Coating of Conducting and Insulating Threads with Porous MOF Particles through Langmuir-Blodgett Technique.

Sakandar Rauf,Khaled N Salama,Olivier Roubeau,Mohamed Eddaoudi,Christian Serre,Miguel A Andrés,Ignacio Gascón

doi:10.3390/nano11010160

Abstract

The Langmuir-Blodgett (LB) method is a well-known deposition technique for the fabrication of ordered monolayer and multilayer thin films of nanomaterials onto different substrates that plays a critical role in the development of functional devices for various applications. This paper describes detailed studies about the best coating configuration for nanoparticles of a porous metal-organic framework (MOF) onto both insulating or conductive threads and nylon fiber. We design and fabricate customized polymethylmethacrylate sheets (PMMA) holders to deposit MOF layers onto the threads or fiber using the LB technique. Two different orientations, namely, horizontal and vertical, are used to deposit MIL-96(Al) monolayer films onto five different types of threads and nylon fiber. These studies show that LB film formation strongly depends on deposition orientation and the type of threads or fiber. Among all the samples tested, cotton thread and nylon fiber with vertical deposition show more homogenous monolayer coverage. In the case of conductive threads, the MOF particles tend to aggregate between the conductive thread’s fibers instead of forming a continuous monolayer coating. Our results show a significant contribution in terms of MOF monolayer deposition onto single fiber and threads that will contribute to the fabrication of single fiber or thread-based devices in the future.

Highlights

In the case of horizontal deposition, the fiber or threads were mounted onto the frame in the horizontal direction, and in the case of vertical deposition, the nylon fiber or threads were placed in a vertical direction in reference to the water surface where the metal-organic framework (MOF) dense monolayer was previously formed
The deposition process we report does not require any special pre-treatment of the samples and is reproducible, either for the nylon fiber or various threads of each deposition batch or from deposition batch to deposition batch
It has been demonstrated that the chemical nature, surface roughness, and type of fiber or thread, either single-fiber or bundles, as well as deposition orientation all appear to influence the ability to obtain a monolayer coating of MOF particles

Summary

Introduction

The interest of the scientific community in the preparation, characterization, and study of metal-organic frameworks (MOFs) has continuously grown during the last forty years [1,2,3]. MOFs possess exceptional chemical versatility and tunable porosity that make them promising materials for a wide range of applications [4], including, among others, separation science [5,6,7,8], health [9,10,11], and the environment [12]. The deposition of MOF thin coatings onto the surface of textiles is a challenging target that has been scarcely explored. Previous studies have shown that it is possible to integrate MOF and fabrics and the use of mixed

Methods

Results

Conclusion