Surface Coordination Modulated Morphological Anisotropic Engineering of Iron-Benzoquinone Frameworks for Lithium-Ion Batteries.

Abstract

Morphological anisotropic engineering is powerful to synthesize metal-organic frameworks (MOF) with versatile physicochemical properties for diverse applications ranging from gas storage/separation to electrocatalysis and batteries, etc. Herein, we developed a carbon substrate guided strategy for facet-anisotropic growth of Fe-THBQ (tetrahydroxy-1,4-benzoquinone) frameworks, which is built with cubic Fe octamer bridged by two parallel THBQ ligands along three orthogonal axes, extending to a three-dimensional (3D) framework with pcu-e network topology. The electronegative O-containing functional groups on carbon surfaces compete with THBQ linkers to interact with the unsaturated coordinated Fe cations on the {111} facets and selectively inhibit crystal growth along the <111> direction. The morphology of Fe-THBQ evolves from thermodynamically favored truncated cube to cuboctahedron depending on the O-containing functional groups on carbon substrate. The Fe-THBQ with varied morphologies exhibits facet-dependent performances for lithium storage. This work will shed lights on morphology modulation of MOFs for promising applications.