Direct in Situ Conversion of Metals into Metal–Organic Frameworks: A Strategy for the Rapid Growth of MOF Films on Metal Substrates

Abstract

The fabrication of metal-organic framework (MOF) films on conducting substrates has demonstrated great potential in applications such as electronic conduction and sensing. For these applications, direct contact of the film to the conducting substrate without a self-assembled monolayer (SAM) is a desired step that must be achieved prior to the use of MOF films. In this report, we propose an in situ strategy for the rapid one-step conversion of Cu metal into HKUST-1 films on conducting Cu substrates. The Cu substrate acts both as a conducting substrate and a source of Cu ions during the synthesis of HKUST-1. This synthesis is possible because of the simultaneous reaction of an oxidizing agent and a deprotonating agent, in which the former agent dissolves the metal substrate to form Cu ions while the latter agent deprotonates the ligand. Using this strategy, the HKUST-1 film could not only be rapidly synthesized within 5 min but also be directly attached to the Cu substrate. Based on microscopic studies, we propose a plausible mechanism for the growth reaction. Furthermore, we show the versatility of this in situ conversion methodology, applying it to ZIF-8, which comprises Zn ions and imidazole-based ligands. Using an I-filled HKUST-1 film, we further demonstrate that the direct contact of the MOF film to the conducting substrate makes the material more suitable for use as a sensor or electronic conductor.

Pristine Transition‐Metal‐Based Metal‐Organic Frameworks for Electrocatalysis

“…[111] There have been many reported methods to fabricate MOF coatings, such as Langmuir-Blodgett (LB) method, [112] gas-phase deposition, [113] electrochemical preparation methods, [114] direct conversion from metals, [115] etc. Thus, the accurate and sensitive glucose detection is of great importance.…”

Metal–Organic Frameworks Derived from Zero‐Valent Metal Substrates: Mechanisms of Formation and Modulation of Properties

“…However, the successful construction of MOFs film can only be achieved by (i) the coaddition of soluble metal salts into the synthesis solution together with metal substrate (HKUST-1, [7] MIL-53 (Al) [23] ), (ii) forming metal oxides overlayer on metal substrate via a preceding oxidation step (Zn 3 (BTC) 2 [24] ), or (iii) adding oxidation reagents in the synthesis solution in order to oxidize metal surface (HKUST-1, ZIF-8 [25] ). However, the successful construction of MOFs film can only be achieved by (i) the coaddition of soluble metal salts into the synthesis solution together with metal substrate (HKUST-1, [7] MIL-53 (Al) [23] ), (ii) forming metal oxides overlayer on metal substrate via a preceding oxidation step (Zn 3 (BTC) 2 [24] ), or (iii) adding oxidation reagents in the synthesis solution in order to oxidize metal surface (HKUST-1, ZIF-8 [25] ).…”

Surface modification of α‐zirconium phosphate by zeolitic imidazolate frameworks‐8 and its effect on improving the fire safety of polyurethane elastomer

“…Metal organic frameworks (MOFs), as a new porous material, are formed by self‐assembly of organic ligands and metal ions . Because of its many advantages, such as large specific surface area, high porosity, adjustable pore size, and size, MOFs have attracted much attention in gas storage and separation .…”

“…11,12 Metal organic frameworks (MOFs), as a new porous material, are formed by self-assembly of organic ligands and metal ions. 13,14 Because of its many advantages, such as large specific surface area, high porosity, adjustable pore size, and size, MOFs have attracted much attention in gas storage and separation. [15][16][17][18][19][20][21] Recently, researchers have used MOF materials in the field of flame retardancy and studied the flame retardancy effect of different MOF materials on polymers.…”