“One stone two birds” design of borates featuring edge-sharing [BO4] and different B–O configurations in one structure utilizing covalent tetrahedra

Abstract

Two borates, K₃Al₂B₁₁O₂₁ (KABO) and K₃Al₂MoB₉O₂₁ (KAMBO), with edge-sharing [BO₄] (ES-[BO₄]) tetrahedra and different B–O configurations in one structure, were rationally designed and prepared at atmospheric pressure by introducing covalent tetrahedra. KABO is the first borate identified to have ES-[BO₄] tetrahedra and two different dimensional B–O groups, namely, isolated [B₆O₁₂] groups with ES-[BO₄] and one-dimensional infinite chains. In addition, KAMBO is a rare borate that features ES-[BO₄] tetrahedra and two distinct isolated B–O groups ([B₆O₁₂] and [B₃O₆]). The discovery of these two compounds not only enriches the structures of borates, but also suggests a novel method for creating borates with ES-[BO₄] tetrahedral structures and flexible B–O configurations at atmospheric pressure.