Chemical order or disorder – a theoretical stability expose for expanding the compositional space of quaternary metal borides. Issue 6 (24th February 2022)

• Record Type: Journal Article
• Authors: Dahlqvist, Martin; Rosen, Johanna
• Is Part Of: Materials advances. Volume 3:Issue 6(2022)
• Page Start: 2908
• Page End: 2917
• Publication Date: 2022-02-24
• Subjects: 620.11
• DOI: 10.1039/d1ma01076j
• Languages: English
• ISSNs: 2633-5409

Abstract

Abstract : Theoretical predictions for finding thermodynamically stable quaternary MAB phases upon metal alloying. Abstract : Inspired by the recent discovery of Ti4 MoSiB2, a quaternary phase with out-of-plane chemical order that we denote as o -MAB, we perform an extensive first-principles study to explore the attained chemical order and disorder (solid-solution) upon metal alloying of M5 AB2 (T2 phases), with M from Groups 3 to 9 and A = Al, Si, P, Ga, and Ge. We show that the attainable chemistries of T2 can be significantly expanded and predict 35 chemically ordered o -MAB phases and 121 solid solutions of an M′′AB2 stoichiometry. The possibility of realizing o -MAB or solid solution MAB phases combined with multiple elemental combinations previously not observed in these borides suggests an increased property tuning potential. Furthermore, five ternary T2 phases, yet to be synthesized, are also predicted to be stable.