SEMINAIRE COMMUN LMGP - 07.09.2021 - Dr. Joao RESENDE et M. Emanuel CARLOS

Dr. Joao RESENDE
Alma Science Colab, Caparica Portugal

AlmaScience aims to deliver ecologically sustainable and universally accessible solutions by effectively enabling IoT in areas like: security, environment, health, brand protection, electronics, logistics, food or marketing. These goals are being developed through the exploitation of nanotechnology and advanced functional materials and their use to create ecological game-changing paper-based, fully printable, multifunctional devices and systems.

In the case of cellulose-based composites, we aim to create low-cost, lightweight and biodegradable materials that will be essential for sustainable technologies, such as smart packaging and water filtering systems. In the collaboration between AlmaScience and LMGP, we plan to deposit Metal-Oxides and Metal-Organic Frameworks (MOFs) coatings on cellulose-based substrates using an Atmospheric Pressure Spatial Atomic Layer Deposition (AP-SALD) system. The development of composites that combine oxides and cellulose fibers will create protective coatings in a nanostructured cellulose paper to enhance the barrier properties for water and gases transport. Furthermore, we plan to growth MOFs on cellulose membranes to enhance the filter properties for water purification, to remove pollutants as heavy metals.

“Design and Synthesis of Printed Metal Oxides Devices”

Emanuel CARLOS, Post-doc,
i3N/CENIMAT, Department of Materials Science, Faculty of Sciences and Technology, Universidade NOVA de Lisboa and CEMOP/UNINOVA, Caparica



Abstract

Flexible electronics have open new windows to develop low-cost and large-area manufacturing, serving a plethora of sectors, namely, Internet of things (IoT) and cloud requirements. From there emerged the necessity of printing energy efficient eco-devices using low-temperature methods in the production and processing of nanomaterials, thus reducing the human carbon footprint. Solution-based metal oxide devices answer to this demand, however, the production of these materials usually requires higher temperatures and longer annealing times which restrict their use on flexible substrates as well as negatively impact the environment and energy efficiency. Nevertheless, to achieve the same performance at low temperature than physical methods, solution combustion synthesis (SCS) and photonic curing post-deposition treatment have been essential. The combination of these methods improves the reliability of the nanoscale film morphology, composition of metal oxides and stability over time. Also, the current main deposition method is spin-coating being a critical setback for their individualization and upscale to the printing industry.

In this work, we overview some fundamental parameters in the solution synthesis of metal oxides to guarantee the best molecular-level mixing of reactants on an aqueous or solvent-based solution some parameters need to be fulfilled, such as fuel type, metal cations precursors, stoichiometry ratio (ɸ), pH effect, atmosphere and initiation type. A special attention is given to the requirements to transfer these inks from lab (spin-coating) to large-scale manufacturing and their application in memristors, diodes and TFTs.