Enhanced stability and energy performance in energetic metal-organic frameworks enabled by dimensional isomerism

Abstract

High-energy crystallographic frameworks present both opportunities and challenges. While isomerization is a key strategy in designing energetic molecules, its application in energetic metal–organic frameworks (EMOFs) is underexplored. Here, we report the first crystallization of framework dimensional isomers in EMOFs, self-assembled from the same building blocks. Using 4,4′-diamino-[3,3′-bi(1,2,4-oxadiazole)]-5,5′(4H,4′H)-dione (DABOD) as a ligand, two isomers of Ag(DABOD)ClO₄-1 with a 2D framework and Ag(DABOD)ClO₄-2 with a 1D framework were prepared, by altering the solution environment. Detailed structural analyses show that different coordination sites of organic linkers and different coordination modes of metal atoms result in forming framework structures with different dimensions. Notably, 2D EMOF exhibits enhanced stability and energy performance compared to 1D EMOF, breaking through the limitations of the traditional dimensionality enhancement strategy. Both EMOFs demonstrate good detonation properties and laser ignition capabilities, indicating promising applications. This study injects fresh blood into the development of energetic materials and provides an important reference for exploring structure–property relationships.