Construction of Free-Standing MOF Sheets through Electrochemical Printing on Superhydrophobic Substrates
Yupeng Chen, Zhongpeng Zhu, Xiangyu Jiang, Lei Jiang
Abstract
Metal–organic framework (MOF) membranes have significant application prospects in different fields, such as separation, detection, anticorrosion and energy capture and conversion and so on. However, the difficulty of constructing free-standing MOF membranes has hindered their applications. Here, we propose a facile strategy to fabricate free-standing MOF sheets with easy-peeling and easy-transfer properties through electrochemical printing on superhydrophobic micropillar-structured substrates. During the electrochemical printing process, electrophoretic deposition will occur along the solid/liquid/gas triphase interface on these substrates. First, the effects of the electrophoretic deposition conditions, such as deposition time and current, on the thickness-controlled growth on superhydrophobic substrates are explored. Then, the influences of the geometric parameters, such as diameter and distance, and wettability of the micropillars on constructing free-standing MOF sheets are systematically studied. Furthermore, the MOF sheets exhibit the properties of capillarity-assisted peeling from superhydrophobic substrates and spreading-assisted transfer to superhydrophilic substrates, followed by the demonstration of the generality. Therefore, it is a facile method to prepare free-standing MOF sheets with easy-peeling and easy-transfer properties taking advantage of electrochemical printing on superhydrophobic substrates, giving impetus to the improvement of the productivity and the corresponding applications in various fields.