Energy Transfer in Metal–Organic Frameworks for Fluorescence Sensing

Abstract

The development of materials with outstanding performance for sensitive and selective detection of multiple analytes is essential for the development of human health and society. Luminescent metal–organic frameworks (LMOFs) have controllable surface and pore sizes and excellent optical properties. Therefore, a variety of LMOF-based sensors with diverse detection functions can be easily designed and applied. Furthermore, the introduction of energy transfer (ET) into LMOFs (ET-LMOFs) could provide a richer design concept and a much more sensitive and accurate sensing performance. In this review, we focus on the recent five years of advances in ET-LMOF-based sensing materials, with an emphasis on photochemical and photophysical mechanisms. We discuss in detail possible energy transfer processes within a MOF structure or between MOFs and guest materials. Finally, the possible sensing applications of the ET-LMOF-based sensors are highlighted.

RhB-Embedded Zirconium–Biquinoline-Based MOF Composite for Highly Sensitive Probing Cr(VI) and Photochemical Removal of CrO42–, Cr2O72–, and MO

“…Otherwise, it is also possible for MOFs to achieve luminescence properties in the form of ligand-to-metal charge transfer (LMCT) or metal-to-ligand charge transfer (MLCT). 36,37 Here, as proved in Figure 3a, for the sole zirconium−biquinoline-based MOF, the shape and position of its emission peak at 427 nm are very similar to that of the luminous signal of the free H 2 L ligand located around 452 nm. This indicates that the fluorescence emission ability of the framework should be inherited from the luminescence talent of organic units.…”

Interface Engineering of Bi‐Fluorescence Molecules for High‐Performance Data Encryption and Ultralow UV‐Light Detection

“…Organic emitters with the dynamic ability to tune emission colors from different excited states in response to external stimuli, such as optical excitation, mechanical force, and pressure exhibit high potential in life science, energy conversion, and safety engineering. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] However, it is extremely difficult, selectively excited (Figure 1b). By varying the excitation energies from 4.27 eV (290 nm) to 3.44 eV (360 nm), the emission color of the OA-DFBK composites was deterministically tuned from deep blue to green in the spectral range.…”

“…Organic emitters with the dynamic ability to tune emission colors from different excited states in response to external stimuli, such as optical excitation, mechanical force, and pressure exhibit high potential in life science, energy conversion, and safety engineering. [ 1–16 ] However, it is extremely difficult, if not impossible, to achieve such a tunability due to the difficulty in separating large energies and the stability of different electronic excited states. [ 17–21 ] Therefore, it remains a challenge to precisely control the luminescence of organic chromophores from different electronically‐excited states.…”

A water-stable Zn4O-based MOF decorated with carbazolyl chromophores for multi-responsive fluorescence sensing of Fe3+, Cr2O72− and nitro-compounds

“…In the past decade, fluorescent sensors based on metalorganic frameworks (MOFs) have attracted much attention due to their adjustable porosity, ligand modifiability, high sensitivity and fast response time. [23][24][25] Zinc(II), as a kind of d 10 metal ion, often was used for constructing luminescent MOFs due to its abundance, cheapness and environmental friendliness. Several Zn-based luminescent MOFs have been reported to demonstrate the ability to sense various analytes including metal cations, anions and small organic molecules including nitroaromatics.…”