Non-linear dielectric response of layered CuInP₂S₆ and Cu_0.9Ag_0.1InP₂S₆ crystals

Spin evolution and flip in the oxygen reduction reaction: a theoretical study of Cu(Ni)XP2S6(X = In, Bi and Cr)

“…5,7,11 M 2 P 2 Y 6 (M: Sc, Fe, Sc/Cr, Cu/Cr, Cu/In, Cu/Bi, Ag/Bi, etc. ; Y: S, Se, Te), a family of 2D layered materials, have recently attracted a lot of attention because of their abundant compositions [32][33][34][35][36] and promising applications in catalytic reactions, such as the ORR, oxygen evolution reaction (OER) and CO 2 reduction reaction (CO 2 RR). [37][38][39][40][41] M can be one element, such as Fe in Fe 2 P 2 S 6 that is active for the CO 2 RR, 39 or two different elements, such as Cu and In in CuInP 2 S 6 that is ferroelectric and catalytically active for the CO 2 RR too.…”

“…However, the bulk CuCrP 2 S 6 is antiferromagnetic. 35,43 Dopants and vacancies in M 2 P 2 Y 6 are possibly introduced during the preparation, 34,44 which could modify the magnetic and electronic properties and active sites for catalysis. 34,38,45 The diverse magnetic and electronic properties may provide a platform to study the spin transportation and evolution in the catalytic reactions.…”

Stress-induced phase transitions in nanoscale CuInP2S6

“…The CuInP2(S,Se)6 family reveals very unusual features of a nonlinear dielectric response indicating that a spontaneous polarization may exist above the transition temperature [32], extremely large elastic nonlinearity in the direction perpendicular to the layers [33,34], a giant negative electrostriction and dielectric tunability [35], the electrostriction induced piezoelectricity above the ferroelectric transition temperature [36], morphotropic phase transitions between its monoclinic and trigonal phases [37], and anomalous "bright" domain walls with enhanced local piezoelectric response [38,39].…”

Anharmonic stabilization of ferrielectricity in CuInP$_2$Se$_6$

“…Of those, the transition metal thiophosphates are a promising family of materials that host out-of-plane ferrielectricity (FiE) with large values of polarization [6,11,12]. Further, research efforts in these materials have reported a plethora of properties including negative piezoelectricity, negative electrostriction, large dielectric tunability, and unconventional field-induced switching behavior, all of which depend strongly on the polarization [13][14][15][16][17][18][19][20][21][22][23]. Despite the growing interest, a clear understanding of the origin and stabilization of the polar phase is still lacking in transition metal thiophosphate.…”