RESUMEN
Recent progress in synthesizing and integrating surface-supported metal-organic frameworks (SURMOFs) has highlighted their potential in developing hybrid electronic devices with exceptional mechanical flexibility, film processability, and cost-effectiveness. However, the low electrical conductivity of SURMOFs has limited their use in devices. To address this, researchers have utilized the porosity of SURMOFs to enhance electrical conductivity by incorporating conductive materials. This study introduces a method to improve the electrical conductivity of HKUST-1 templates by in situ polymerization of conductive polypyrrole (PPy) chains within the SURMOF pores (named as PPy@HKUST-1). Nanomembrane-origami technology is employed for integration, allowing a rolled-up metallic nanomembrane to contact the HKUST-1 films without causing damage. After a 24 h loading period, the electrical conductivity at room temperature reaches approximately 5.10-6 S m-1 . The nanomembrane-based contact enables reliable electrical characterization even at low temperatures. Key parameters of PPy@HKUST-1 films, such as trap barrier height, dielectric constant, and tunneling barrier height, are determined using established conduction mechanisms. These findings represent a significant advancement in real-time control of SURMOF conductivity, opening pathways for innovative electronic-optoelectronic device development. This study demonstrates the potential of SURMOFs to revolutionize hybrid electronic devices by enhancing electrical conductivity through intelligent integration strategies.
RESUMEN
Surface-Mounted Metal-Organic Frameworks (SURMOFs) are promising materials with a wide range of applications and increasing interest in different technological fields. The use of SURMOFs as both the active and passive tail in electronic devices is one of the most exciting possibilities for such a hybrid material. In such a context, the adhesion, roughness, and crystallinity control of SURMOF thin films are challenging and have limited their application in new functional electronic devices. Self-assembled monolayers (SAMs), which ensure the effective attachment of the SURMOF onto substrates, also play a critical role that can profoundly affect the SURMOF growth mechanism. Herein, we demonstrate that the deterministic control of the SAM chain length influences the preferential orientation of SURMOF films. As the SAM chain length increases, HKUST-1 thin films tend to change their preferential orientation from the [111] towards the [100] direction. Such control can be achieved on both electrically conducting and insulating substrates, opening the possibility of having the very same preferential crystalline orientation on surfaces of different nature, which is of fundamental importance for SURMOF-based functional electronic devices.