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Liquid metal nanoparticles that are mechanically sintered at and below room temperature are introduced. This material can be sintered globally on large areas of entire deposits or locally to create liquid traces within deposits. The metallic nanoparticles are fabricated by dispersing a liquid metal in a carrier solvent via sonication. The resulting dispersion is compatible with inkjet printing, a process not applicable to the bulk liquid metal in air.

MOF-derived ZnO@ZnO Quantum Dots/C core–shell nanorod arrays grown on flexible carbon cloth are successfully fabricated as a binder-free anode for Li-ion storage. In combination with the advantages from the ZnO/C core–shell architecture and the 3D nanorod arrays, this material satisfies both efficient ion and fast electron transport, and thus shows superior rate capability and excellent cycling stability.

L. Li, J. Gong, and co-workers synthesize substoichiometric tungsten oxide single-crystal nanosheets via the exfoliation of layered tungstic acid and the subsequent introduction of oxygen vacancies in work described on page 1580. The combination of different strategies, i.e., the 2D structure, the introduction of surface oxygen vacancies, and the creation of local surface plasmonic resonance, can promote the light-harvesting performance of tungsten oxide through accumulative and synergistic effects.

An all-solution processed and all-colloidal laser is demonstrated using tailored CdSe/CdS core/shell quantum dots, which exhibit highly stable and low-threshold optical gain owing to substantially suppressed non-radiative Auger recombination.

High-quality non-stoichiometric NiO_x nanoparticles are synthesized by a facile chemical precipitation method. The NiO_x film can function as an effective hole-transport layer (HTL) without any post-treatments, while offering wide temperature applicability from room temperature to 150 °C. A high efficiency of 9.16% is achieved in organic solar cells using the NiO_x HTL. A better performance in a NiO_x-based organic light-emitting diode is observed, compared with a device using PEDOT:PSS.

2D PEG-ylated MoS₂/Bi₂S₃ composite nanosheets are successfully constructed by introducing bismuth ions to react with the two extra S atoms in a (NH₄)₂MoS₄ molecule precursor for solvo­thermal synthesis of MoS₂. The MBP nanosheets can serve as a promising platform for computed tomography and photoacoustic-imaging-guided tumor diagnosis, as well as combined tumor photothermal therapy and sensitized radiotherapy.

Substitutional heterovalent doping represents an effective method to control the optical and electronic properties of nanocrystals (NCs). Highly monodisperse II−VI NCs with deep substitutional dopants are presented. The NCs exhibit stable, dominant, and strong dopant fluorescence, and control over n- and p-type electronic impurities is achieved. Large-scale, bottom-up superlattices of the NCs will speed up their application in electronic devices.

Much attention has been paid to increase the energy density of Li-ion batteries, in order to fulfill the requirements of electric vehicles and grid-scale energy storage. While for anodes various options are available, this is not at all the case for cathodes. In this context, the inexpensive and environmentally benign iron sulfides have been investigated as cathode materials due to the remarkably high capacity based on the conversion reaction. Here, the preparation of FeS nanodots accommodated in porous graphitic carbon nanowires is reported via a combination of electrospinning technique and biomolecular-assisted hydrothermal method. These materials exhibit excellent electrochemical performances also as cathode materials, with energy densities even higher than the current LiCoO₂ intercalation cathode. Moreover, key problems of conversion reaction, such as the low degree of reversibility, large polarization are far-reachingly mitigated.

FeS nanodots accommodated in porous graphitic carbon nanowires are obtained via the combination of electrospinning technique and a biomolecular-assisted hydrothermal method. These materials exhibit excellent electrochemical performances as cathode materials. Key problems of conversion reaction, such as the low degree of reversibility and large polarization, are far-reachingly mitigated.

Silicon is one of the promising materials for solar water splitting and hydrogen production; however, it suffers from two key factors, including the large external potential required to drive water splitting reactions at its surface and its instability in the electrolyte. In this study, a successful fabrication of novel p-Si/n-SnO₂/n-Fe₂O₃ core/shell/shell nanowire (css-NW) arrays, consisting of vertical Si NW cores coated with a thin SnO₂ layer and a dense Fe₂O₃ nanocrystals (NCs) shell, and their application for significantly enhanced solar water reduction in a neutral medium is reported. The p-Si/n-SnO₂/n-Fe₂O₃ css-NW structure is characterized in detail using scanning, transmission, and scanning transmission electron microscopes. The p-Si/n-SnO₂/n-Fe₂O₃ css-NWs show considerably improved photocathodic performances, including higher photocurrent and lower photocathodic turn-on potential, compared to the bare p-Si NWs or p-Si/n-SnO₂ core/shell NWs (cs-NWs), due to increased optical absorption, enhanced charge separation, and improved gas evolution. As a result, photoactivity at 0 V versus reversible hydrogen electrode and a low onset potential in the neutral solution are achieved. Moreover, p-Si/n-SnO₂/n-Fe₂O₃ css-NWs exhibit long-term photoelectrochemical stability due to the Fe₂O₃ NCs shell well protection. These results reveal promising css-NW photoelectrodes from cost-effective materials by facile fabrication with simultaneously improved photocathodic performance and stability.

Fabrication and characterization of novel p-Si/n-SnO₂/n-Fe₂O₃ core/shell/shell nanowire arrays, consisting of Si nanowire backbones coated with a thin SnO₂ layer and a dense Fe₂O₃ nanocrystals shell, are presented. The core/shell/shell nano­wires functioning as photocathode show significantly enhanced solar water reduction in a neutral pH water than bare p-Si nanowires, and a long stability of hours without any significant morphological change.

Here, a new, fast, and versatile method for the incorporation of colloidal quantum dots (QDs) into ionic matrices enabled by liquid–liquid diffusion is demonstrated. QDs bear a huge potential for numerous applications thanks to their unique chemical and physical properties. However, stability and processability are essential for their successful use in these applications. Incorporating QDs into a tight and chemically robust ionic matrix is one possible approach to increase both their stability and processability. With the proposed liquid–liquid diffusion-assisted crystallization (LLDC), substantially accelerated ionic crystallization of the QDs is shown, reducing the crystallization time needed by one order of magnitude. This fast process allows to incorporate even the less stable colloids including initially oil-based ligand-exchanged QDs into salt matrices. Furthermore, in a modified two-step approach, the seed-mediated LLDC provides the ability to incorporate oil-based QDs directly into ionic matrices without a prior phase transfer. Finally, making use of their processability, a proof-of-concept white light emitting diode with LLDC-based mixed QD-salt films as an excellent color-conversion layer is demonstrated. These findings suggest that the LLDC offers a robust, adaptable, and rapid technique for obtaining high quality QD-salts.

The fabrication of robust and processable light emitting composites consisting of semiconductor quantum dots embedded into crystals of ionic salts is demonstrated. The quantum dots from the organic phase may be directly embedded by using the approach in this study. The method is fast and results in crystal powders directly applicable for color conversion and other applications demanding extremely photostable luminescent solids.

In article 1400497, J. H. Ngai and co-workers demonstrate that the band offset between single crystalline SrZr_xTi_1−xO₃ and Ge can be tuned through the Zr content, providing a pathway to control electrical coupling between multifunctional oxides and semiconductors.

Polyphosphate inorganic polymer is evaluated as a high-performance lubricant for steel/steel contacts at 600, 700, and 800 °C. In situ thermal tests of this lubricant indicate that liquid lubrication at the rubbing interface is occurring. Tribological testing indicates the molten polyphosphate is effective as a lubricant and, reduces friction and wear of the sliding steel/steel tribo pair substantially. The lubricated steel/steel pair shows desirable tribological performance that correlates closely with the temperature-dependent hierarchical structure of the tribo-interface under the combination of pressure, shear, and temperature. Morphological observation of worn surfaces and interfaces of steel discs is achieved using scanning electron microscopy and transmission electron microscopy (TEM). Compositional analysis and elemental distribution are performed using X-ray photoelectron spectroscopy and energy dispersive X-ray on a scanning TEM. These enable the tribochemical reactions at the rubbing surface and the formation mechanism of the hierarchical tribo-interface to be understood.

Alkali metal polyphosphate is successfully conducted as a hot metal-forming lubricant due to its excellent tribological performance on the steel/steel contact interface at elevated temperature. The hierarchical contact interface with temperature-dependent character can be achieved under tribo-stressed conditions from 600 to 800 °C. It presents opportunities to develop green and tribo-adaptive interface materials for high-temperature lubrication.

The measured energy diagram for inverted cell architectures for perovskite photovoltaic devices is presented. Band offsets are determined in direct and inverse photoemission spectroscopy. The perovskite films assume a slightly p-type characteristic on top of NiO and show good energetic alignment to adjacent organic electron transport layers. The finding explains the function of inverted devices and gives guidelines for optimization.

Semiconducting organic–inorganic nanocomposites were synthesized by an unconventional route, as described by H. Xia, Z. Lin et al. in their Communication on page 4636 ff. Using an amphiphilic poly(acrylic acid)-block-poly(3,4-ethylenedioxythiophene) (PAA-b-PEDOT) diblock copolymer as the template, monodisperse PEDOT-functionalized PbTe nanoparticles were prepared. Strong coordinative interactions between the PAA blocks and the precursor metal moieties lead to nanohybrids.

Here we propose a novel way to construct mesoporous architectures through evaporation-induced assembly of polymeric micelles with crystalline nanosheets. As a model study, we used niobate nanosheets exfoliated by the direct reaction of K₄Nb₆O₁₇⋅3 H₂O crystals with an aqueous solution of propylamine. The electrostatic interaction between negatively charged nanosheets and positively charged polymeric micelles enable us to form composite micelles with the nanosheets. Removal of the micelles by calcination results in robust mesoporous oxides with the original crystalline structure.

Mesoporous architectures were obtained through evaporation-induced assembly of polymeric micelles with crystalline nanosheets. The electrostatic interactions between negatively charged nanosheets and positively charged polymeric micelles make possible the formation of composite micelles. Removal of the micelles by calcination results in mesoporous oxides with the original crystalline structure.

Ultrathin, 2D organic layers of sub-ten nanometer thicknesses and high aspect ratios have received a great deal of attention for their graphene-like topological features and emerging properties. Rational synthetic strategies have led to the realization of periodic 2D layers with unprecedented structural precision. Herein, recent progress on the synthesis of 2D organic layers, including methods based on both non-covalent and covalent interactions, is summarized, and potential applications are highlighted. Such 2D organic nanostructures have a brilliant future as prospective multifunctional materials, showing great promise as platforms for engineering novel optoelectronic, interfacial, and bioactive properties.

Two-dimensional organic layers of mole­cular thickness and large surface area attract great interest from both synthetic chemists and materials scientists. Impressive synthetic progress has been made toward the fabrication of isolated layers with structural precision reaching the atomic level. The most recent synthetic advances are highlighted and linked to their functional perspectives.

Almost half of solar energy reaching the Earth is in the infrared, and for solar cells, IR absorbing/emitting quantum dots are highly effective photovoltaic materials. As a possible approach to generating such materials, an investigation into the incorporation of group IIB metal ions during the shelling of II–VI and III–V semiconductor core/shell quantum dots is presented. Quantum dot shells consist of ZnS and an additional metal sulphide, obtained from the decomposition of metal dithiocarbamate single-source precursors. Resultant quantum dots are characterized and interrogated using transmission electron microscopy, high-resolution transmission electron microscopy, electron diffraction, time-of-flight-secondary ion mass spectroscopy, X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy, photoluminescence emission and lifetime spectroscopy, and UV–vis spectroscopy. It is demonstrated that on incorporation of an additional metal sulphide during shelling, photoluminescence properties change dramatically according to the element and indeed, its concentration. Tunable infrared emission is achieved for Hg addition, thus a one-pot method for the synthesis of infrared emitting quantum dots from visible luminescent cores is hereby developed.

Shell formation on core/shell II–VI and III–V semicondutor nanocrystals with the triad of Group IIB metals is presented, with luminescence and effect on quantum yield investigated. Shells are formed from the decomposition of as-synthesized metal dithiocarbamates; stable, single-source precursors for metal sulphides, making this a versatile and facile method for quantum dot shelling.