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Tetrahedron‐based nitrides offer a wide range of properties and applications. Highly condensed nitridophosphates are examples of nitrides that exhibit fascinating luminescence properties when doped with Eu2+, making them appealing for industrial applications. Here, we present the first nitridomagnesophosphate solid solution series Ba3−xSrx[Mg2P10N20] : Eu2+ (x=0–3), synthesized by a high‐pressure high‐temperature approach using the multianvil technique (3 GPa, 1400 °C). Starting from the binary nitrides P3N5 and Mg3N2 and the respective alkaline earth azides, we incorporate Mg into the P/N framework to increase the degree of condensation κ to 0.6, the highest observed value for alkaline earth nitridophosphates. The crystal structure was elucidated by single‐crystal X‐ray diffraction, powder X‐ray diffraction, energy‐dispersive X‐ray spectroscopy (EDX), and solid‐state NMR. DFT calculations were performed on the title compounds and other related highly condensed nitridophosphates to investigate the influence of Mg in the P/N network. Eu2+‐doped samples of the solid solution series show a tunable narrow‐band emission from cyan to green (492–515 nm), which is attributed to the preferred doping of a single crystallographic site. Experimental confirmation of this assumption was provided by overdoping experiments and STEM‐HAADF studies on the series as well on the stoichiometric compound Ba2Eu[Mg2P10N20] with additional atomic resolution energy‐dispersive X‐ray spectroscopy (EDX) mapping. [ABSTRACT FROM AUTHOR]

We present the first nitridic analogs of micas, namely AESi3P4N10(NH)2 (AE=Mg, Mg0.94Ca0.06, Ca, Sr), which were synthesized under high‐pressure high‐temperature conditions at 1400 °C and 8 GPa from the refractory nitrides P3N5 and Si3N4, the respective alkaline earth amides, implementing NH4F as a mineralizer. The crystal structure was elucidated by single‐crystal diffraction with microfocused synchrotron radiation, energy‐dispersive X‐ray spectroscopic (EDX) mapping with atomic resolution, powder X‐ray diffraction, and solid‐state NMR. The structures consist of typical tetrahedra–octahedra–tetrahedra (T‐O‐T) layers with P occupying T and Si occupying O layers, realizing the rare motif of sixfold coordinated silicon atoms in nitrides. The presence of H, as an imide group forming the SiN4(NH)2 octahedra, is confirmed by SCXRD, MAS‐NMR, and IR spectroscopy. Eu2+‐doped samples show tunable narrow‐band emission from deep blue to cyan (451–492 nm). [ABSTRACT FROM AUTHOR]

The recently introduced nitridophosphate synthesis in a hot isostatic press (HIP) enabled simple access to large‐scale product quantities starting from exclusively commercially available starting materials. Herein, we show that this method is suitable for the synthesis of highly condensed functional nitridophosphates, as well. Hence, the syntheses of the nitridophosphate zeolites Ba3P5N10X (X=Cl, Br) are presented as proof of concept for this innovative access. Furthermore, samples of unprecedented Sr3P5N10X (X=Cl, Br) were prepared and characterized to demonstrate the advantages of this synthetic approach over commonly used methods. Luminescence investigations on Eu2+‐doped samples of AE3P5N10X (AE=Sr, Ba; X=Cl, Br) were carried out and characteristics of observed emission bands are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Highly efficient phosphor‐converted light‐emitting diodes (pc‐LEDs) are popular in lighting and high‐tech electronics applications. The main goals of present LED research are increasing light quality, preserving color point stability and reducing energy consumption. For those purposes excellent phosphors in all spectral regions are required. Here, we report on ultra‐narrow band blue emitting oxoberyllates AELi2[Be4O6]:Eu2+ (AE=Sr,Ba) exhibiting a rigid covalent network isotypic to the nitridoalumosilicate BaLi2[(Al2Si2)N6]:Eu2+. The oxoberyllates’ extremely small Stokes shift and unprecedented ultra‐narrow band blue emission with fwhm ≈25 nm (≈1200 cm−1) at λem=454–456 nm result from its rigid, highly condensed tetrahedra network. AELi2[Be4O6]:Eu2+ allows for using short‐wavelength blue LEDs (λem<440 nm) for efficient excitation of the ultra‐narrow band blue phosphor, for application in violet pumped white RGB phosphor LEDs with improved color point stability, excellent color rendering, and high energy efficiency. [ABSTRACT FROM AUTHOR]