Defect Engineering To Tailor Metal Vacancies in 2D Conductive Metal–Organic Frameworks: An Example in Electrochemical Sensing

Abstract

Two-dimensional conductive metal–organic frameworks (2D conductive MOFs) with π–d conjugations exhibit high electrical conductivity and diverse coordination structures, making them constitute a desirable platform for new electronic devices. Defects are inevitable in the self-assembly process of 2D conductive MOFs. Arguably, defect engineering that deliberately manipulates defects demonstrates great potential to enhance the electrocatalytic activity of this family of novel materials. Herein, a facile and universal defect engineering strategy is proposed and demonstrated for metal vacancy regulation of metal benzenehexathiolato (BHT) coordination polymer films. Controllable metal vacancies can be produced by simply tuning the proton concentration during the confined self-assembly process at the liquid–liquid interface. This facile but universal defect design strategy has been proven to be effective in a class of materials including Cu-BHT, Ni-BHT, and Ag-BHT for physicochemical regulation. To further demonstrate the feasibility and practicality in electrochemical applications, the elaborately fabricated Cu-BHT films with abundant Cu vacancies deliver competitive performance in electrocatalytic sensing of H2O2. Mechanistic analysis revealed that the Cu vacancies act as effective active sites for adsorption and reduction of H2O2, and the tuned electronic structure boosts the electrocatalytic reaction. The developed advanced sensing platform confirms the excellent commercial potential of Cu-BHT sensors for H2O2. The findings provide insights into the molecular structure design of 2D conducting MOFs by defect engineering and demonstrate the commercial potential of Cu-BHT electrochemical sensors.

The Recent Development of Two‐dimensional Conjugated Coordination Polymers

“…Furthermore, Paul K. Chu et al proposed a facile and universal defect engineering strategy for the metal vacancy regulation of Cu 3 BHT. [40] By adjusting the proton concentration during the confined self-assembly process at the liquid-liquid interface, it is possible to create metal vacancies. The existence of Cu vacancies can result in structural imperfections, leading to a decrease in both the crystallinity and electrical conductivity of Cu 3 BHT.…”

“…Furthermore, Paul K. Chu et al. proposed a facile and universal defect engineering strategy for the metal vacancy regulation of Cu 3 BHT [40] . By adjusting the proton concentration during the confined self‐assembly process at the liquid‐liquid interface, it is possible to create metal vacancies.…”

Paper Sensor Modified with MoS2 for Detection of Dopamine Using a Machine-Intelligent Web App Interface

“…Thus, in recent years, research has shifted toward the development of simple, low-cost point-of-care diagnostic devices that can provide an immediate response to the user in the hour of need. The electrochemical biosensors fulfill these criteria and have become a standard option in the scientific community due to their low cost, high sensitivity, good specificity, low response time, and compatibility with integrated circuit technology for easy readout. − Herein, DA being an easily oxidized electroactive molecule and having an oxidation potential in the potential window of several electrodes, the electrochemical method is presumed to be an innate choice for DA detection. − …”

Homogeneous voltammetric sensing strategy for lead ions based on aptamer gated methylthionine chloride@UiO-66-NH2 framework as smart target-stimulated responsive nanomaterial

“…[32][33][34] On the other hand, metal-organic frameworks (MOFs) are a broad class of inorganic/organic crystalline porous nanomaterials with high porosity, high surface area, multiple functionalities and adjustable pore size. [35][36][37][38][39] These interesting characteristics enable MOFs as an ideal smart material substrate in chemo/biosensing. 40,41 UiO-66-NH 2 , a hierarchically porous zirconium-based MOF nanomaterial, has large specific area, stable porous structure and high porosity, [42][43][44][45] these interesting properties make it well suited as a nanocarrier to encapsulate an electroactive signal probe.…”

“…32–34 On the other hand, metal–organic frameworks (MOFs) are a broad class of inorganic/organic crystalline porous nanomaterials with high porosity, high surface area, multiple functionalities and adjustable pore size. 35–39 These interesting characteristics enable MOFs as an ideal smart material substrate in chemo/biosensing. 40,41…”