The amalgamation of different disciplines is at the heart of reticular chemistry and has broadened the boundaries of chemistry by opening up an infinite space of chemical composition, structure, and material properties. Reticular design has enabled the precise prediction of crystalline framework structures, tunability of chemical composition, incorporation of various functionalities onto the framework backbone, and as a consequence, fine‐tuning of metal–organic framework (MOF) and covalent organic framework (COF) properties beyond that of any other material class. Leveraging the unique properties of reticular materials has resulted in significant advances from both a fundamental and an applied perspective. Here, we wish to review the milestones in MOF and COF research and give a critical view on progress in their real‐world applications. Finally, we briefly discuss the major challenges in the field that need to be addressed to pave the way for industrial applications.

Christian Diercks studierte Chemiea nder UniversitätHeidelberg und führte im Grundstudium Forschungsarbeiten in der Gruppe von Prof. Jean-Pierre Sauvage an der Univer-sitätStraßburg sowie an der Northwestern University unter der Leitung von Sir James F. Stoddart durch. Seinen Ph.D. erhielt er 2018 an der UC Berkeley unter der Betreuung von Prof. Omar M. Yaghi fürs eine Arbeit über kovalente organischeG erüstverbindungen. Derzeit ist er Postdoktorandin der Gruppe von Prof. Peter G. Schultz am Scripps Research Institut und arbeitet daran, die Prozesse des zentralen Dogmas der Molekularbiologie um neue Chemien zu erweitern. Stefan Wuttke gründete die Arbeitsgruppe "WuttkeGroup for Science", welche zunächst am Lehrstuhl fürP hysikalische Chemie an der UniversitätMünchen (LMU) angesiedelt war.D erzeit ist er ein Ikerbasque Professor am BaskischenZ entrum fürMaterialien, Anwendungen und Nanostrukturen (BCMaterials, Spanien).S eine Forschung konzentriert sich auf die Entwicklung von Methoden zum Schreiben und Lesen chemischer Informationen auf und aus dem Rückgrat von hybriden Gerüstmaterialien. Darüber hinaus umfassen seine Forschungsinteressen das Verständnisder chemischen und physikalischen Prozesse,d ie an ihrer Synthese und Funktionalisierung beteiligt sind. Abbildung 1. Charakteristische Merkmale von MOFsund COFs: I) Bauplan;I I) einstellbare Porosität; III) postsynthetische Modifikation zur Veränderung von Gerüst-Gast-Wechselwirkungen;IV) multivariate Funktionalisierung;V )einfache Charakterisierung;und VI) skalierbare Synthese.

Crystalline coordination polymers with high electrical conductivities and charge carrier mobilities might open new opportunities for electronic devices. However, current solvent-based synthesis methods hinder compatibility with microfabrication standards. Here, we describe a solvent-free chemical vapor deposition method to prepare high-quality films of the two-dimensional conjugated coordination polymer Cu-BHT (BHT = benzenehexanothiolate). This approach involves the conversion of a metal oxide precursor into Cu-BHT nanofilms with a controllable thickness (20–85 nm) and low roughness (<10 nm) through exposure to the vaporized organic linker. Moreover, the restricted metal ion mobility during the vapor–solid reaction enables high-resolution patterning via both bottom-up lithography, including the fabrication of micron-sized Hall bar and electrode patterns to accurately evaluate the conductivity and mobility values of the Cu-BHT films.

Because of their guest adsorption properties, metal–organic frameworks (MOFs) are promising materials to realize chemical sensors. However, achieving high sensitivities requires the reproducible deposition of well-defined MOF films and their integration with a suitable sensor design. In this work, we report the sensitive detection of volatile organic compounds (VOCs) by transducing the adsorption in zeolitic imidazolate framework 8 (ZIF-8) thin films, prepared by chemical vapor deposition (MOF-CVD), into surface plasmon polariton (SPP) shifts measured via total internal reflection ellipsometry (TIRE). It is shown that defect formation during MOF-CVD alters the VOC uptake. However, SPP resonances tunable over the entire Vis–NIR range and as sharp as 14 nm are obtained for optimized synthesis conditions. Record-breaking shifts stronger than 150 nm upon methanol uptake and a limit of detection below 1 ppm are observed. By modeling the TIRE spectra, changes in the ZIF-8 refractive index from 1 × 10–4 (single-digit ppm VOC concentration) up to 0.06 are resolved with a resolution better than 1 × 10–5.

Vapor-phase film deposition of metal–organic frameworks (MOFs) would facilitate the integration of these materials into electronic devices. We studied the vapor-phase layer-by-layer deposition of zeolitic imidazolate framework 8 (ZIF-8) by consecutive, self-saturating reactions of diethyl zinc, water, and 2-methylimidazole on a substrate. Two approaches were compared: (1) Direct ZIF-8 “molecular layer deposition” (MLD), which enables a nanometer-resolution thickness control and employs only self-saturating reactions, resulting in smooth films that are crystalline as-deposited, and (2) two-step ZIF-8 MLD, in which crystallization occurs during a postdeposition treatment with additional linker vapor. The latter approach resulted in a reduced deposition time and an improved MOF quality, i.e., increased crystallinity and probe molecule uptake, although the smoothness and thickness control were partially lost. Both approaches were developed in a modified atomic layer deposition reactor to ensure cleanroom compatibility.