Compositional defects in a MoAlB MAB phase thin film grown by high-power pulsed magnetron sputtering

Abstract

Various compositional defects such as Mo3Al2B4, Mo4Al3B4, Mo6Al5B6 and Al3Mo, together with MoB MBene, are observed to be coexisting in a MoAlB MAB phase thin film grown at 800 °C by high-power pulsed magnetron sputtering.

MBene with Redox‐Active Terminal Groups for an Energy‐Dense Cascade Aqueous Battery

“…[10][11][12][13] MBenes, a new family of 2D materials derived from the parent MAB (where "M" is the early transition metal, "A" is the metal from groups IIIA and IVA of the periodic table, and "B" is the boron element), [14][15][16][17] hold even brighter prospects for energy storage, owing to their electronically conductive skeleton, high chemical activity, and fast charge carrier mobility. [14,16,17] At present, the synthesis of MBenes can be mainly cataloged into six methods: [16][17][18][19] i) thermal fragmentation, for example, synthesizing MnB MBene through a reaction between Mn and B powder at 5.0 GPa and 1400 K; [20] ii) chemical reduction, for example, synthesizing FeB 2 MBene through the reaction between FeSO 4 •7H 2 O and LiBH 4 under Ar protection; [21] iii) thin-film deposition, for example, synthesizing MoB MBene from a MoAlB film grown by sputtering at 973 K in a 0.4-Pa Ar atmosphere; [22,23] iv) dealloying, for example, synthesizing TiB MBene by dealloying In from Ti 2 InB 2 at 1323 K under a high vacuum for several days; [24] v) mechanical exfoliation, for example, synthesizing MnB 2 MBene by exfoliating MnB 2 bulk powder through a microwave-assisted route; [25] and vi) wet etching, for example, synthesizing MBene (e.g., MoB, [26][27][28] MnB, [29] or CrB [30] ) by removing the interlayered "A" from the parent MAB phase using an HF, HCl/LiF, HCl, HCl/H 2 O 2 , or NaOH solution. Apart from the wet etching method, MBenes synthesized using the above methods are almost bare, without surface terminations.…”