Microstructural Engineering of Conductive MOF Nanocrystals for Multifunctional Heterostructures.

Abstract

Conductive metal-organic frameworks (cMOFs) have emerged as transformative materials, significantly expanding the functional landscape of conventional MOFs by integrating electrical conductivity. Despite this, harnessing their full potential in heterostructured architectures is constrained by challenges in finely tuning the critical structural parameters, notably the packing density and crystallographic orientation. This paper introduces an innovative approach to engineering the microstructure of cMOFs as conformal shell-enveloping spherical nanoparticles. The compactness of the cMOF layer is modulated by the crystallization kinetics, while a deliberate seeding process directed the alignment of cMOF nanocrystallites. These methodologies collectively facilitated the formation of densely packed, highly ordered nanocrystallite assemblies in a core-shell configuration, enhancing mechanical robustness, selective permeability, and electron transport. The resulting cMOF assembly markedly augmented the stability and electrochemical performance of the sulfur core, showing significant promise as a next-generation cathode material for lithium-sulfur batteries.