Discovery of Ternary Silicon Titanium Nitride with Spinel-Type Structure

Shrikant Bhat , Abhijeet Lale (1) , Samuel Bernard (1) , Wei Zhang (2) , Ryo Ishikawa , Shariq Haseen , Peter Kroll , Leonore Wiehl , Robert Farla (3) , Tomoo Katsura (4) , Yuichi Ikuhara (5) , Ralf Riedel (6)

1 IRCER-AXE4 - IRCER - Axe 4 : céramiques sous contraintes environnementales
2 IFPRI - International Food Policy Research Institute [Washington]
3 BGI - Bayerisches Geoinstitut
4 Institute for Study of the Earth's Interior, Okayama University
5 The University of Tokyo, School of Engineering
6 TU Darmstadt - Technische Universität Darmstadt - Technical University of Darmstadt

Here we report on the discovery of a ternary silicon titanium nitride with the general composition (Si 1−x ,ti x) 3 n 4 with x = 0 < x < 1 and spinel-type crystal structure. The novel nitride is formed from an amorphous silicon titanium nitride (Sitin) precursor under high-pressure/high-temperature conditions in a large volume high-pressure device. Under the conditions of 15-20 GPa and 1800-2000 °C, spineltype γ-Si 3 n 4 and rock salt-type c-TiN are formed. In addition, crystals of the discovered nano-sized ternary phase (Si 1−x ,ti x) 3 n 4 embedded in γ-Si 3 n 4 are identified. The ternary compound is formed due to kinetically-controlled synthesis conditions and is analyzed to exhibit the spinel-type structure with ca. 8 atom% of Ti. The Ti atoms occur in both Ti 3+ and ti 4+ oxidation states and are located on the Si sites. the ternary nano-crystals have to be described as (Si,ti) 3 n 4 with n-vacancies resulting in the general composition (Si 4+ 1−x ti 4+ x-δ ti 3+ δ) 3 n 4-δ .

Domaines: Chimie; Matériaux

Shrikant Bhat, Abhijeet Lale, Samuel Bernard, Wei Zhang, Ryo Ishikawa, et al.. Discovery of Ternary Silicon Titanium Nitride with Spinel-Type Structure. Scientific Reports, 2020, 10 (1), ⟨10.1038/s41598-020-64101-5⟩. ⟨hal-02613606⟩