Recent Advances in Printed Capacitive Sensors

In this review paper, we summarize the latest advances in the field of capacitive sensors fabricated by printing techniques. We first explain the main technologies used in printed electronics, pointing out their features and uses, and discuss their advantages and drawbacks. Then, we review the main types of capacitive sensors manufactured with different materials and techniques from physical to chemical detection, detailing the main substrates and additives utilized, as well as the measured ranges. The paper concludes with a short notice on status and perspectives in the field.H2020-MSCA-IF-2017-794885-SELFSEN

Highly Sensitive Soft Foam Sensors for Wearable Applications

Due to people’s increasing desire for body health monitoring, the needs of knowing humans’ body parameters and transferring them to analyzable and understandable signals become increasingly attractive and significant. The present body-sign measurement devices are still bulky medical devices used in settings such as clinics or hospitals, which are accurate, but expensive and cannot achieve the personalization of usage targets and the monitoring of real-time body parameters. Many commercial wearable devices can provide some of the body indexes, such as the smartwatch providing the pulse/heartbeat information, but cannot give accurate and reliable data, and the data could be influenced by the user’s movement and the loose wearing habit, either. In this way, developing next-generation wearable devices combining good wearable experience and accuracy is gathering increasing attention. The aim of this study is to develop a high-performance pressure/strain sensor with the requirements of comfortable to wear, and having great electromechanical behaviour to convert the physiological signal to an analyzable signal

Multifunctional photocurable advanced materials for electronics and sensing applications

276 p.Photocurable multifunctional polymer composites have been obtained and characterized according totheir photopolymerization capability, physico-chemical and functional properties. Polyurethane acrylate(PUA) has been selected as polymer matrix combined with multi-walled carbon nanotubes (MWCNT),barium titante (BaTiO3), indium tin oxide (ITO), magnetite (Fe3O4), cobalt ferrite (CFO), neodymiumiron boron alloy (NdFeB) and 1-buthyl-3-methylimidazolium tetracholonickelate ([Bmim]2NiCl4) ionicliquid (IL) to obtain different functional and multifunctional responses.Different functional and multifunctional responses have been added to the UV curable polymer,depending on the filler type and content. The inclusion of MWCNTs induce a piezoresistive responsecharacterized by GF values between 0.8 and 2.6. BaTiO3 and ITO, strongly increase the dielectricconstant from 7.5 to 25 and up to 33, respectively. In the case of Fe3O4, CFO and NdFeB, magneticcomposites with tailored magnetic properties (from hard to soft magnetic ones) are obtained. Saturationmagnetization values up to 63.86 emu/g, remanence up to 44.95 emu/g and coercivity up to 7000 Oe havebeen obtained depending on filler type and content. Finally, IL allows the preparation of temperatureactivated thermochromic humidity sensing materials with a colour change from blue to colourless,depending on relative humidity.Thus, this work successfully demonstrated the development of UV photocurable functional andmultifunctional materials, compatible with printing technologies, for electronic and sensing applications.BcMaterials: Basque Center for materials applications & nanostructure

Multifunctional photocurable advanced materials for electronics and sensing applications

276 p.Photocurable multifunctional polymer composites have been obtained and characterized according totheir photopolymerization capability, physico-chemical and functional properties. Polyurethane acrylate(PUA) has been selected as polymer matrix combined with multi-walled carbon nanotubes (MWCNT),barium titante (BaTiO3), indium tin oxide (ITO), magnetite (Fe3O4), cobalt ferrite (CFO), neodymiumiron boron alloy (NdFeB) and 1-buthyl-3-methylimidazolium tetracholonickelate ([Bmim]2NiCl4) ionicliquid (IL) to obtain different functional and multifunctional responses.Different functional and multifunctional responses have been added to the UV curable polymer,depending on the filler type and content. The inclusion of MWCNTs induce a piezoresistive responsecharacterized by GF values between 0.8 and 2.6. BaTiO3 and ITO, strongly increase the dielectricconstant from 7.5 to 25 and up to 33, respectively. In the case of Fe3O4, CFO and NdFeB, magneticcomposites with tailored magnetic properties (from hard to soft magnetic ones) are obtained. Saturationmagnetization values up to 63.86 emu/g, remanence up to 44.95 emu/g and coercivity up to 7000 Oe havebeen obtained depending on filler type and content. Finally, IL allows the preparation of temperatureactivated thermochromic humidity sensing materials with a colour change from blue to colourless,depending on relative humidity.Thus, this work successfully demonstrated the development of UV photocurable functional andmultifunctional materials, compatible with printing technologies, for electronic and sensing applications.BcMaterials: Basque Center for materials applications & nanostructure