Related Experiment Video
Updated: May 6, 2026

IridiumIII Luminescent Probe for Detection of the Malarial Protein Biomarker Histidine Rich Protein-II
Published on: July 7, 2015
Luminescent Metal-Organic Framework with Outstanding "Turn-On" Hg2+ Sensing Ability First Constructed by an AIE
Jinfang Zhang1, Xingyu Tao1, Yinlong Yue1
1International Joint Research Center for Photoresponsive Molecules and Materials, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, P. R. China.
Abstract:
Hg2+ is highly toxic and can cause serious harm to the environment and humans. Thus, it is vital to develop efficient Hg2+ sensors. In this work, a LMOF-based (LMOF = luminescent metal-organic framework) "turn-on" Hg2+ sensor (1) is first developed by an aggregation-induced emission (AIE) functional ligand. 1 with a formula of [Cd3(L)2(NDA)3(H2O)2·(L)(MeOH)] (L = 4,4'-((2,7-di-tert-butyl-9H-fluoren-9-ylidene)-methylene)dipyridine; H2NDA = 1,4-naphthalenedicarboxylic acid) exhibits a unique (3,4)-connected 2-D framework with 3-connected Cd1, 4-connected [Cd2(COO)3]+ cluster, and L and NDA2- bridges. The fluorene rings of L in 1 stack in a back-to-back manner. 1 has excellent water, pH, and thermal stabilities and can "turn-on" detect Hg2+ with ultrahigh sensitivity, good selectivity, and recyclability in a water medium. Furthermore, 1 shows obvious naked-eye-visible emission change and an extremely fast sensing response toward Hg2+ (<1 S) and can maintain its enhanced intensity over 5 min. The test paper is developed for practical "turn-on" Hg2+ sensing application. The "turn-on" Hg2+ sensing mechanism of 1 is discussed in detail.
Related Concept Videos
Metal-Ligand Bonds
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
Valence Bond Theory
Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
Colors and Magnetism
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
Photoluminescence: Applications

