The atlas of ferroicity in two-dimensional MGeX3 family: Room-temperature ferromagnetic half metals and unexpected ferroelectricity and ferroelasticity

Two-dimensional (2D) ferromagnetic and ferroelectric materials attract unprecedented attention due to the spontaneous-symmetry-breaking induced novel properties multifarious potential applications. Here we systematically investigate a large family (148) of 2D MGeX3 (M = metal elements, X O/S/Se/Te) by means high-throughput first-principles calculations, focus on their possible ferroic including ferromagnetism, ferroelectricity, ferroelasticity. We discover eight stable ferromagnets five semiconductors three half-metals, 21 antiferromagnets, 11 two multiferroic materials. Particularly, MnGeSe3 MnGeTe3 are predicted be room-temperature half metals with Tc 490 308 K, respectively. It is probably for first time that ferroelectricity uncovered in family, which derives from spontaneous symmetry breaking unexpected displacements Ge-Ge atomic pairs, also reveal electric polarizations proportion ratio electronegativity M atoms, IVB group elements highly favored ferroelectricity. Magnetic tunnel junction water-splitting photocatalyst based proposed as examples wide The atlas ferroicity will spur great interest experimental studies would lead diverse