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In this work, we develop processing techniques for the development and fabrication of spray deposited CNT based devices. After developing a sprayable CNT ink, we introduce a spray deposition process with according characterization. Next, we present the development and characterization of CNT TFTs, followed by the coupling with IGZO transistors to fabricate functional flexible logic gates. Finally, we present a process for the fabrication and characterization of resistive CNT based gas sensors, additionally coupling this with the TFT technology to fabricate chemFETs. In dieser Arbeit entwickeln wir Verarbeitungstechniken für die Entwicklung und Herstellung von sprühbeschichteten CNT-basierten Bauteilen. Nach der Entwicklung einer sprühfähigen CNT-Tinte führen wir einen Sprühabscheidungsprozess mit entsprechender Charakterisierung ein. Als nächstes präsentieren wir die Entwicklung und Charakterisierung von CNT-TFTs, gefolgt von der Kopplung mit IGZO-Transistoren, um funktionale flexible Logikgatter herzustellen. Schließlich stellen wir ein Verfahren zur Herstellung von resistiven CNT-basierten Gassensoren vor, das zusätzlich mit der TFT-Technologie zur Herstellung von chemFETs gekoppelt wird.

In this article, we report on an efficient post-treatment protocol for the manufacturing of pristine single-walled carbon nanotube (SWCNT) films. To produce an ink for the deposition, the SWCNTs are dispersed in an aqueous solution with the aid of a carboxymethyl cellulose (CMC) derivative as the dispersing agent. On the basis of this SWCNT-ink, ultra-thin and uniform films are then fabricated by spray-deposition using a commercial and fully automated robot. By means of X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM), we show that the CMC matrix covering the CNTs can be fully removed by an immersion treatment in HNO3 followed by thermal annealing at a moderate temperature of 100 ºC, in the ambient air. We propose that the presented protocols for the ink preparation and the post-deposition treatments can in future serve as a facile and efficient platform for the fabrication of high-quality and residual-free SWCNT films. The purity of SWCNT films is of particular importance for sensing applications, where residual-induced doping and dedoping processes distort the contributions from the sensing specimen. To study the usability of the presented films for practical applications, gas sensors are fabricated and characterized with the CNT-films as the sensing material, screen printed silver-based films for the interdigitated electrode (IDE) structure, and polyimide as a flexible and robust substrate. The sensors show a high and stable response of 11% to an ammonia (NH3) test gas, at a concentration of 10 ppm., The authors thank the Deutsche Forschungsgemeinschaft (DFG) and the Natural Sciences and Engineering Research Council (NSERC) for financial support of the Alberta/Technische Universität München Graduate School for Functional Hybrid Materials ATUMS (IRTG2022, NSERC CREATE), as well as the TUM Graduate School, the Nanosystems Initiative Munich (NIM), and the TUM International Graduate School of Science and Engineering (IGSSE).

We have synthesized a novel three-dimensional metal-organic-framework (MOF) based on the perylene-3,4,9,10-tetracarboxylate linker and potassium as metallic centre. We report the formation of this K-based MOF using conventional routes with water as solvent. This material displays intense green photoluminescence at room temperature, and displays an aggregation dependent quenching. Correlation of the optical properties with the crystalline packing was confirmed by DFT calculations. We also demonstrate its potential to build humidity actuators with a reversible and reproducible response, with a change of 5 orders of magnitudes in its impedance at about 40% relative humidity (RH). This 3D-MOF is based on an interesting perylene derivative octadentate ligand, a moiety with interesting fluorescent properties and known component in organic semiconductors. To the best of our knowledge, this is the first time to build such a printed and flexible actuator towards humidity with a reversible response, enabling precise humidity threshold monitoring. This work was supported by the Junta de Andalucia (FQM-1484, and FQM-195). Red Guipuzcoana de Ciencia, Tecnologia e Innovacion (OF188/2017) and University of the Basque Country (GIU14/01, EHUA16/32). BB acknowledges funding by RyC-2012-10381 contract and computational resources provided by the RES and Alhambra supercomputing facilities. This work was also supported by the German Research Foundation (DFG) and the Technical University of Munich within the Open Access Publishing Funding Programme.