Vilarinho Research Group is engaged in fundamental and applied research in the synthesis, properties and processing of functional materials for electronics, microelectronics and related applications.
Vilarinho Research Group has been mainly focused on electrical polarization phenomena in solids, aiming to understand mechanisms that control electrical polarization at the macroscopic and nanoscale level, and applying such understanding to the development of advanced nano and microelectronic devices. For that her group has been using electrical and structural characterization tools (impedance spectroscopy, piezo- ferroelectric analysis, scanning probe microscopy, electron microscopy, Raman spectroscopy, among others) at the highest level. Materials under investigation include perovskite type ferroelectric, piezoelectric, dielectric and multiferroic oxides and piezoelectric polymers (PLLA and PVDF). Applications of these materials include microelectronic devices as memories, sensor and actuators, energy harvesters, thermoelectric devices, tunable dielectrics, but also and more recently biorelated uses, as bio-compatible piezoelectric platforms for tissue growth, biosensors, among others.
While understanding materials properties is central in many of her R&D activities, the synthesis of nanofunctional materials in different geometries (1D, 2D and 3D) at low temperatures for compatible materials integration and using low cost approaches is becoming increasingly important in the group’s research activities. Within this context the group has been exploiting hydrothermal synthesis, diphasic sol precursors, photo chemical solution and electrophoretic deposition (EPD) for the preparation of nanoparticulates, nanocomposites, thin and thick films of functional materials.
Complying with The European Green Deal and to contribute to a modern, resource-efficient and competitive economy where there are no net emissions of greenhouse gases and where economic growth is decoupled from resource use, Vilarinho group initiated recently the exploitation of low-temperature budget processes, as FLASH sintering, a new method to densify materials abruptly above a threshold condition by a combination of furnace-temperature and DC electrical field directly applied to the specimen and Cold Sintering, using water as a transient solvent to effect densification at temperatures between room temperature and 200 ºC.
In addition, one of the newest interests of Vilarinho group is related with Additive Manufacturing (AM) of ceramic, conductors and composite materials. The aim is on one side to explore techniques as 3D Printing and Robocasting for the fabrication of ceramics and composites and on the other hand to explore Robocasting of functional ceramics and conductors materials for microelectronics, in direct collaboration with Portuguese Companies (Costa Verde SA, Simoldes) and Recipneus).
The current research interests of the group comprise the following topics / projects: (1) Lead Free Ferroelectrics / Piezoelectrics, (2) Low Temperature, Low Cost Fabrication of Functional and Flexible Materials, Structures and Systems, (3) Cold Sintering and FLASH Sintering of Lead Free Perovskite Oxides and Alumino-silicate Ceramics, (4) Electric Field Driven Assembly Involving Ferroics for Biodevices and Biosensors, (5) Nanoporous and Nanostructured Ferroelectrics, (6) Additive Manufacturing of Ceramics, Polymers, Composite and Conductor Materials. The Vilarinho Research Group is recognized for the contributions to the physico-chemistry of non linear dielectrics and lead free ferroics development and pioneer work on the development of the Seeded Photosensitive Precursor Method (Vilarinho & Calzada) for the low temperature fabrication of ferroelectric oxides on flexible substrates and Electric Field Driven Assembly Platforms Involving Ferroics for Biodevices.
Key words: Electroceramics, dielectrics, non lienar dielectrics, piezoelectrics, ferroelectrics, lead free ferroelectrics, sustainability, FLASH sintering, Cold Sintering, EPD, Additive Manufacturing, Scanning Probe Microscopy, Impedance Spectroscopy.