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Angewandte Chemie, Wiley, Vol. 134, No. 15 ( 2022-04-04)

Mn‐doping in cesium lead halide perovskite nanoplatelets (NPls) is of particular importance where strong quantum confinement plays a significant role towards the exciton–dopant coupling. In this work, we report an immiscible bi‐phasic strategy for post‐synthetic Mn‐doping of CsPbX 3 (X=Br, Cl) NPls. A systematic study shows that electron‐donating oleylamine acts as a shuttle ligand to transport MnX 2 through the water–hexane interface and deliver it to the NPls. The halide anion also plays an essential role in maintaining an appropriate radius of Mn 2+ and thus fulfilling the octahedral factor required for the formation of perovskite crystals. By varying the thickness of parent NPls, we can tune the dopant incorporation and, consequently, the exciton‐to‐dopant energy transfer process in doped NPls. Time‐resolved optical measurements offer a detailed insight into the exciton‐to‐dopant energy transfer process. This new approach for post‐synthetic cation doping paves a way towards exploring the cation exchange process in several other halide perovskites at the polar–nonpolar interface.

Online Resource

0044-8249, 1521-3757

English

Wiley

2022

505868-5

506609-8

514305-6

505872-7

1479266-7

505867-3

506259-7

Angewandte Chemie, Wiley, Vol. 134, No. 10 ( 2022-03)

Chiral hybrid organic–inorganic metal halides (HOMHs) with intrinsic noncentrosymmetry have shown great promise for applications in second‐order nonlinear optics (NLO). However, established chiral HOMHs often suffer from their relatively small band gaps, which lead to negative impacts on transparent window and laser‐induced damage thresholds (LDT). Here, we have synthesized two chiral HOMHs based on Cu I halides, namely ( R ‐ /S ‐MBA)CuBr 2 , which feature well‐balanced NLO performances with a highly efficient SHG response, outstanding optical transparency, and high LDT. The effective second‐order NLO coefficient of ( R ‐MBA)CuBr 2 has been determined to be ≈24.7 pm V −1 , which is two orders of magnitude higher than that of their Cu II counterparts. This work shows the promising potential of Cu I ‐based chiral HOMHs for nonlinear photonic applications in wide wavelength regions.

Online Resource

0044-8249, 1521-3757

English

Wiley

2022

505868-5

506609-8

514305-6

505872-7

1479266-7

505867-3

506259-7

physica status solidi (b), Wiley, Vol. 34, No. 2 ( 1969-01)

Online Resource

0370-1972, 1521-3951

English

Wiley

1969

208851-4

1481096-7

Angewandte Chemie, Wiley, Vol. 134, No. 12 ( 2022-03-14)

Constructing monodispersed metal sites in heterocatalysis is an efficient strategy to boost their catalytic performance. Herein, a new strategy using monodispersed metal sites to tailor Pt‐based nanocatalysts is addressed by engineering unconventional p–d orbital hybridization. Thus, monodispersed Ga on Pt 3 Mn nanocrystals (Ga‐O‐Pt 3 Mn) with high‐indexed facets was constructed for the first time to drive ethanol electrooxidation reaction (EOR). Strikingly, the Ga‐O‐Pt 3 Mn nanocatalyst shows an enhanced EOR performance with achieving 8.41 times of specific activity than that of Pt/C. The electrochemical in situ Fourier transform infrared spectroscopy results and theoretical calculations disclose that the Ga‐O‐Pt 3 Mn nanocatalyst featuring an unconventional p–d orbital hybridization not only promote the C−C bond‐breaking and rapid oxidation of ‐OH of ethanol, but also inhibit the generation of poisonous CO intermediate species. This work discloses a promising strategy to construct a novel nanocatalysts tailored by monodispersed metal site as efficient fuel cell catalysts.

Online Resource

0044-8249, 1521-3757

English

Wiley

2022

505868-5

506609-8

514305-6

505872-7

1479266-7

505867-3

506259-7

physica status solidi (b), Wiley, Vol. 34, No. 1 ( 1969-01)

Online Resource

0370-1972, 1521-3951

English

Wiley

1969

208851-4

1481096-7

physica status solidi (b), Wiley, Vol. 34, No. 1 ( 1969-01)

Online Resource

0370-1972, 1521-3951

English

Wiley

1969

208851-4

1481096-7

physica status solidi (b), Wiley, Vol. 34, No. 1 ( 1969-01)

Online Resource

0370-1972, 1521-3951

English

Wiley

1969

208851-4

1481096-7

physica status solidi (b), Wiley, Vol. 34, No. 1 ( 1969-01)

Online Resource

0370-1972, 1521-3951

English

Wiley

1969

208851-4

1481096-7

physica status solidi (b), Wiley, Vol. 34, No. 1 ( 1969-01)

Online Resource

0370-1972, 1521-3951

English

Wiley

1969

208851-4

1481096-7

Angewandte Chemie, Wiley, Vol. 134, No. 11 ( 2022-03-07)

A reaction between two prebiotically plausible building blocks, hydantoin and glyoxylate, generates both the nucleobase orotate, a precursor of biological pyrimidines, and pyruvate, a core metabolite in the citric acid cycle and amino acid biosynthesis. The reaction proceeds in water to provide significant yields of the two widely divergent chemical motifs. Additionally, the reaction of thiohydantoin and glyoxylate produces thioorotate in high yield under neutral aqueous conditions. The use of an open‐chain thiohydantoin derivative also enables the potential pre‐positioning of a nucleosidic bond prior to the synthesis of an orotate nucleoside. The observation that diverse building blocks of modern metabolism can be produced in a single reaction pot, from common reactants under mild conditions, supports the plausibility of orthogonal chemistries operating at the origins of chemical evolution.

Online Resource

0044-8249, 1521-3757

English

Wiley

2022

505868-5

506609-8

514305-6

505872-7

1479266-7

505867-3

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Angewandte Chemie, Wiley, Vol. 134, No. 11 ( 2022-03-07)

Considering the ubiquitous nature and ready synthesis of amides, and the great significance of organofluorine‐containing species, the cross‐coupling of amides and polyfluoroarenes, leading to new carbon–carbon bond‐forming methodologies, would find useful applications in synthesis, late‐stage functionalization, and rapid generation of molecular diversity. Herein, we present a novel synthesis of α‐polyfluoroaryl amines via Sm/SmI 2 ‐mediated deoxygenative cross‐coupling of aromatic amides with polyfluoroarenes through direct C−H functionalization. The structural and functional diversity of these readily available precursors provides a versatile and flexible strategy for the streamlined synthesis of α‐polyfluoroaryl amines. Combining experimental and theoretical studies, a novel plausible mechanism of the α‐aminocarbene‐mediated C−H insertion has been revealed, which may stimulate future work for the development of novel methods in amine synthesis.

Online Resource

0044-8249, 1521-3757

English

Wiley

2022

505868-5

506609-8

514305-6

505872-7

1479266-7

505867-3

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physica status solidi (b), Wiley, Vol. 35, No. 1 ( 1969-01), p. 481-489

Die Theorie der Defektzustände wird mit einer Pseudopotentialmethode neu formuliert. Dabei wird die EMA (effective Massen‐Approximation) und TBA (Two‐Band‐Approximation) erhalten. Ein einfaches Kriterium wird gefunden, um die Fehler, die durch einige Hypothesen eingebracht werden, abzuschätzen. Eine Gleichung in der Einbandnäherung, die für tiefe und flache Zustände gültig ist, wird mit dem Störstellen‐Pseudopotential abgeleitet, jedoch mit einer effektiven Masse und der dielektrischen Funktion.

Online Resource

0370-1972, 1521-3951

English

Wiley

1969

208851-4

1481096-7

physica status solidi (b), Wiley, Vol. 33, No. 2 ( 1969-01), p. 843-850

In Aluminium wurden nach α‐Bestrahlung bei 21,4°K im Temperaturbereich von 40 bis 75 °K vier Maxima der inneren Reibung gemessen. Zwei dieser Maxima haben die natürliche Linienbreite. Dem Ausheilverhalten der Maxima zufolge – sie heilen in Stufe II mit 1. Ordnung aus – wurden die Reibungsmaxima der Umorientierung von Mehrfach‐Zwischengitteratomen zugeordnet. Die Aktivierungsenergie für Relaxation ist deutlich kleiner als für Wanderung.

Online Resource

0370-1972, 1521-3951

English

Wiley

1969

208851-4

1481096-7

Angewandte Chemie, Wiley, Vol. 134, No. 12 ( 2022-03-14)

Li–O 2 batteries have aroused considerable interest in recent years, however they are hindered by high kinetic barriers and large overvoltages at cathodes. Herein, a step‐scheme (S‐scheme) junction with hematite on carbon nitride (Fe 2 O 3 /C 3 N 4 ) is designed as a bifunctional catalyst to facilitate oxygen redox for a visible‐light‐involved Li–O 2 battery. The internal electric field and interfacial Fe−N bonding in the heterojunction boost the separation and directional migration of photo‐carriers to establish spatially isolated redox centers, at which the photoelectrons on C 3 N 4 and holes on Fe 2 O 3 remarkably accelerate the discharge and charge kinetics. These enable the Li–O 2 battery with Fe 2 O 3 /C 3 N 4 to present an elevated discharge voltage of 3.13 V under illumination, higher than the equilibrium potential 2.96 V in the dark, and a charge voltage of 3.19 V, as well as superior rate capability and cycling stability. This work will shed light on rational cathode design for metal–O 2 batteries.

Online Resource

0044-8249, 1521-3757

English

Wiley

2022

505868-5

506609-8

514305-6

505872-7

1479266-7

505867-3

506259-7

Angewandte Chemie, Wiley, Vol. 134, No. 6 ( 2022-02)

Online Resource

0044-8249, 1521-3757

English

Wiley

2022

505868-5

506609-8

514305-6

505872-7

1479266-7

505867-3

506259-7

physica status solidi (b), Wiley, Vol. 33, No. 2 ( 1969-01)

Online Resource

0370-1972, 1521-3951

English

Wiley

1969

208851-4

1481096-7

physica status solidi (b), Wiley, Vol. 33, No. 2 ( 1969-01)

Online Resource

0370-1972, 1521-3951

English

Wiley

1969

208851-4

1481096-7

physica status solidi (b), Wiley, Vol. 35, No. 1 ( 1969-01)

Online Resource

0370-1972, 1521-3951

English

Wiley

1969

208851-4

1481096-7

physica status solidi (b), Wiley, Vol. 35, No. 1 ( 1969-01)

Online Resource

0370-1972, 1521-3951

English

Wiley

1969

208851-4

1481096-7

physica status solidi (b), Wiley, Vol. 33, No. 2 ( 1969-01)

Online Resource

0370-1972, 1521-3951

English

Wiley

1969

208851-4

1481096-7