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A chemical reaction between Sb and N2 was induced under high‐pressure (32–35 GPa) and high‐temperature (1600–2200 K) conditions, generated by a laser heated diamond anvil cell. The reaction product was identified by single crystal synchrotron X‐ray diffraction at 35 GPa and room temperature as crystalline antimony nitride with Sb3N5 stoichiometry and structure belonging to orthorhombic space group Cmc21. Only Sb−N bonds are present in the covalent bonding framework, with two types of Sb atoms respectively forming SbN6 distorted octahedra and trigonal prisms and three types of N atoms forming NSb4 distorted tetrahedra and NSb3 trigonal pyramids. Taking into account two longer Sb−N distances, the SbN6 trigonal prisms can be depicted as SbN8 square antiprisms and the NSb3 trigonal pyramids as NSb4 distorted tetrahedra. The Sb3N5 structure can be described as an ordered stacking in the bc plane of bi‐ layers of SbN6 octahedra alternated to monolayers of SbN6 trigonal prisms (SbN8 square antiprisms). The discovery of Sb3N5 finally represents the long sought‐after experimental evidence for Sb to form a crystalline nitride, providing new insights about fundamental aspects of pnictogens chemistry and opening new perspectives for the high‐pressure chemistry of pnictogen nitrides and the synthesis of an entire class of new materials. [ABSTRACT FROM AUTHOR]

A chemical reaction between Sb and N2 was induced under high‐pressure (32–35 GPa) and high‐temperature (1600–2200 K) conditions, generated by a laser heated diamond anvil cell. The reaction product was identified by single crystal synchrotron X‐ray diffraction at 35 GPa and room temperature as crystalline antimony nitride with Sb3N5 stoichiometry and structure belonging to orthorhombic space group Cmc21. Only Sb−N bonds are present in the covalent bonding framework, with two types of Sb atoms respectively forming SbN6 distorted octahedra and trigonal prisms and three types of N atoms forming NSb4 distorted tetrahedra and NSb3 trigonal pyramids. Taking into account two longer Sb−N distances, the SbN6 trigonal prisms can be depicted as SbN8 square antiprisms and the NSb3 trigonal pyramids as NSb4 distorted tetrahedra. The Sb3N5 structure can be described as an ordered stacking in the bc plane of bi‐ layers of SbN6 octahedra alternated to monolayers of SbN6 trigonal prisms (SbN8 square antiprisms). The discovery of Sb3N5 finally represents the long sought‐after experimental evidence for Sb to form a crystalline nitride, providing new insights about fundamental aspects of pnictogens chemistry and opening new perspectives for the high‐pressure chemistry of pnictogen nitrides and the synthesis of an entire class of new materials. [ABSTRACT FROM AUTHOR]

A chemical reaction between Sb and N2 was induced under high‐pressure (32–35 GPa) and high‐temperature (1600–2200 K) conditions, generated by a laser heated diamond anvil cell. The reaction product was identified by single crystal synchrotron X‐ray diffraction at 35 GPa and room temperature as crystalline antimony nitride with Sb3N5 stoichiometry and structure belonging to orthorhombic space group Cmc21. Only Sb−N bonds are present in the covalent bonding framework, with two types of Sb atoms respectively forming SbN6 distorted octahedra and trigonal prisms and three types of N atoms forming NSb4 distorted tetrahedra and NSb3 trigonal pyramids. Taking into account two longer Sb−N distances, the SbN6 trigonal prisms can be depicted as SbN8 square antiprisms and the NSb3 trigonal pyramids as NSb4 distorted tetrahedra. The Sb3N5 structure can be described as an ordered stacking in the bc plane of bi‐ layers of SbN6 octahedra alternated to monolayers of SbN6 trigonal prisms (SbN8 square antiprisms). The discovery of Sb3N5 finally represents the long sought‐after experimental evidence for Sb to form a crystalline nitride, providing new insights about fundamental aspects of pnictogens chemistry and opening new perspectives for the high‐pressure chemistry of pnictogen nitrides and the synthesis of an entire class of new materials. [ABSTRACT FROM AUTHOR]

A chemical reaction between Sb and N2 was induced under high‐pressure (32–35 GPa) and high‐temperature (1600–2200 K) conditions, generated by a laser heated diamond anvil cell. The reaction product was identified by single crystal synchrotron X‐ray diffraction at 35 GPa and room temperature as crystalline antimony nitride with Sb3N5 stoichiometry and structure belonging to orthorhombic space group Cmc21. Only Sb−N bonds are present in the covalent bonding framework, with two types of Sb atoms respectively forming SbN6 distorted octahedra and trigonal prisms and three types of N atoms forming NSb4 distorted tetrahedra and NSb3 trigonal pyramids. Taking into account two longer Sb−N distances, the SbN6 trigonal prisms can be depicted as SbN8 square antiprisms and the NSb3 trigonal pyramids as NSb4 distorted tetrahedra. The Sb3N5 structure can be described as an ordered stacking in the bc plane of bi‐ layers of SbN6 octahedra alternated to monolayers of SbN6 trigonal prisms (SbN8 square antiprisms). The discovery of Sb3N5 finally represents the long sought‐after experimental evidence for Sb to form a crystalline nitride, providing new insights about fundamental aspects of pnictogens chemistry and opening new perspectives for the high‐pressure chemistry of pnictogen nitrides and the synthesis of an entire class of new materials. [ABSTRACT FROM AUTHOR]

Photocatalysts which are stable to photocorrosion and noble metal‐free, are highly desirable to achieve a light‐driven hydrogen production which satisfies the criteria of low production cost and environmental sustainability. Herein, a new heterostructure TiO2/BP/CoP has been developed, in which the BP nanosheets interact strongly with TiO2 and CoP, speeding up the transfer of photogenerated electrons and thus increasing H2 production. Once BP is added to TiO2 (P25) as only 1 % wt., the H2 evolution rate increases up to 4 times reaching a value of 830 μmol/g ⋅ h under UV‐Vis light irradiation. By integrating CoP nanoparticles as a cocatalyst up to 2 % wt., H2 production is further promoted to 7400 μmol/g ⋅ h, 37 times higher than pristine TiO2. Photoluminescence and electrochemical impedance measurements show that this heterostructure achieves a much more efficient charge separation and reduction of the internal resistance in comparison to pristine TiO2. Combining these data with UV‐Vis diffuse reflectance and Mott‐Schottky, a plausible mechanism was proposed. [ABSTRACT FROM AUTHOR]

Layered black phosphorus (BP) is endowed with peculiar chemico‐physical properties that make it a highly promising candidate in the field of electronics. Nevertheless, as other 2D materials with atomic scale thickness, it suffers from easy degradation under ambient conditions. Herein, it is shown that the functionalization of BP with preformed and in situ grown Ni NPs, affects the electronic properties of the material. In particular, Ni functionalization performed in situ leads to a narrowing of the average BP band gap from 1.15 to 0.95 eV and to a marked shift in the conduction band maximum from −0.33 V to −0.07 V, which, in turn, improve the ambient stability. Structural studies carried out by XAS can well distinguish the two nanohybrids and reveal that once Ni NPs are grown on BP nanosheets, a Ni‐P coordinative bond is formed, featuring a short Ni‐P distance of 2.27 Å, which is not observed when preformed Ni NPs are immobilized on BP. Comparing the XANES and EXAFS spectra of fresh and aged samples of both nanohybrids, suggests that the interaction between Ni and P atoms results in a stabilization effect exerted via a dual electronic and redox mechanism, that infers a much superior ambient stability to BP, even if the surface functionalization is far to achieve a full coverage. [ABSTRACT FROM AUTHOR]

Chemical reactivity between As and N2, leading to the synthesis of crystalline arsenic nitride, is here reported under high pressure and high temperature conditions generated by laser heating in a diamond anvil cell. Single‐crystal synchrotron X‐ray diffraction at different pressures between 30 and 40 GPa provides evidence for the synthesis of a covalent compound of AsN stoichiometry, crystallizing in a cubic P213 space group, in which each of the two elements is single‐bonded to three atoms of the other and hosts an electron lone pair, in a tetrahedral anisotropic coordination. The identification of characteristic structural motifs highlights the key role played by the directional repulsive interactions between non‐bonding electron lone pairs in the formation of the AsN structure. Additional data indicate the existence of AsN at room temperature from 9.8 up to 50 GPa. Implications concern fundamental aspects of pnictogens chemistry and the synthesis of innovative advanced materials. [ABSTRACT FROM AUTHOR]

Phosphorene, the 2D material derived from black phosphorus, has recently attracted a lot of interest for its properties, suitable for applications in materials science. The physical features and the prominent chemical reactivity on its surface render this nanolayered substrate particularly promising for electrical and optoelectronic applications. In addition, being a new potential ligand for metals, it opens the way for a new role of the inorganic chemistry in the 2D world, with special reference to the field of catalysis. The aim of this review is to summarize the state of the art in this subject and to present our most recent results in the preparation, functionalization, and use of phosphorene and its decorated derivatives. We discuss several key points, which are currently under investigation: the synthesis, the characterization by theoretical calculations, the high pressure behavior of black phosphorus, as well as its decoration with nanoparticles and encapsulation in polymers. Finally, device fabrication and electrical transport measurements are overviewed on the basis of recent literature and the new results collected in our laboratories. Black phosphorus and its exfoliated product, phosphorene, are rising stars in the 2D materials field. The role of inorganic chemistry is presented, the black phosphorus surface being a potential anchoring point for metal fragments. The applications of phosphorene and its functionalized derivatives in devices are also reported. [ABSTRACT FROM AUTHOR]

Black phosphorus was compressed at room temperature across the A17, A7 and simple-cubic phases up to 30 GPa, using a diamond anvil cell and He as pressure transmitting medium. Synchrotron X-ray diffraction showed the persistence of two previously unreported peaks related to the A7 structure in the pressure range of the simple-cubic phase. The Rietveld refinement of the data demonstrates the occurrence of a two-step mechanism for the A7 to simple-cubic phase transition, indicating the existence of an intermediate pseudo simple-cubic structure. From a chemical point of view this study represents a deep insight on the mechanism of interlayer bond formation during the transformation from the layered A7 to the non-layered simple-cubic phase of phosphorus, opening new perspectives for the design, synthesis and stabilization of phosphorene-based systems. As superconductivity is concerned, a new experimental evidence to explain the anomalous pressure behavior of Tc in phosphorus below 30 GPa is provided. [ABSTRACT FROM AUTHOR]

Water-soluble complexes cis-[Ru(bpy)2(PTA)2]Cl2 ( 1Cl2), cis-[Ru(bpy)2(PTA)2](PF6)2 [ 1(PF6)2], trans-[Ru(bpy)2(PTA)2](CF3SO3)2 [ 2(CF3SO3)2], cis-[Ru(bpy)2(PTA)(H2O)](CF3SO3)2 [ 3(CF3SO3)2], cis-[Ru(bpy)2(PTAH)(H2O)](CF3SO3)3 ·2CF3SO3H [ 4(CF3SO3)3 ·2CF3SO3H], cis-[Ru(bpy)2(PTAH)2](CF3SO3)4 ·4CF3SO3H [ 5(CF3SO3)4 ·4CF3SO3H], and trans-[Ru(bpy)2(PTAH)2](CF3SO3)4 ·4CF3SO3H [ 6(CF3SO3)4 ·4CF3SO3H] (bpy = 2,2′-bipyridyl; PTA = 1,3,5-triaza-7-phosphaadamantane) have been synthesized and characterized by elemental analysis, NMR, and IR spectroscopy. The crystal structures of 1(PF6)2, 2(CF3SO3)2, and 3(CF3SO3)2 were obtained by single-crystal X-ray diffraction. Both experimental and computational techniques were utilized to perform a detailed analysis of the structural and electronic properties of complexes 1 and 2 in water in both the deprotonated and protonated state and under N2 and air. Luminescence studies showed that these complexes are active fluorescence compounds, despite the presence of monophosphines in their structure. The pH sensitivity of the emission band of both complexes and their photohydrolysis in acidic water solution was studied. Both complexes release a PTA molecule under selective irradiation in acidic water to give complex 4. Cyclic voltammetry showed that, in water, irreversible anodic oxidation corresponding to the RuII/RuIII redox process occurs for 1, whereas for 2 the process is quasi-reversible, while in N, N-dimethylformamide for both complexes they are irreversible and occur at lower potential than in water. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the influence of the amount of water on the exfoliation and quality of phosphorene flakes. The liquid exfoliation was conducted in dimethylsulfoxide (DMSO) containing water with the use of an ultrasonication bath while keeping the suspension under nitrogen. The characterization of the black phosphorus (BP) nanoflakes was conducted by drop-casting the sol in the case of scanning electron microscopy and atomic force microscopy.

The water-soluble backbone heterometallic polymer {[(PTA)2CpRu-μ-CN-RuCp(PTA)2-μ-NiCl3]} n ( 2) is synthesized using a reproducible and robust method and fully characterized by X-ray single crystal diffraction. The Ru-Ru-Ni polymer is found to be stable in the solid state and soluble in water. Nuclear magnetic resonance (NMR) and light scattering studies show that the polymer is stable in water for several days in air. [ABSTRACT FROM AUTHOR]

White phosphorus (P4) is a small molecule that is mainly used as a starting material for the large-scale synthesis of most of the suitable phosphorus derivatives. The process starts with the direct reaction of P4 with Cl2, and the resulting phosphorus chloride is further treated with the adequate organic substrate. This industrial process is very primitive, and for economic and environmental reasons the first oxidation step should be avoided. The observation that the conversion of white P4 to the red allotrope is accelerated by ultraviolet light showed that the P4 molecule is able to be activated by electromagnetic radiation. Metal complexes can also mediate the functionalization of P4. The participation of electromagnetic radiation in the reactions that involve P4 and metal complexes has provided new procedures for obtaining new and interesting compounds that contain phosphorus atoms. Very significant and interesting reviews have summarized, classified and discussed the reactivity of P4 but until now none of them have distilled the relationship between white phosphorus and electromagnetic radiation. [ABSTRACT FROM AUTHOR]

The new water-soluble palladium(II) complexes Na2{ trans-[PdCl2(mTPPMS-κ P)2]} ( 1), (CN4H7)Na{ trans-[PdCl2(mTPPMS-κ P)2]} ( 2) and the 2D polymer trans-{Pd-μ-[mTPPMS-1κ P:2κ O-Na1/2(H2O)]-μ-[mTPPMS-1κ P:2κ O′-Na′1/2(H2O)]-μ-[8TTH-1κ S:2κ O6 -Na1/2(H2O)]-μ-[8TTH-1κ S:2κ O6-Na′1/2(H2O)]} n ( 3) {mTPPMS = Ph2P[3-OS(O)2C6H4]-; 8-TTH = 8-thiotheophyllinate} have been synthesized and characterised by NMR and IR spectroscopy as well as elemental analysis. The crystal structures of 2 and 3 were determined by X-ray diffraction. The binding properties of the new hydrosoluble palladium complexes towards DNA were studied by the mobility shift assay, which showed that complex 1 is more active than cisplatin towards DNA. [ABSTRACT FROM AUTHOR]

New 2D black phosphorus (bP)–phthalocyanine (Pc) nanohybrids have been synthesized by liquid phase exfoliation of black phosphorus crystals in the presence of two organic dyes: phthalocyanine (Pc) and manganese phthalocyanine (MnPc). The key role of the metal cation in the interfacial interaction between the organic dye and bP nanosheets was demonstrated by X‐ray absorption spectroscopy and associated with an electron transfer between the metal cation Mn2+ and bP nanosheets, which resembles a coordinative chemical bond. On the other hand, the interaction between bP nanosheets and pure phthalocyanine is governed by van der Waals forces. The fluorescence of both hybrids is significantly reduced indicating effective separation of the photoinduced charge, implying the formation of a heterojunction between the organic molecules and the bP nanosheets. These findings provide important insights into the interfacial interactions in bP‐Pc nanohybrids that are relevant for application in 2D organic/inorganic devices. [ABSTRACT FROM AUTHOR]

Resistivity measurements of a black phosphorus (bP) field‐effect transistor 16 nm thick in parallel magnetic fields up to 45 T are reported as a function of the angle between the in‐plane field and the source–drain (S–D) axis of the device. The crystallographic directions of the bP crystal are determined by Raman spectroscopy, with the zigzag axis found to be within 5° of the S–D axis and the armchair axis in the orthogonal planar direction. A transverse magnetoresistance (TMR) as well as a classically forbidden longitudinal magnetoresistance (LMR) are observed. Both are found to be strongly anisotropic and nonmonotonic with increasing in‐plane field. Surprisingly, the relative magnitude (in %) of the positive LMR is larger than the TMR above ≈32 T. Considering the known anisotropy of bP whose zigzag and armchair effective masses differ by a factor of ≈7, the experiment strongly suggests this LMR to be a consequence of the anisotropic Fermi surface of bP. [ABSTRACT FROM AUTHOR]