THEORETICAL MODELING OF PHONON TRANSPORT IN NANOSTRUCTURED SEMICONDUCTORS
In electronics information is transferred with charge carriers, whose motion can be easily controlled with external fields. This is not the case of phononics, where phonons —the basic particles that carry heat— have no mass or charge: this is why we live in a world of electronic devices and heat is normally regarded as a source of loss. The goal of this project is reversing this viewpoint and move to a new paradigm where heat can be actively used to transfer energy, thus information, in a controllable way. This approach allows envisaging a truly zero-power analog of electronics, as in our world heat is indeed ubiquitous and phononics circuits will effectively need no power supply. Additionally, learning how to modulate the heat flow will have also important consequences in conventional electronics —where heat dissipation at the nanoscale is a major issue— or in devising efficient thermoelectric materials. The student will learn how to study heat transport with state-of-the-art computational techniques, including molecular dynamics and density-functional theory.
PLASMONIC NANOSTRUCTURES FOR ENHANCED LIGHT MATTER INTERACTION
Plasmons are the collective oscillations of the conduction band electrons of a metal at the metal-dieletric interface, in response to an external electromagnetic field. These excitations give rise to a variety of nanoscale phenomena widely used in tailoring nanoscale light‐matter interactions to confine light into deep subwavelength volumes. These systems enable unprecedented enhancement of weak optical signal (fluorescence, infrared (IR) absorption, Raman scattering), with important applications in sensing, bioimaging, and photovoltaics. In our group, we have developed a fabrication apprach that enables the scalable fabrication of these nanostructures over large areas. Our target is to use this technique to explore the implementation of these plasmonic structures in real devices to boost their efficiency. Our research is highly interdisctiplinary as it merges physics, optics, materials science, chemistry and device engineering. website : https://projects.icmab.es/enlightment/index.php
LASER FABRICATION OF GRAPHENE-BASED FLEXIBLE ELECTRODES FOR SUPERCAPACITORS
Supercapacitors are energy storage devices for electronic systems that require high pulse power and fast charge / discharge cycles. These devices exhibit long life cycle as well as large specific capacitance, and they are often used as complementary elements for batteries in phones, tablets, watches, sensors, etc. They are also used in high power systems like electric cars, fuel cells and hybrid vehicles. The objective of the proposed project is to fabricate high performance flexible supercapacitor devices based on hybrid nanocarbon-metal oxide electrodes by means of advanced laser processing. Electrodes composed of graphene flakes coated with complex metal oxide nanostructures will be developed. The structural, compositional and functional properties of these systems will be characterized by several techniques (electron microscopies, X-ray and electron diffraction, Raman spectroscopy, electrochemical analyses, etc).
DESIGN AND PHYSICOCHEMICAL CHARACTERIZATION OF ASYMMETRIC-CURCUMINOIDS FOR SENSOR APPLICATIONS
Lineal and conjugated organic molecules are attractive as functional systems that can act as active components in advanced devices. In this sense, symmetric Curcuminoids (CCMoids) are great candidates with a versatile chemistry. In general, CCMoids can be used as molecular platforms capable to (i) attach to electrodes, functioning as nano-wires in nano-transistors, (ii) contact metal centers, for the creation of coordination polymers (CPs) or MOFs, and (iii) emit, depending on the functional groups that form part of the molecule studying the influence of light on their luminescent response. Now, our next purpose is the creation of asymmetric CCMoids toward the creation of molecules that could add extra functions and therefore behave as multifunctional materials in solution, solid state and on surfaces. This project relates to the synthesis and characterization of such types of CCMoids, where the student will learn synthetic procedures as well as plenty of techniques to characterize the systems together with the study of the final properties, which aim is the use of the molecules as sensors and/or switches.
PREPARATION AND IMMOBILIZATION OF RESPONSIVE MATERIALS ON SURFACES
Preparation of supramolecular organic frameworks based on curcumin; Curcumin and its derivatives (curcuminoids) present interesting biological properties. Moreover, there is a huge interest in the developent of new materials using curcuminoids thanks to their versatile properties. The student will study the preparation of supramolecular materials based on the interactions host-guest with curcuminoids to control their properties. Moreover, their immobilitzation on surfaces will be also explored. The student will perform synthesis of the precursors as well as the characterization of the assemblies using different techniques such as ITC, AFM, SEM and TEM.
COMBINATORIAL SCREENING OF HIGH TEMPERATURE SUPERCONDUCTING FILMS BY DROP-ON-DEMAND INKJET PRINTING
High-throughput experimental (HTE) methods are becoming more important in the field of materials science, representing a turning point in the accelerated discovery, development and optimization of materials. The versatility of drop-on-demand inkjet printing allows its implementation with HTE strategies for combinatorial chemistry studies by fabricating complex-shape test pieces with locally-uniform and graded compositions, suitable for parallel characterization of morphological, structural and functional properties. This project will explore such approach together with advanced characterization techniques in order to push forward the optimization in performance of high-temperature REBCO superconducting films, prepared following the recently developed transient-liquid assisted growth chemical solution deposition (TLAG-CSD) route where ultrafast growth rates, up to 100 nm/s, are achieved. Alltogether, the main aim is to promote the use of high temperature superconductors to reduce the negative impact of fossil fuels and enable the full transition to renewable energy alternatives.
GREEN CHEMICAL SOLUTION GROWTH OF FUNCTIONAL OXIDE THIN FILMS FOR SUSTAINABLE DEVELOPMENT
Complex oxides are materials of strong interest because they present a breadth of functional properties with a huge potential range of applications covering from energy harvesting to spintronics. Complex oxide thin films are usually prepared by high vacuum techniques that are complex and expensive, in contrast chemical routes are much more easy, versatile and environmentally friendly. The objective of this project is to prepare complex oxide epitaxial thin films and heterostructures by environmentally benign and energy saving aqueous precursor solutions and to investigate the suitability of these materials for energy harvesting and spintronic applications.
QUANTUM WELLS & NANOPHOTONICS
In our lab, we investigate new materials for electronics and photonics. In particular, we follow two main research lines: 1) TWO-DIMENSIONAL ELECTRONIC SYSTEMS, where electrons are confined in quantum wells. In these materials, we investigate their phototransport properties, with emphasis on the application to neuromorphic devices. We also investigate the electron transport for spintronics applications and we have established collaborations to analyze quantum transport at low temperatures. 2) NANOPHOTONIC METASURFACES, including topological crystals. This project proposes to design photonic crystals, where the propagation of light is protected by special crystal symmetries. The design will be based on active functional materials (e.g., ferroelectrics), which, eventually, could control the flux of light with electric fields. In both projects, the candidate can benefit from our expertise on advanced optical and transport characterization, optical/e-beam lithography and development and characterization of functional optic systems using simulation tools for photonic design.
DESIGN OF AN INNOVATIVE SYSTEM TO PREPARE COATINGS OF MONOATOMIC LAYERS
The possibility to prepare new materials based on monoatomic layers has opened up a novel arena in the fabrication of materials, offering the opportunity to prepare materials that were not possible to fabricate before. The aim of this project is to design and build a new system to prepare materials based on the deposition of monoatomic layers . The student will develop a system with advanced control that will allow the combination of a wide vary of materials with high impact on the semiconducting and photovoltaic industry. The project will be carried out in a multidisicplinary group devoted to prepare materials with novel functionalities.
ADVANCED FUNCTIONAL MATERIALS FOR METAL AIR AND FLOW BATTERIES
Electrochemical energy storage is a strategic support for the implantation of cleaner energy production and use. It can favor grid integration of renewable electricity and its use in emission-free vehicles. The lithium-ion battery is today the most successful technology, but for large scale applications it has clear limitations in cost, energy density and sustainability. Metal-air and flow batteries are chemistries and concepts that can improve these aspects. The student will prepare materials for critical cell components (electrodes, electrolytes or membranes), characterize them by imaging and spectroscopic techniques, and fabricate batteries to test their performance with multiple electrochemical techniques.