Large-area synthesis of nanoscopic catalyst-decorated conductive MOF film using microfluidic-based solution shearing

Abstract

Conductive metal-organic framework (C-MOF) thin-films have a wide variety of potential applications in the field of electronics, sensors, and energy devices. The immobilization of various functional species within the pores of C-MOFs can further improve the performance and extend the potential applications of C-MOFs thin films. However, developing facile and scalable synthesis of high quality ultra-thin C-MOFs while simultaneously immobilizing functional species within the MOF pores remains challenging. Here, we develop microfluidic channel-embedded solution-shearing (MiCS) for ultra-fast (≤5 mm/s) and large-area synthesis of high quality nanocatalyst-embedded C-MOF thin films with thickness controllability down to tens of nanometers. The MiCS method synthesizes nanoscopic catalyst-embedded C-MOF particles within the microfluidic channels, and simultaneously grows catalyst-embedded C-MOF thin-film uniformly over a large area using solution shearing. The thin film displays high nitrogen dioxide (NO2) sensing properties at room temperature in air amongst two-dimensional materials, owing to the high surface area and porosity of the ultra-thin C-MOFs, and the catalytic activity of the nanoscopic catalysts embedded in the C-MOFs. Therefore, our method, i.e. MiCS, can provide an efficient way to fabricate highly active and conductive porous materials for various applications.

Room-Temperature Mixed-Potential Type ppb-Level NO Sensors Based on K2Fe4O7 Electrolyte and Ni/Fe–MOF Sensing Electrodes

“…It is formed by the self-assembly of metal ions/ion clusters and organic ligands with a facile synthesis route. Unsaturated coordination metal nodes and surface defects endow MOF materials with good catalytic activity. − On selection of metal ion nodes, transition metals were employed in this work because of their reported excellent catalytic activity toward NO electrochemical reaction. , Thus, Ni/Fe–MOFs with porous structure and good electrocatalytic activity were determined as the SE materials.…”

Recent Progress of Electric Conductive Metal-Organic Frameworks Thin Film

“…"Face-to-Face confinement" 方法的成功之处在于利用了毛细管现象, 首先 在两个功能化基底构建的微孔界面得到低成核密度的 Cu 2 ＋ , 从而有利于薄膜的生长. 还有, Kim 等 [22] 为了将 功能性纳米颗粒嵌入 EC-MOF 中以拓展材料的应用, 提 出了一种新型的基于微流控的溶液剪切技术, 合成了负 载催化剂的高质量 EC-MOF 薄膜 Pt@Cu 3 (HHTP) 2 [72] . 相比于传统的固态合成技术, 该方法制备的铂纳米颗粒 尺寸只有 2 nm 左右, 并且均匀分散在厚度约 25 nm 的 Cu…”

Metal-Organic-Frameworks: Low Temperature Gas Sensing and Air Quality Monitoring

“…A combination of colorimetric and chemoresistive MOF detectors (MOF A, with Co and octadentate calix [4]-resorcinarene as the metallic centre and ligand, respectively) was synthesised by Ma et al [90] using a solvothermal approach. The sensing mechanism was based on the absorption of NO 2 gas molecules onto the surface of MOF A.…”

“…Recently, a novel microfluidic channel-embedded solution-shearing (MiCS) fabrication scheme was proposed for the large-area synthesis of MOF-based thin films (tens of nanometres) for the room temperature detection of NO 2 gas molecules [90]. Here, similar to the blade-coating technique, a solution-to-solid transition close to the edge of the meniscus was formed between a moving blade and a heated substrate resulted in the deposition of a thin film on the substrate [123].…”