the state of electrons that could impact the electrocatalytic activity, but such correlation remains unexplored. Here, we demonstrate experimentally and theoretically that the intrinsic electrocatalytic activity could be regulated as exampled by hydrogen evolution reaction catalysis over two‐dimensional ferroelectric CuInP2S6. The obvious discontinuity in the overpotential and apparent activation energy values for CuInP2S6 electrode are illustrated during the ferroelectric‐to‐paraelectric phase transition caused by copper displacement around Tc point (318 K), revealing the ferroelectro‐catalytic effect on thermodynamics and kinetics of electrocatalysis. When loading Pt single atom on the CuInP2S6, the paraelectric phase one showed an improved hydrogen evolution activity with smaller apparent activation energy over the ferroelectric phase counterpart. This is attributed to the copper hopping between two sulfur planes, which alternate between strong and weak H adsorption at the Pt sites to simultaneously promote H+ reactant adsorption and H2 product desorption. [ABSTRACT FROM AUTHOR]

Large‐scale implementation of all‐solid‐state lithium batteries is impeded by the physical limitations of the interface between the electrode and solid electrolyte; specifically, high resistance and poor stability, as well as poor compatibility with Li+ migration. We report double ionic–electronic transfer interface layers grown at electrode–electrolyte interfaces by in situ polymerization of 2,2′‐bithiophene in polyethylene oxide (PEO) electrolyte. For all‐solid‐state LiFePO4∥PT‐PEO‐PT∥Li cells, the formation of a conductive polythiophene (PT) layer at the cathode–electrolyte interface resulted in an at least sevenfold decrease in interface resistance, and realized a capacity retention of about 94 % after 1000 cycles along with a lower polarization voltage under a rate of 2 C. The mixed ionic–electronic conductive layers imparted superior interface stability and contact while keeping good compatibility with the Li anode. [ABSTRACT FROM AUTHOR]

The largest Ln-Fe metal cluster [Gd12Fe14(μ3-OH)12(μ4-OH)6(μ4-O)12(TEOA)6(CH3COO)16(H2O)8]⋅(CH3COO)2(CH3CN)2⋅(H2O)20 ( 1) and the core-shell monodisperse metal cluster of 1 a@SiO2 ( 1 a=[Gd12Fe14(μ3-OH)12(μ4-OH)6(μ4-O)12(TEOA)6(CH3COO)16 (H2O)8]2+) were prepared. Experimental and theoretical studies on the magnetic properties of 1 and 1 a@SiO2 reveal that encapsulation of one cluster into one silica nanosphere not only effectively decreases intermolecular magnetic interactions but also significantly increases the zero-field splitting effect of the outer layer Fe3+ ions. [ABSTRACT FROM AUTHOR]

Probing interactions of biological systems at the molecular level is of great importance to fundamental biology, diagnosis, and drug discovery. A rational bioassay design of lithographically integrating individual point scattering sites into electrical circuits is capable of realizing real‐time, label‐free biodetection of influenza H1N1 viruses with single‐molecule sensitivity and high selectivity by using silicon nanowires as local reporters in combination with microfluidics. This nanocircuit‐based architecture is complementary to more conventional optical techniques, but has the advantages of no bleaching problems and no fluorescent labeling. These advantages offer a promising platform for exploring dynamics of stochastic processes in biological systems and gaining information from genomics to proteomics to improve accurate molecular and even point‐of‐care clinical diagnosis.A bioassay design involving lithographically integrating point scattering sites into electrical circuits is capable of realizing real‐time, label‐free biodetection of H1N1 viruses with single‐molecule sensitivity and high selectivity by using Si nanowires as local reporters in combination with microfluidics. This architecture is complementary to conventional optical techniques but has the advantages of no bleaching or fluorescent labeling. [ABSTRACT FROM AUTHOR]

Probing interactions of biological systems at the molecular level is of great importance to fundamental biology, diagnosis, and drug discovery. A rational bioassay design of lithographically integrating individual point scattering sites into electrical circuits is capable of realizing real-time, label-free biodetection of influenza H1N1 viruses with single-molecule sensitivity and high selectivity by using silicon nanowires as local reporters in combination with microfluidics. This nanocircuit-based architecture is complementary to more conventional optical techniques, but has the advantages of no bleaching problems and no fluorescent labeling. These advantages offer a promising platform for exploring dynamics of stochastic processes in biological systems and gaining information from genomics to proteomics to improve accurate molecular and even point-of-care clinical diagnosis. [ABSTRACT FROM AUTHOR]

Reversible oxygen conversion is important for various green energy technologies. Herein we synthesize a series of bimetallic coordination polymers by varying the Ni/Co ratio and using HITP (HITP=2,3,6,7,10,11‐hexaiminotriphenylene) as the ligand, to interrogate the role of metal centres in modulating the activity of the oxygen reduction reaction (ORR). Co3HITP2 and Ni3HITP2 are compared. Unpaired 3d electrons in Co3HITP2 result in less coplanarity but more radical character. Thus, despite of a reduced crystallinity and conductivity, the best ORR activity, comparable to 20 % Pt/C, is obtained for Co3HITP2, showing the 3d orbital configuration of the metal centre promotes ORR. Experimental and DFT studies show a transition of ORR pathway from four‐electron for Co3HITP2 to two‐electron for Ni3HITP2. Rechargeable zinc–air batteries using Co3HITP2 as the air cathode catalyst demonstrate excellent energy efficiency and stability. [ABSTRACT FROM AUTHOR]

A new free carbon radical was obtained in a microwave‐assisted solvothermal reaction of the primary amine (1‐methyl‐1H‐benzo[d]imidazol‐2‐yl)methanamine with FeCl3⋅6 H2O in methanol at 140 °C. Through a combination of crystallography and electrospray ionization mass spectrometry, the reaction process was studied. The longest domino reaction includes 14 steps and forms up to 12 new covalent bonds (9 C−N and 3 C−C bonds) and 3 five‐membered heterocycles. For the first time, the homolytic cleavage of a C−O bond was used to synthesize a triarylmethyl radical. A free carbon radical was obtained in a domino reaction of a primary amine with FeCl3⋅6 H2O in methanol under solvothermal conditions. In this process, which was studied by crystallography and ESI mass spectrometry, the longest domino reaction features 14 steps, and methanol is sequentially activated; in addition, the homolytic cleavage of a C−O bond is proposed. [ABSTRACT FROM AUTHOR]

To address the urgent need for clean and sustainable energy, the rapid development of hydrogen-based technologies has started to revolutionize the use of earth-abundant noble-metal-free catalysts for the hydrogen evolution reaction (HER). Like the active sites of hydrogenases, the cation sites of pyrite-type transition-metal dichalcogenides have been suggested to be active in the HER. Herein, we synthesized electrodes based on a Se-enriched NiSe2 nanosheet array and explored the relationship between the anion sites and the improved hydrogen evolution activity through theoretical and experimental studies. The free energy for atomic hydrogen adsorption is much lower on the Se sites (0.13 eV) than on the Ni sites (0.87 eV). Notably, this electrode benefits from remarkable kinetic properties, with a small overpotential of 117 mV at 10 mA cm−2, a low Tafel slope of 32 mV per decade, and excellent stability. Control experiments showed that the efficient conversion of H+ into H2 is due to the presence of an excess of selenium in the NiSe2 nanosheet surface. [ABSTRACT FROM AUTHOR]

The front cover design of the international edition of volume 53, number 20, 2014 issue of the journal "Angewandte Chemie" is presented.

Domino Reactions. In their Communication on page 3748 ff., M.‐H. Zeng et al. describe the synthesis of a free carbon radical through the domino reaction of a primary amine with FeCl3⋅6 H2O in methanol under solvothermal conditions. [ABSTRACT FROM AUTHOR]