Strategies to achieve reproducible synthesis of phase-pure Zr-porphyrin metal-organic frameworks

Porphyrin-based metal-organic frameworks (MOFs) are gaining traction for various applications due to their sorption, optoelectronic and catalytic properties. MOFs with Zr-based nodes constitute a particularly robust and versatile class of MOFs in which incorporation of metals into the porphyrin core allows further tuning of their physico-chemical properties. However, significant challenges regarding the phase-pure synthesis of Zr-porphyrin MOFs have slowed down progress in the field. Synthetic challenges in targeted phase formation originate from the densely populated phase space, due to energetically similar framework topologies accessible from the same building blocks, but also from the lack of detailed synthetic information. This Perspective discusses different synthetic approaches and detailed synthesis investigations to gain a deeper understanding while providing strategies towards suitable conditions to access phase-pure Zr-porphyrin MOFs. Transparent data reporting and holistic consideration of synthetic factors may allow for better control of these aspects. This is crucial for the establishment of structure–property relationships in such materials and will facilitate the realisation of their application potential. Synthesizing phase-pure zirconium-porphyrin metal-organic frameworks is challenging. This Perspective discusses different synthetic approaches and investigations to guide conditions to achieve phase-pure zirconium-porphyrin metal-organic frameworks.