Unprecedented Zeolite-Like Framework Topology Constructed from Cages with 3-Rings in a Barium Oxonitridophosphate

Abstract

Classical zeolites, such as aluminosilicates and aluminophosphates, are well-established in fundamental industrial processes, e.g., substance separation, air and water conditioning, or catalysis. As they have the potential for further applications in future technologies (e.g., sensors, electronic, or optical systems), inorganic open-framework materials emerged as a research area with a multitude of compound classes in the last decades. In addition to diverse metal phosphates, germanates, and borates, there are sulfates, arsenates, or phosphonates as well as organicÀinorganic hybrid compounds with porous networks. 1,2 However, many microporous structures are thermally and chemically not sufficiently stable to make their way toward advanced materials. Consequently, it is worthwhile to synthesize novel open-framework materials that exhibit three-dimensional, rigid framework structures based on vertex-sharing tetrahedra. Since the discovery of the aluminophosphates by Flanigen et al. 3 in the 1980s, it has been attempted with great creativity and effort to access new stable frameworks with different pore sizes and shapes combined with varying chemical and physical properties. Different synthesis conditions (temperature, reaction time, pH), many different structure-directing agents (SDA), as well as a broad spectrum of solvents, including ionic liquids, were employed. The fluoride route 4 has been utilized, and other tetrahedra centers (e.g., B, Ga, Zn) were included, resulting in new zeotypes in compound classes like silicoaluminophosphates (SAPOs) and metal-containing versions (e.g., MeAPO, MeAPSO) thereof. 2,5 Thus, the field of zeolite chemistry seems quite mature which means that the search for new framework types becomes increasingly challenging.The exchange of oxygen by nitrogen in the anionic substructure is an innovative but rarely realized expansion of zeolite chemistry. Nitrido-zeolites promise beneficial chemical and physical properties (e.g., higher thermal stability or adjustable acidity/basicity) and a huge structural diversity. As compared with oxygen, nitrogen atoms are more common in three-binding situations, and they provide more flexibility as bridging atoms in networks by occasionally realizing smaller angles TÀXÀT (X = O, N). Consequently, both large rings as well as rare 3-rings can be stabilized so that novel zeolite-like frameworks become possible.This nitride concept became reality in (oxo-)nitridosilicates and (oxo-)nitridophosphates. After the proof of concept with nitridosodalites 6 and related oxonitridosodalites, 7 the benefits of nitrogen in zeolite-like framework structures have been demonstrated only for very few examples. Besides a zeolite-like SiÀN framework in Ba 2 Nd 7 Si 11 N 23 with a notable thermal stability up to 1600°C, 8 the flexibility of N bridging resulted in Li x H 12ÀxÀy+z - [P 12 O y N 24Ày ]X z for X = Cl, Br with a new zeolite topology, namely, NPO (nitridophosphate one). 9 The typical (ring-)strain Received: March 20, 2011 ABSTRACT: A novel oxonitridophospha...

SrP3N5O: A Highly Condensed Layer Phosphate Structure Solved from a Nanocrystal by Automated Electron Diffraction Tomography

“…0.4582(6) 3 = 4 0.5686(10) 0.069(3) Sr(3) [6] 4c 0.1801(6) 1 = 4 0.4187(13) 0.082(4) Sr(4) [9] 4c 0.4352(10) 1 = 4 0.9874(11) 0.093(5) P(1) [4] 8d 0.6162(6) 0.4314(11) 0.8601(9) 0.053(3) P(2) [4] 8d 0.6524(6) 0.5672(12) 0.5262(10) 0.056(3) P(3) [4] 8d 0.5549(6) 0.4329(11) 0.6729(9) 0.050(3) P(4) [4] 8d 0.7062(6) 0.4296(12) 0.6938(10) 0.058(4) P(5) [4] 8d 0.4709(6) 0.5617(11) 0.8288(10) 0.052(3) P(6) [4] 8d 0.2575(9) 0.9298(16) 0.6378(13) 0.102(7) N(1) [3] -type tetrahedra) in which every O bridges two tetrahedra. [1] Applying this concept to the title compound with k = 1 = 2 , one would expect a three-dimensional network of all-side vertex-sharing PA C H T U N G T R E N N U N G (O,N) 4 tetrahedra.…”

Ba3P5N10Br:Eu2+: A Natural‐White‐Light Single Emitter with a Zeolite Structure Type

“…[16,31] However, by this procedure Ba 3 P 5 N 10 Br was only accessible as a minor side phase. [16,31] However, by this procedure Ba 3 P 5 N 10 Br was only accessible as a minor side phase.…”

“…[1][2][3][4][5][6] Prominent examples of the commercially most important functional zeolites are Na x (H 2 O) 16 Al x Si 96-x O 192 (x < 27; ZSM-5) and Na 12 (H 2 O) 27 [Al 12 Si 12 O 48 ] 8 (LTA), which exhibit excellent chemical and thermal stability. Classical zeolites, such as aluminosilicates and aluminophosphates, are widely used, for example in the fields of petroleum refining, in the petrochemical and fine chemical industry as adsorbents, and as ion exchangers or catalysts.…”

“…[9,10] Given that the element combination P/N is isoelectronic to Si/O, it is reasonable to expect that the resulting compound class of nitridophosphates exhibits a structural variety similar to or even more diverse than that of silicates. [14][15][16][17] As a result of their high thermal and chemical stability as well as highly cross-linked network structures, nitridic zeolites are basically well suited as host lattices for Eu 2+ doping. The structural diversity of oxosilicates is limited to terminal or singly bridging O atoms, whereas N atoms in nitridophosphates may occur as N [1] , N [2] , N [3] , or even N [4] atoms.…”

Nitridophosphate – eine Erfolgsgeschichte der Nitridsynthese

“…[38,40,42,43] Der erhçhte Ammoniakdruck und die zusätzlich zugegebenen Ammoniumhalogenide begünstigen jedoch die Kristallisation der Nitridophosphate.N eben den Raumnetzen niedriger Dichte von NPO und NPT konnten durch ähnliche Kondensationsreaktionen auch dichtere Te traedernetzwerke wie in SrP 3 N 5 O und Ba 6 P 12 N 17 O 9 Br 3 erhalten werden (Abbildung 7). [38,40,42,43] Der erhçhte Ammoniakdruck und die zusätzlich zugegebenen Ammoniumhalogenide begünstigen jedoch die Kristallisation der Nitridophosphate.N eben den Raumnetzen niedriger Dichte von NPO und NPT konnten durch ähnliche Kondensationsreaktionen auch dichtere Te traedernetzwerke wie in SrP 3 N 5 O und Ba 6 P 12 N 17 O 9 Br 3 erhalten werden (Abbildung 7).…”