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Hydrogen boride (HB), a freestanding 2D hydrogenated‐borophene (borophane) polymorph, is synthesized via ion exchange. HB sheets with a B/H atomic ratio of 1.0 are confirmed to contain three‐center–two‐electron B–H–B bonds and two‐center–two‐electron terminal B–H bonds. The optical properties of HB sheets are expected to be tunable by changing the BHB/BH bond ratio, which alters the electronic structure of HB sheets; however, this is not yet achieved. This study demonstrates that controlling the BHB/BH bond ratio in the HB sheets is possible without altering the hydrogen content by adjusting the volume of ion‐exchange resin during synthesis, thus enabling the tuning of the photoinduced H2 release under UV irradiation. Furthermore, the fluorescence intensity correlates with the absorbance ratio of the BHB and BH vibrational modes. Increasing the BHB/BH bond ratio enhances the luminescence intensity, whereas reducing it enhances the photoinduced H2 release rate under UV irradiation. The ability to control the BHB/BH bond ratio of HB sheets provides new avenues for optimizing their properties for various applications, including hydrogen storage and photocatalysis. [ABSTRACT FROM AUTHOR]

Time‐resolved pair distribution function (PDF) analysis is performed to clarify the formation mechanism of Li3PS4 sulfide solid electrolytes in liquid phase synthesis with acetonitrile (AN), tetrahydrofuran (THF), and ethyl acetate (EA) solvents. This aims to clarify the relationship between their formations and lithium ionic conductivity. A complex is formed between the precursor of the sulfide solid electrolyte and each solvent during the liquid phase synthesis. The ratio of the solvent to the electrolyte is 3.03 in THF solution. The formation speed of precursors of sulfide solid electrolytes increases in the order AN < THF < EA solution, which is the same order as the lithium ionic conductivity. Thus, the correlation between the ionic conductivity and the formation rate of the precursor of the sulfide solid electrolyte might be related to the stability of the complex formed between Li3PS4 and the solvent during liquid phase synthesis. [ABSTRACT FROM AUTHOR]

Controlling the shape and size of nanostructured materials has been a topic of interest in the field of material science for decades. In this work, the ferroelectric material SrxBa1−xNb2O6 (x=0.32–0.82, SBN) was prepared by hydrothermal synthesis, and the morphology is controllably changed from cube‐shaped to hollow‐ended structures based on a fundamental understanding of the precursor chemistry. Synchrotron X‐ray total scattering and PDF analysis was used to reveal the structure of the Nb‐acid precursor, showing Lindqvist‐like motifs. The changing growth mechanism, from layer‐by‐layer growth forming cubes to hopper‐growth giving hollow‐ended structures, is attributed to differences in supersaturation. Transmission electron microscopy revealed an inhomogeneous composition along the length of the hollow‐ended particles, which is explained by preferential formation of the high entropy composition, SBN33, at the initial stages of particle nucleation and growth. [ABSTRACT FROM AUTHOR]

A dedicated apparatus has been developed for studying structural changes in amorphous and disordered crystalline materials substantially in real time. The apparatus, which can be set up on beamlines BL04B2 and BL08W at SPring‐8, mainly consists of a large two‐dimensional flat‐panel detector and high‐energy X‐rays, enabling total scattering measurements to be carried out for time‐resolved pair distribution function (PDF) analysis in the temperature range from room temperature to 873 K at pressures of up to 20 bar. For successful time‐resolved analysis, a newly developed program was used that can monitor and process two‐dimensional image data simultaneously with the data collection. The use of time‐resolved hardware and software is of great importance for obtaining a detailed understanding of the structural changes in disordered materials, as exemplified by the results of commissioned measurements carried out on both beamlines. Benchmark results obtained using amorphous silica and demonstration results for the observation of sulfide glass crystallization upon annealing are introduced. A new apparatus for total scattering measurements has been developed with a variable camera length using a 16‐inch two‐dimensional flat‐panel detector to observe structural changes in amorphous and disordered crystalline materials substantially in real time on beamlines BL08W and BL04B2 at SPring‐8. This paper presents the successful time‐resolved pair distribution function analysis at SPring‐8, and a newly developed program for data conversion from two‐dimensional images into one‐dimensional total scattering patterns. [ABSTRACT FROM AUTHOR]

Owing to the inexpensiveness and non‐toxicity of iron, development of highly active and simple homogeneous iron photocatalysts is a crucially important, while challenging, for practical organic synthetic reactions. Here we report that iron(III) nitrate, which is one of the most typical iron salts and can form iron aquo complexes in aqueous and organic solutions, can be used as a highly efficient and selective homogeneous photocatalyst for fine chemical synthesis. We demonstrated the iron aquo complexes catalyzed the oxidation of cyclohexane into cyclohexanol and cyclohexanone with a turnover number (TON) of 88 and a nearly 100 % selectivity using O2 under irradiation of solar light, whereas existing TiO2 and α‐Fe2O3 heterogeneous photocatalysts showed low TON and no activity. The iron aquo complexes impregnated within a mesoporous silica showed the improved TON of up to 100 while maintaining nearly 100 % selectivity. Iron for oxidation: Simple iron(III) aquo complex, [Fe(H2O)6]3+, can be used as an unprecedentedly highly effective and selective homogeneous photocatalyst for partial oxidation of cyclohexane to produce higher value products using O2 under irradiation of solar light. [ABSTRACT FROM AUTHOR]

Mesoporous cobalt phosphide (meso-CoP) was prepared by the phosphorization of ordered mesoporous cobalt oxide (meso-Co3O4). The electrical conductivity of meso-CoP is 37 times higher than that of nonporous CoP, and it displays semimetallic behavior with a negligibly small activation energy of 26 meV at temperatures below 296 K. Above this temperature, only materials with mesopores underwent a change in conductivity from semimetallic to semiconducting behavior. These properties were attributed to the coexistence of nanocrystalline Co2P phases. The poor crystallinity of mesoporous materials has often been considered to be a problem but this example clearly shows its positive aspects. The concept introduced here should thus lead to new routes for the synthesis of materials with high electronic conductivity. [ABSTRACT FROM AUTHOR]

The synthesis of a novel family of cyano-bridged trimetallic coordination polymers (CPs) with various compositions and shapes has been reported by changing the compositional ratios of Fe, Co, and Ni species in the reaction system. In order to efficiently control the nucleation rate and the crystal growth, trisodium citrate dihydrate plays an important role as a chelating agent. After the obtained cyano-bridged trimetallic CPs undergo thermal treatment in air at three different temperatures (250, 350, and 450 °C), nanoporous spinel metal oxides are successfully obtained. Interestingly, the obtained nanoporous metal oxides are composed of small crstalline grains, and the grains are oriented in the same direction, realizing pseudo-single crystals with nanopores. The resultant nanoporous spinel oxides feature interesting magnetic properties. Cyano-bridged multimetallic CPs with various sizes and shapes can provide a pathway toward functional nanoporous metal oxides that are not attainable from simple cyano-bridged CPs containing single metal ions. [ABSTRACT FROM AUTHOR]

Platinum nanoparticles with continuously tunable mesoporous structures were prepared by a simple, one-step polymeric approach. By virtue of their large pore size, these structures have a high surface area that is accessible to reagents. In the synthetic method, variation of the solvent composition plays an essential role in the systematic control of pore size and particle shape. The mesoporous Pt catalyst exhibited superior electrocatalytic activity for the methanol oxidation reaction compared to commercially available Pt catalysts. This polymeric-micelle approach provides an additional design concept for the creation of next generation of metallic catalysts. [ABSTRACT FROM AUTHOR]

Deposition of Ni-based cyanide bridged coordination polymer (NiCNNi) flakes onto the surfaces of graphene oxide (GO) sheets, which allows precise control of the resulting lamellar nanoarchitecture by in situ crystallization, is reported. GO sheets are utilized as nucleation sites that promote the optimized crystal growth of NiCNNi flakes. The NiCNNicoated GO sheets then self-assemble and are stabilized as ordered lamellar nanomaterials. Regulated thermal treatment under nitrogen results in a Ni3C-GO composite with a similar morphology to the starting material, and the Ni3C-GO composite exhibits outstanding electrocatalytic activity and excellent durability for the oxygen reduction reaction. [ABSTRACT FROM AUTHOR]

We report that a nanoporous Au film capped with a dielectric surface layer enables the effective absorption of near-infrared light and intense emission of two-photon luminescence. In this approach, nanoscale pores in Au are incorporated by chemical dissolution and microscale surface patterns are added on the nanoporous Au by microcontact print lithography. Electromagnetic simulation shows that the strong local electric fields are concentrated in the vicinity of nanopores in the Au film and are further increased by the surface dielectric patterns, which leads to a 40-fold increase in the intensity of the two-photon luminescence, as verified by photoemission measurement. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

This paper reviews important research on chemical and electrochemical synthesis and application of nanoparticles, especially our recent results in this field: (i) catalytic metal nanoparticles for micro-fuel cells, (ii) magnetic oxide nanoparticles for drug delivery systems, and (iii) magnetic metal nanoparticles for magnetic recording media. To fulfill the requirements of each application, we chose and modified those synthetic methods for obtaining suitable properties, e.g., morphology, catalytic activity, and magnetic properties. (i) For micro-fuel cells, electrodeposition is attractive because of its selective deposition onto current collectors and possible elimination of an annealing process. As a result, we have successfully synthesized Pt, PtRu alloy, and PdCo alloy, which consisted of dendritic structures macroscopically and of interconnected nanoparticles microscopically. (ii) For drug delivery systems, since magnetic nanoparticles should possess ferromagnetism, be dispersible in water, and be nontoxic, Fe3O4 nanoparticles synthesized by hydrolysis in aqueous media are suitable. As a result, we have successfully controlled the size (10-40 nm in diameter) and the magnetic properties of Fe3O4 nanoparticles by means of adjusting the molar ratio of ferrous to ferric ions in the precursor solution. (iii) For magnetic recording materials, since magnetic nanoparticles should possess high coercivity, a controlled shape, and a uniform small size, we have modified a chemical method for synthesizing FePt by adjusting the growth temperature. As a result, we have succeeded in synthesizing FePt nanoparticles with a controlled shape (cubic) and a uniform size (ca. 5.6 nm). [ABSTRACT FROM AUTHOR]

The Cover Feature shows that iron(III) aquo complexes can be used as a homogeneous photocatalysts for green fine chemical synthesis. In their Communication, M. F. Iqbal et al. demonstrate that the iron aquo complexes catalyze the oxidation of cyclohexane to cyclohexanol and cyclohexanone with a turnover number (TON) of 88 and a nearly 100% selectivity using O2 under irradiation of solar light, whereas existing TiO2 and α‐Fe2O3 heterogeneous photocatalysts showed low TON and no activity. These results show the potential of such simple iron ions as effective photocatalysts for practical organic synthesis. More information can be found in the Communication by M. F. Iqbal et al. on page 4509 in Issue 20, 2018 (DOI: 10.1002/cctc.201801360). [ABSTRACT FROM AUTHOR]