An amine functionalized zirconium metal–organic framework as an effective chemiresistive sensor for acidic gases

Abstract

Pore surface functionalization of a metal–organic framework (MOF) with an amine moiety has turned an innocent MOF into a chemiresistive sensor for acidic gases.

Metal-Organic Frameworks for Chemiresistive Sensors

“…2E). 40 The high acidity of SO 2 enables a charge transfer coupling with amine groups in the organic ligands of MOFs, thus leading to the resistance decrease (jDR/R 0 j = 21.6% to 10 ppm of SO 2 ) of NH 2 -UiO-66 (band gap = 2.75 eV) 41 upon SO 2 adsorption (Figure 2F). Although these works demonstrated the feasibility of MOF-based chemiresistive sensors, there were some limitations:…”

“…7 Although the integration of MOFs with conductive materials having high chemical stability enabled the detection of NH 3 gas at room temperature in air, 43 they exhibited poor sensing properties. Therefore, to address the inherent issues in pure MOFs, highly conductive MOFs with high chemical stability and MOF derivatives, including carbon composites Reprinted with permission from Chen et al 36 Copyright 2014 American Chemical Society, Chen et al, 39 Copyright 2014 American Chemical Society, and DMello et al 40 Copyright 2019 Royal Society of Chemistry.…”

Quantification of the mixed-valence and intervalence charge transfer properties of a cofacial metal–organic framework via single crystal electronic absorption spectroscopy

“…1,2 The ability to engineer MOF materials with intrinsic charge transfer properties is attractive for many applications that harness electron transfer, such as conductivity, [3][4][5][6] electrocatalysis, 7-10 magnetism 5,[11][12][13][14] and chemiresistive sensing. [15][16][17][18] Despite this, long-range charge delocalisation in 3D materials has proven difficult to achieve, oen due to the intrinsically insulating nature of the organic components, the closed-shell nature of the metal ions (i.e. Zn(II), Cd(II), Zr(IV)) and structural instability triggered by the oxidation or reduction of the structural components.…”

A dual functional 1D Cd‐based coordination polymer for the highly luminescent sensitive detection of Fe3+ and picric acid

“…[1,2] In recent years, CPs and MOFs have been applied in a versatile way in gas adsorption and separation, [3,4] catalysis, [5,6] magnetics, [7,8] bioimaging [9] and drug delivery. [10] Now, on account of their outstanding modifiability and excellent optical properties, great progress has been made in sensing nitro compounds, [11,12] metal cations, [13] small gas molecules, [14,15] pH [16] and temperature. [17,18] With the rapid development of industrialization and increasing environmental pollution, there is an increasing need for highly selective detection of organic pollutants and heavy metal ions, especially Fe 3+ ions.…”

“…[ 1,2 ] In recent years, CPs and MOFs have been applied in a versatile way in gas adsorption and separation, [ 3,4 ] catalysis, [ 5,6 ] magnetics, [ 7,8 ] bioimaging [ 9 ] and drug delivery. [ 10 ] Now, on account of their outstanding modifiability and excellent optical properties, great progress has been made in sensing nitro compounds, [ 11,12 ] metal cations, [ 13 ] small gas molecules, [ 14,15 ] pH [ 16 ] and temperature. [ 17,18 ]…”