Hydrogen‐Bonded Organic Frameworks as an Appealing Platform for Luminescent Sensing

Abstract

Hydrogen‐bonded organic frameworks (HOFs), a novel subclass of porous crystalline materials self‐assembled from organic linkers through hydrogen bonding and other intermolecular interactions, have emerged as an exciting platform for developing multifunctional materials. Recently, luminescent HOF sensors have drawn considerable attention due to their unique advantages, such as hydrogen‐bonding flexibility, inherent luminescent centers in organic linkers, ease of functionalization, low density and toxicity, and good stability. However, a comprehensive study on the design strategies, functionalities, and applications of HOFs in sensing is lacking. In this review, the uniqueness and development of luminescent sensing HOFs are outlined. The design principles and strategies to enable the sensing performance are summarized, including the pre‐design of luminescent organic linkers and post‐modification with additional luminescent species. The state‐of‐the‐art advances in diverse sensing applications are overviewed, such as the detection of chemical pollutants, biomolecules, gases, and physical factors like temperature and mechanical forces. Moreover, the current challenges and corresponding potential avenues are discussed. This review aims to inspire more innovative research on the fabrication of advanced HOFs for luminescent sensing functions.

Unravelling the photobehavior of a 2,1,3-benzothiadiazole-based HOF and its molecular units: experimental and theoretical insights into their spectroscopic properties in solution and in the solid state

“…In the last decade, HOFs have emerged as new porous materials with diverse possible applications, such as in gas storage and separation, catalysis, luminescent sensing, and optoelectronic devices. 10–12,16,18–23 HOFs are assembled from organic units through intermolecular hydrogen (H) bonding interactions, and the resulting frameworks can be further strengthened via other interactions, such as π–π stacking, van der Waals, dipole–dipole and/or C–H–π interactions. 11,12,17,24,25 The inherent features of H-bond interactions, such as reversibility and directionality, endow these materials with unique properties, including crystallinity, flexibility, structural diversity, and easy recovery via recrystallization.…”

“…These photoinduced reactions lead to significant changes in the luminescence properties, prompting the search for new HOFs for specific applications. 10–12,16,18–23 Also, HOFs can serve as a host for guest molecules (drugs, ions, chromophores) with specific capabilities. This multifunctionality expands the potential applications of HOFs in a wide variety of fields, not limited to photonics, such as sensing, catalysis, and drug delivery.…”