Ammonothermal Synthesis of Nitrides: Recent Developments and Future Perspectives

Abstract

Nitrides represent an intriguing class of functional materials with a broad range of application fields. Within the past decade, the ammonothermal method became increasingly attractive for the synthesis and crystal growth of nitride materials. The ammonothermal approach proved to be eminently suitable for the growth of bulk III-nitride semiconductors like GaN, and furthermore provided access to numerous ternary and multinary nitrides and oxonitrides with promising optical and electronic properties. In this minireview, we will shed light on the latest research findings covering the synthesis of nitrides by this method. An overview of synthesis strategies for binary, ternary, and multinary nitrides and oxonitrides, as well as their properties and potential applications will be given. The recent development of autoclave technologies for syntheses at high temperatures and pressures, in situ methods for investigations of crystallization processes, and solubility measurements by ultrasonic velocity experiments is briefly reviewed as well. In conclusion, challenges and future perspectives regarding the synthesis and crystal growth of novel nitrides, as well as the advancement of autoclave techniques are discussed.

Ammonothermal Synthesis of the Mixed‐Valence Nitrogen‐Rich Europium Tantalum Ruddlesden‐Popper Phase EuIIEuIII2Ta2N4O3

“…Eu II Eu III 2 Ta 2 N 4 O 3 was synthesized by an ammonothermal approach using custom‐built high‐temperature autoclaves made of nickel‐based superalloy , . Metallic Ta and Eu were used as powders.…”

“…Since the pioneering work of Jacobs and Juza in the 1960s, the ammonothermal method has emerged as a versatile synthetic approach for a broad spectrum of compounds, e.g. amides, imides, nitrides, hydroxides and chalcogenides . Despite this synthetic potential, synthesis in supercritical ammonia has been predominantly employed for crystal growth of GaN targeting appropriate substrate crystals for homoepitaxial growth of this important wide band gap semiconductor .…”

“…Recently, the ammonothermal approach has again been utilized for explorative synthetic solid‐state chemistry of novel complex nitrides, e.g. CaGaSiN 3 , ZnSiN 2 , ZnGeN 2 , Zn 2 PN 3 as well as nitride oxide perovskites such as Ln TaN 2 O with Ln = La, Ce, Pr, Nd, Sm and Gd and EAM NO 2 with EA = Sr, Ba and M = Nb, Ta , . Novel materials with mixed anions such as nitride oxides came into research focus in the last decade.…”

Nitridophosphates: A Success Story of Nitride Synthesis

“…[48] Moreover,i na utoclaves large quantities can be prepared at once,w hich is relevant for industrial upscaling.I n1 997, Jacobs and co-workers prepared HPN 2 / DPN 2 by ammonolysis of P 3 N 5 at 550 8 8Ca nd 600 MPa, and K 3 P 6 N 11 from P 3 N 5 and KNH 2 at 500 8 8Ca nd 600 MPa. [33,50] With these autoclaves,Z n 2 PN 3 and Mg 2 PN 3 have recently been prepared from P 3 N 5 and metal amides,the latter in the form of single crystals of up to 30 mmi nlength (Figure 8). 600 8 8C, 0.3 GPa) and Haynes 282 (max.…”

Crystalline Nitridophosphates by Ammonothermal Synthesis

“…[1][2][3][4][5] The ammonothermal technique gainedf undamentali nterest in materials science as it facilitates the growth of high-quality GaN single crystalsu pt o 50 mm in diameter with growth rates of several hundred mm per day. [1][2][3][4][5] The ammonothermal technique gainedf undamentali nterest in materials science as it facilitates the growth of high-quality GaN single crystalsu pt o 50 mm in diameter with growth rates of several hundred mm per day.…”