Li-ion battery is ubiquitous and has emerged as the major contender to power electric vehicles, yet Li-ion is slowly but surely reaching its limits and controversial debates on lithium supply cannot be ignored. New sustainable battery chemistries must be developed and the most appealing alternatives are to use Ca or Mg metal anodes which would bring a breakthrough in terms of energy density (specific capacity of Mg and Ca, respectively, 2200 and 1340 mAh/g, as compared to 372 mAh/g for graphite in Li-ion) relying on much more abundant elements (Ca and Mg being the 5^th and 8^th most abundant elements on the Earth’s crust, respectively, whereas Li is the 25^th). Currently, the main bottleneck for the development of Ca or Mg based technologies is the lack of electrolyte allowing for reversible Ca or Mg electrodeposition and having a large electrochemical stability window enabling the use of high voltage cathode.

The overall objective of the work is to assemble safe Ca and Mg metal anode based batteries with optimum power performances and high energy density. This will imply the assembly and balancing of full cells at the laboratory scale (Swagelok and coin cells) but also larger pouch cells in collaboration with CIDETEC (Basque country, Spain) with whom nail penetration tests will be performed. Post mortem analyses (SEM-EDX, FTIR, XPS …) will also be undertake in order to clarify the fading mechanism of the first generation cells. The PhD student will investigate the plating/stripping and the insertion/deinsertion mechanisms, respectively, on the anode and the cathode sides by means of several electrochemical methods (Electrochemical quartz crystal microbalance, rotating disk electrode and electrochemical impedance spectroscopy). In situ X-ray diffraction (XRD) and infrared spectroscopy (FTIR) will also be implemented and proposals will be prepared to access synchrotron facilities. The influence of the electrolyte formulation (developed by other team members) on these mechanisms will also be studied.

The project will mainly consist in the design and synthesis of novel organic stable radicals for their implementation as active components in molecular electronic devices. Organic radicals have awakened much interest for its wide applicability such as magnetic materials, imaging agents, catalyst, electrochemical active materials, among others. For this, the aim of the project is to develop novel redox and magnetically-active materials based on organic radicals to be applied in the field of electrochemical energy storage, sensors and/or organic memories. Different approaches, such as the blending of the organic radical with carbon-based materials, will be explored. The candidate will be involved in the synthesis, material processing and characterization. The department is actively involved in implementing nanotechnology and sustainable and economically efficient technologies for preparing advanced functional molecular materials. The candidate will join a group that is actively focused on the development of novel Molecular Electronic Materials and Devices. Particularly, our areas of interest include synthesis of novel functional molecules, surface self-assembly, molecular switches, organic field-effect transistors, charge and spin transport and organic-based (bio)-sensors among others. The group counts with all the required equipment and installations for a successful project development.  

The candidate will be able to join a pioneer, dynamic and active group from the Department of Nanoscience and Organic Materials (NANOMOL) from the Institute of Materials Science of Barcelona (ICMAB-CSIC). The candidate will perform the PhD in a very interdisciplinary environment and will be part of a research group composed of chemists, physicists and engineers. For this, the candidate should have the ability to work in a team formed by researchers with different backgrounds and from different nationalities. In addition, the successful candidate might travel to other European countries to develop the project in the framework of established scientific collaborations or to present the results of his/her research in conferences and schools.

In the last decades there has been a great effort on the fabrication of solid-state molecular electronic devices. Inexpensive, functional and atomically precise molecules could be the basis of future electronic devices, but integrating them into real devices will require the development of new ways to characterize them and to control the interface between molecules and electrodes. The goal of the project is the design and preparation of molecular memory elements based on hybrid materials formed by molecular switches, redox-active and/or photochromic, adsorbed onto conductive substrates. The preparation of self-assembled monolayers (SAMs) or thin films will be a key step of the fabrication. The charge transport measurements across the layers will be performed to investigate the conduction mechanism as well as using the electrical response as the output of the switch upon external modulation of the film. For the electrical characterization of these molecular junctions we will work with a novel technique that basically consists in using a liquid metal as the gallium indium euthectic (EGaIn) to top contacting the molecular active layer. This technique is easy and very versatile and allows forming a soft contact with the layer which is highly desired to avoid molecular damaging or short circuit by the penetration of metal atoms.

On-surface synthesis has provided an unprecedented route toward the formation of atomically precise surface nanostructures and  functional architectures with highly chemical stability and novel physical properties. As a versatile bottom-up strategy for the construction of covalent bonds between molecular building blocks, on-surface synthesis has gained strongly increasing research attention during the past years [1]. This project aims at the bottom-up synthesis and investigation of novel one- and two-dimensional (1d, 2D) carbon-based networks on surfaces that could not be synthesized in solutions, by exploitation of the surface reactivity and the intermolecular interaction of organic molecules.  The organic molecules used as molecular building blocks and precursors will be deposited on the surface in ultra-high vacuum (UHV) by an innovative method consisting of a novel atomic layer injection system, allowing us to select new organic molecules which cannot be sublimated. One of the major challenges consists in the selection of the appropriate solvent and conditions which permits the production of micro-drops of the molecular solution and is evaporated during the travel through vacuum to the surface so that a pure molecular layer can be formed. The influence of the underlying surface to the on-surface reactions will be exploited. One important part of this project is the in situ characterization of the layer in UHV by surface sensitive techniques, e.g., scanning tunneling microscopy (STM), noncontact atomic force microscopy (nc-AFM), and X-ray photoelectron spectroscopy (XPS), which allows us to get both the structural and chemical information with high resolution. The project will use novel organic molecules synthetized in the group of Prof. Nuria Aliga susceptible of being use as responsive materials. 

The ESR will be trained in standard surface sensitive techniques, advanced scanning probe microscopy methods (STM, nc-AFM) in UHV and photoelectron spectroscopy and will work in a collaborative project of physicists and chemists.

Electronic devices based on digital processing have completely changed our lives. We have witnessed miniaturization and improving performances since the invention of the electronic transistor in the mid past century. However, this wonderful progress has physical restrictions in energy dissipation and emerging quantum phenomena. A suggestion for a paradigm change is the use of spintronics—that considers the intrinsic spin of electrons and the corresponding magnetic moment—as an alternative to conventional electronics. Recent developments in spintronics have shown that spin excitations (spin waves) such as skyrmions or vortices have topological properties that might lead to new applications.Digital systems simplify the complexity of physical quantities in discrete levels and thus avoid unwanted changes caused by noise or fabrication defects. On the other hand, nature taught us that powerful machines that embrace complexity are possible: the brain. Biology has inspired many researchers to study new post-digital systems based on neural networks and proposed functionalities for devices.

This thesis project proposes to study spin excitations in materials and the implementation of computing strategies using nanostructures and metamaterials (materials that have been structures artificially). The aim is to develop functional magnetic nanodevices that work at low power by using electric fields (or strain) and light instead of currents and magnetic fields. Examples of the proposed functionalities include computing with waves and delays, pattern recognition based on synchronization, or memories based on phase differences among oscillators (phase coding). The project has an important part that relies on device nanofabrication and thus the candidate will take part in the design and fabrication of nanodevices using state-of-the art techniques for lithography and materials’ growth; the candidate will have access to the clean room facilities and also to the advance materials’ characterization setups available in our institute (ICMAB).

Nanoscale heat transport has emerged in the last 10 years as a field of increasing interest towards efficient energy regeneration.  Thermoelectricity is possibly one of the fields that has captured largest attention from the science and technology perspectives due to its possible applications to waste heat recovery and improvement in renewable energy generation. Clearly, any breakthrough will come from the use of nanostructured materials.  However, our understanding of heat transport at the nanoscale is still in development, e.g., few is known on the wave nature of heat. The specific tasks to be conducted within this project are:

• Development of a pump and probe imaging technique in the time- and frequency-domains simultaneously. Development of the measurement and analysis numerical tools.
• Fabrication of the samples through molecular beam epitaxy, spin casting, and blade coating. General structural and chemical characterization of the samples (SEM, Raman, Optical spectroscopy, etc)
• Measuring the fabricated samples 

We aim to pave the way towards efficient heat manipulation. We will study heat propagation in ultraslow motion in quasi 2-dimensional (2D) hybrid systems based on suspended silicon nanomembranes and polymer thin films. We aim to investigate the development of heat waves (second sound) as well as the influence of inorganic/organic thermal boundary resistance in the resulting thermal distribution. For this purpose we will develop a full novel approach based on optical interferometry and frequency- and time-domain thermoreflectance. The samples will be imaged through this technique with high spatial resolution (about 200 nm), high temporal resolution (about 30 ps), and high temperature resolution (about 100 μK), and through reconstruction of the data we will produce a live video of the evolution of a single heat pulse. All experiments will be carried out in a pump-and-probe configuration and as a function of temperature between 5K and 600 K. The obtained thermal videos will not only be a fully new experimental development, but will be the key to understand heat propagation in these quasi 2D systems. The samples will be fabricated by combining molecular beam epitaxy for the inorganic material component, and combined with blade and spin coating to deposit diverse polymers. We expect that the successful output of this project will have impact on establishing the wave-like thermal propagation regime, as well as establishing a new optical technique to study nanoscale heat transport.

Solar photovoltaics (PV) is a key technology for the global energy transition; solar power could provide 15% of Europe’s electricity by 2030. Despite commercial Silicon PV modules have been remarkably successful they present some concerns to meet the energy demands: efficiency, life and performance with time. An all-oxide PV approach is very attractive due to the chemical, mechanical and thermal stability, nontoxicity and abundance of many metal oxides that allow preparation by cost-effective and scalable techniques. The use of ferroelectric perovskite oxides (FEPO) as a stable photoactive layer has opened up a ground-breaking new arena of research. They present an alternative mechanism for solar energy conversion that could surpass the fundamental efficiency limits of conventional semiconductors. Unfortunately, most FEPO are wide-band gap materials (use only 8-20% of the solar spectrum) and  present poor charge transport properties.

The main goal of this project is to develop an all-oxide device based on FEPO with improved light absorption and carrier extraction using abundant and lead-free materials by low cost and scalable chemical methodologies. This project will build on recent results where it has been observed that cobalt substitution in ferroelectric BiFeO₃ allows band gap tunability and remarkable improvement in photocurrent. In order to unlock the full potential of the BiFe_1-xCo_xO₃ (BFCO) system and gain new insight on its PV mechanism, improved and simplified innovative architectures based on compositional tuning of BFCO and interface engineering will be developed. 

The student will be trained on cost-effective chemical deposition techniques (combining solution processing and atomic layer deposition) to prepare complex oxide thin films with atomic control. The student will also be trained on characterizing the structure, morphology and chemical composition of the developed films by means of x-ray diffraction, scanning electron microscopy, atomic force microscopy and x-ray photoelectron spectroscopy, respectively. Optical characterization and PV evaluation will also be carried out in optimized films.

Metal/air batteries are among the most promising novel battery chemistries. They could allow up to 3-5 times the specific energy of current Li-ion batteries while significantly lowering their cost. In spite of intense investigation efforts in the past few years still their performance and durability are not satisfactory to establish as a technology. This is mostly attributed to the lack of an optimal control of the complex reduction processes of oxygen that need to take place quickly and reversibly. Remarkable improvements can be achieved by alternative paths involving soluble catalysts (redox mediators, RM) in the electrolytes. The use of RM also facilitates operation in flow cell architecture, by which also higher power can be achieved.

This work aims to the development of efficient and stable RM for metal/air flow batteries. We have recently shown that multiredox nanosized oxides, such as polyoxometalate clusters are promising RM [1]. In particular their stability seems superior to that of more common organic molecules. We propose to extend the study to other oxide nanoparticles and to elucidate in more detail electrode and interparticle charge transfer mechanisms, and strategies for improving kinetics and stability. Many oxides are already known by their reversible redox activity in oxidation and reduction processes and in many cases by their catalytic activity, which would add a second advantage in O₂ redox process.

The ESR will participate to the development of more efficient, price effective metal/air batteries in the group. In particular he/she will:

• Develop oxide clusters and hybrids by wet chemistry.
• Investigate these materials and their behavior in the electrochemical systems using microscopic, spectroscopic and electrochemical techniques.
• Develop, model and test flow cells based on the electrochemistry of these materials.

The candidate will work in a rich and multidisciplinary environment at the “Advanced Characterization and Nanostructured Materials” (ACNM) group at the Materials Science Institute of Barcelona (ICMAB). The group has a long-standing record of high quality publications in the field of functional oxide materials for novel technologies. Our research is both of basic and applied character since it is aimed not only to investigate the relation between the microstructure and properties but also its potential application for the design and fabrication of novel magnetoelectronic devices. The student will be responsible for the preparation of thin films and heterostructures, their structural characterization and to perform and analyze their spin transport properties.

About two thirds of the energy generated is lost in the form of heat. Low quality, distributed sources of heat are ubiquitous, yet go unused because they are unsuited for conventional heat engines. Solid state thermoelectric devices, able to convert heat gradients in electrical current, do not depend on any moving parts and can be scaled nearly arbitrarily, both for heat micro-generation as well as to the large scale. However, the main reason that thermoelectric generators have not seen general adoption is because they are so far based on inorganic materials. This makes them prohibitively expensive for large surface applications.  Low cost, flexible and non-toxic sustainable materials on the other hand could make thermoelectricity widespread, if their efficiency is sufficiently raised.Cellulose constitutes an almost inexhaustible biopolymer, being the most abundant renewable polysaccharide produced in the biosphere. Cellulose can also be synthesized by bacteria, produced by microbial fermentation. Bacterial nanocellulose (BC) has the same molecular formula as plant-derived cellulose but it also permits the  possibility to interfere on its micro(nano) structuration and composition both during and after the bacterial biosynthesis.  This offers to  materials scientists a model biopolymer to fabricate electrically conductive and thermally insulating composites with tuned characteristics in terms of large surface, thickness, porosity, (p and n) doping or biodegradation.

The main objective of this PhD project is to develop efficient, thermally stable, flexible and biodegradable thermoelectric devices. For that, we propose the growth of bacterial nanocellulose as sustainable biopolymer matrix in combination with semiconducting CNTs and other conductive phases. By using judiciously optimized electronic doping and porosity, we expect to obtain thermally stable thermoelectric paper that can be easily integrate in devices. The interdisciplinary nature of the current project, bridge expertise in device physics, materials preparation, and bacterial cellulose growth.

Over the recent years, we have investigated the properties of quantum wells (QWs) at the LaAlO₃/SrTiO₃ interface, including 2D superconductivity, Rashba spin-orbit fields and lattice vibrational modes [1-3]. More recently we uncovered persistent photoconductance (PPC), whereby the system changes its conductance in a plastic way, retaining memory from its past history, as in the case of memristors, but using light instead of electric pulses. Our most astounding discovery (yet unpublished [4]) is that light pulses can be used to replicate spike timing-dependent plasticity (STDP). STDP was proposed to emulate time causality of electro-chemical signals in biological neurons: pre-synaptic neurons spiking after post-synaptic neurons are “anti-causal” and learning is weakened; pre-synaptic neurons spiking before post-synaptic neurons are causal, reinforcing learning. STDP enables unsupervised learning, without need of labelling training data. Our discovery is particularly relevant, as it extends the STDP concept beyond electrical stimuli to the realm optical stimuli, opening up whole new perspectives on neuromorphic engineering and in artificial vision. More specifically, our project aims at generating neuronal spikes in our physical system –e.g., using, among other approaches, RC differentiators, where R and C are defined in the QWs–. The candidate will be trained in Python-based algorithms that will help to understand how artificial networks can be designed to learn from visual inputs, with the ultimate objective of building a first design that may learn from simple visual patterns.

The student will be acquainted with state-of-the art techniques that allow real-space imaging with diffraction limitation [see our References below]. This is relevant for the full characterization of synaptic-like devices excited by short optical stimuli. Artificial neuron networks will be defined so that electric transport can be done with in-situ excitation of the small synapses by optical stimuli controlled to timescales down the microsecond. The candidate will be responsible with defining the required devices in the clean room facilities using optical and electron-beam lithography to define small optical devices with length scales from around 100 nm up to around 100 microns.

Over the last years our investigation on photonic and plasmonic crystals has revealed photonic / plasmon effects that increase the magneto-optic response [1-4]. Additionally, we have demonstrated the nonreciprocal propagation of plasmons in the presence of magnetic fields [4]. All this research is relevant to achieving unidirectional propagation of spatially confined electromagnetic waves, indispensable for the development of on-chip optical communications in photonic circuitry. To further push the boundaries of the field of nanophotonics, we will pursue two distinct approaches that aim towards creating actively controllable nanophotonic devices: (i) integration of electro- and magneto-optic materials into nanophotonic metasurfaces to enable using electric (magnetic) fields to control confined electromagnetic waves; (ii) special topologies designed in the wavevector space that enable helical edge propagation of modes that flow unimpeded by imperfections or back-reflections. The latter are akin to quantum spin Hall in fermionic systems, which have been demonstrated in honeycomb photonic dielectric lattices. The candidate will use primarily these tools: (i) Finite-difference time-domain simulations to design metasurfaces and topological photonic crystals; (ii) Angle-resolved reflectance/transmission spectroscopy, which can resolve reciprocal space maps from near-IR to violet, with scanning beam sizes down to few microns. Particularly, beyond the more common real space imaging, this methodology will enable the direct visualization of helical edge states and Dirac cones in the photonic crystal band structure. 

Diffraction techniques have had a crucial role in the study of the structure of new materials as they have allowed understanding the key relation between structure and properties, especially in transition metal oxides. In epitaxial thin films (~10-100 nm in thickness), exploiting the overall information that X-ray diffraction can offer has been elusive due to the small amount of sample they contain. The research project proposed here consists in developing two different methods to push forward present capabilities in this field.

-The first consists on obtaining information on the field of deformations inside the film (strain). This strain field makes diffraction peaks to deform in a way that contains information about the deformation field. Recovering this information is a difficult task as it requires iterative approaches involving complex calculations. Our objective is to adapt different algorithms already develop for similar problems, developing specific computer software able to make these calculations in a reasonable amount of time. As a second step, the objective will be to interpret the obtained results in terms of a strain field. This objective will require the use of data collected at synchrotron sources.

Due to technological limitations associated with the use of silicon, substantial efforts are currently devoted to developing organic electronics and, in particular, organic field-effect transistors (OFETs). Indeed, the processing characteristics of organic semiconductors make them potentially useful for electronic applications where low-cost, large area coverage and structural flexibility are required. However, in order to move towards applications, there are some fundamental aspects that need to be further understood to be able to achieve high performing devices with high reproducibility. One important and attractive niche of applications of OFETs is the development of novel low-cost sensing platforms. OFETs can be applied to transmit information about our environment, such as light/radiation sensors, pressure or deformation sensors or for the development of (bio)sensors.

In this project, we will optimize the device performance by controlling the organic semiconductor properties such as the molecular design, formulation and crystallization of the material, among others. Further, the electrical response of the devices when they are exposed to different external stimuli will be explored in order to develop novel promising sensors.

This project is part of the ERC Advanced Grant ULTRASUPERTAPE which aims to demonstrate an unprecedented approach for fabrication of low cost / high throughput / high performance High Temperature Superconducting (HTS) tapes, or Coated Conductors, to push the emerging HTS industry to market. The breakthrough idea is the use of Transient Liquid Assisted Growth (TLAG) from low cost Chemical Solution Deposition of Y, Ba, Cu metalorganic precursors by ink jet printing to reach ultrafast growth rates. We have just demonstrated growth velocities of 100 nm/s which are 100 times larger than standard film growth methods. ULTRASUPERTAPE aims to boost Coated Conductor performances up to outstanding limits at high and ultrahigh fields, by smartly designing and engineering the local strain and electronic state properties of nanocomposite superconducting films prepared from nanoparticle colloids. This PhD grant will contribute to the project with the study of the superconducting properties to find the optimal growth conditions and optimal compositions for increased performances by analysing samples produced by ink jet printing combinatorial chemistry apaches. Special attention will be devoted to study the vortex pinning mechanism and correlation with the microstructure of superconducting nanocomposites films and tapes to achieve exceptional performances.

The fellow will study the physical properties of high temperature superconducting films and tapes prepared by chemical solution deposition and ink jet printing combinatorial chemistry approaches, with the following focus directions:

• Study of basic superconducting properties of films prepared by ink jet combinatorial chemistry approaches using adequate techniques.
• Correlate the physical properties with deposition and growth parameters
• Study the vortex pinning mechanisms of the superconducting films and tape and correlate them to the nano-microsturcture defect landscape of the films.
• Investigate the doping effect in the superconducting nanocomposites films to boost superconducting performances at ultrahigh magnetic fields

The research aims at producing magnetic nanoparticles coated either with SiO₂ or with a thin layer of gold and, additionally, gold and CdSe nanoparticles. The coating layers are chosen as to link on them hollow spheres so as to produce tetragonal or hexagonal arrangements. These, by their disposition, will produce holes through which ions can penetrate that can reside in the voids between the surface of the bulk material and the spheres.  These ions can be of different nature and their charge can be totally or partly compensated by the charge of the core, e.g. the gold nanoparticle can be negative and this charge is compensated by a layer of ions. This leads to a charge separation in a inspiring way as what happens in a cell or in a capacitor. The nature of the hollow spheres can be distinct, e.g. a photoredox catalyst will be added as a hollow sphere. In these cases light harvesting catalysts will be produced. These materials are produced for a purpose, either as a drug delivery agent, molecular electronics, photoredox catalysis, or electrical energy storage. 

The continuous increase in computational power has fueled the development of methodologies that allow the simulation of materials with atomistic resolution from fundamental physics and chemistry. We use them at ICMAB as a kind of “theoretical microscope” to understand all sorts of properties of organic and inorganic systems from an atomistic perspective, looking at the organization and motion of atoms and molecules. Using advanced methodologies such as ab initio molecular dynamics or reactive force fields molecular dynamics we can now even follow chemical reactions taking place over specific substrates.

We propose to employ these cutting-edge simulation methodologies in a combined theoretical-experimental work to design new low-dimensional molecular architectures by polymerization over inorganic substrates. The well-defined bottom-up creation of such polymeric systems out of small individual units (oligomers) has attracted enormous interest in multidisciplinary fields such as sensing and molecular electronics.

The motivation for the project is the current difficulties in preparing the desired tailored hierarchical structures in solution and the fact that many relevant oligomers cannot be sublimated. To overcome these difficulties, we propose to follow a novel approach in which selected inorganic surfaces are employed for confining polymerization, exploiting surface reactivity and intermolecular interactions. The use of computational methods, combined with experimental scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS) data, providing the structural and chemical information at submolecular level, will be employed for rationally designing and preparing the appropriate hierarchical growth of the desired molecular structures.

This PhD project is focused on the fabrication and advanced characterization of novel multiferroic frustrated oxides with strong magnetoelectric coupling. Frustration, or the inability to satisfy all interactions, leads to new fascinating phenomena and properties (quantum magnets, spin liquids, chiral spin orders, magnetoresistance, etc.). The discovery of new classes of frustrated materials in which the charge, orbital, magnetic or elastic orders and the (ferro-)electric properties are strongly coupled (improper multiferroics) is generating a flurry of activity in the fundamental and applied field. The list of potential applications is still incomplete: spintronic devices, multi-state memory units with reduced energy consumption, smart sensors, switches, etc. New physical mechanisms generating coupling between coexisting internal orders will be explored and investigated in materials in different forms (from polycrystal to single crystal and thin film). Their understanding will help to foster them in order to obtain coupled improper multiferroics for room temperature operation.   

The activities of the CMEOS group at the ICMAB center on strongly correlated materials of interest in Condensed Matter research and for Information Technologies. Our group has long-standing expertise and international recognition on advanced structural, magnetic and electronic characterization using neutron and synchrotron techniques. We combine experimental and theoretical crystallographic approaches to tackle the structure-properties relationships. The research will involve material fabrication and advanced characterization using state-of-the-art techniques. Selected 3d and 4d magnetic oxides with topological, magnetic or electronic frustration and spin-orbit coupling will be investigated as the richness of possible magnetoelectric mechanisms greatly exceeds our expectations. A key component of the project will be neutron and X-ray scattering experiments at international facilities to uncover magnetic, charge and structural correlations and confront theory.

The science behind Photovoltaics (PV) in semiconductors has been understood for decades. In the present project it is proposed to overcome the PV efficiency limits present in PV technology based on semiconductor materials exploring a peculiar kind of materials, called ferroelectric materials, that may offer a powerful new mechanism for converting light into electricity.

Ferroelectric materials are those materials that demonstrate switchable spontaneous surface charge upon application of electric field. If surface charge is not properly screened ferroelectric materials can hold a giant electric field (overpassing those appearing in semiconductor), which can potentially lead to large efficiencies, in principle forbidden for semiconductors technology. The drawback of ferroelectric materials is their large bandgap and low carrier mobility. The most commonly followed strategy by the scientific community to overcome these issues is to investigate on new materials that can show larger absorption and larger carrier mobilities, usually at expenses of good ferroelectric properties. Another possible route is the combination of ferroelectric materials with other materials showing larger absorption. This route presents the main disadvantage of that the place where the photocarrier is generated is not the same where the electric field generated by the ferroelectric material is present. Recent theoretical works have shown that appropriate combination of some unit cells thick layers of appropriate materials; can combine good ferroelectric properties with high absorption. These properties would be present all across the material resulting in a new uniform band diagram, meaning a new material.

Pulsed laser deposition (PLD) will be used to growth the proposed materials. The selected material constituents will be based on BaTiO3 which is a ferroelectric material with large polarization at room temperature and free of any toxic element that can hinder applications.

Electrokinetics and catalysis play a determinant role on the energy efficiency of electrochemical devices for CO₂ capture and reduction. The PhD candidate will work on the following objectives: (1) development of electrolyte formulation (2) synthesis and characterization of electrocatalysts (3) evaluation of the reversibility of the electrodes towards the nucleophilic attack (4) proof-of-concept of a full cell prototype to produce concentrated CO₂ stream (5) coupling to CO₂ electroreduction device to demonstrate the feasibility of a CCU concept.

CO₂ capture from industrial emissions or air and its subsequent conversion into useful products (CCU, carbon capture and utilization) is one of the current challenges in chemistry to achieve negative emissions. Most CO₂ capture methods are energy intensive, involving thermal cycles or differential pressure. The project will deal with the use of electrochemical cycles to capture CO₂ and release it in pure form. These cycles typically rely on electrochemical generation of nucleophiles that attack CO₂ at the electrophilic carbon atom, forming a CO₂ adduct. Then, CO₂ is released in pure form via a subsequent electrochemical step. Once purified, CO₂ will be reduced to useful C₂ products such as ethanol or ethylene. The fellow will develop novel electrocatalysts to avoid the use of platinum group materials. Simulation tools will be employed to optimize the electrochemical cell configuration, and several prototypes will be fabricated by 3D printing for its validation.

The candidate will gain fundamental knowledge on CO₂ reduction processes and mechanisms. The candidate will also acquire experience on the design and development of new functional nanostructured materials and on the use of advanced structural, chemical and electronic characterization techniques as well as system development.

The circular economy of CO2 is nowadays a hot issue for our society. Nevertheless its successful implementation still requires a lot of new knowledge and its implementation in reliable systems. Therefore, the suitability of nano catalyst that enhance the reduction process of CO2 toward wanted subproducts as well as the complementary oxidation reaction taking place in the anode constitute basic key points. The combination of 3D nano skeleton with advanced design of nanocatalyst particles become one of the challenges for implementing high efficiency systems. The control of the charge transfer mechanisms at the nano scale level is required to develop advanced cathode and anodes increasing the appropriate electrochemical activity, reducing overpotentials and increasing the current density in order to have feasible energy balance with a high productivity. Different nanoparticles compositions with the presence of different additives will be explored in order to estimulate the charge transition processes for contributing to descrease the required overpotential as well as the increase of the active sites. Compositional, morphological and structural features will be explored.

Nano catalyst materials play a determinant role in the electroreduction of CO2. In this field, the PhD candidate will work on five main directions: i) development of catalyst materials for reduction of CO2; ii) development of catalyst materials for the complementary anodes; iii) characterize the nano catalyst functional properties, iv) development of a prototype system improving also electrolytes and membrane. v) scale up of the system to validate feasible industrial application of the developed electroconversion system. Aside of the standard CO2 subproducts, special attention will be paid in the production of carbon double bonds.

The candidate will gain fundamental knowledge on CO2 reduction processes and mechanisms. The candidate will also acquire experience on the design and development of new functional nanostructured materials and on the use of advanced structural, chemical and electronic characterization techniques as well as system development.

Metal air batteries constitute a challenge issue for achieving a high capabilitiy of electrical energy storage. It defines a clear alternative to Li-ion based batteries offering high energy density and avoiding the mandatory electrical recharge as metal air allows also mechanical research replacing exhaust electrolyte for a fresh one. Likewise, it gives rise to the posterior treatment of exhaust electrolytes to recovery materials and, thus, closing a loop for the circular economy of the battery function. Therefore, attention will be also devoted to the battery performance specially considering the scale up of the system for achieving high efficiencies.

Nano catalyst materials play a determinant role in the anode functionality of metal air batteries. In this field, the PhD candidate will work on the following main directions: i) development of catalyst materials for improved anodes; ii) characterize the nano catalyst functional properties, iii) development of battery prototypes iv) scale up of the system to validate feasible commercial applications v) recycle the exhaust electrolyte..

The candidate will gain fundamental knowledge on oxidation processes and mechanisms as well as the conception design and implementation of metal air batteries. The candidate will also acquire experience on the design and development of new functional nanostructured materials and on the use of advanced structural, chemical and electronic characterization techniques as well as system development.

Within this project, the PhD candidate will develop macroscopic triboelectric generators based on nanowires. Triboelectric generators take advantage of the electrostatic charges created on the surface of two dissimilar materials when they are brought into physical contact. In particular, the candidate will develop generators able to convert mechanical work in the form of a lateral displacement to develop the generators that will include arrays of nanowires.

The investigation of nanomagnetism on a fast time scale is crucial for the development of novel, improved devices like sensors and memory, logic or neuromorphic elements for advanced information technology. 

The PhD projects comprises the development, commissioning and use of new instrumental equipment which will increase the bandwidth of electrical signals that can be applied to samples in the X-ray Photoemission Electon microscope (XPEEM). This new capability will be exploited to perform experiments on magnetization dynamics inaccessible with current techniques, making use of the high spatial resolution of the XPEEM (down to 20 nm lateral resolution). To this end, the candidate will be involved in sample preparation by lithographical methods, basic sample characterization by laboratory techniques and will plan and perform measurements during beamtimes at the PEEM using X-ray magnetic circular and linear dichroism (XMCD/XMLD) contrast, and data analysis. She/he is expected to obtain measurement beamtime in regular competitive calls for proposals (with the help of the advisors).

The candidate will join a running research project on nanoscale magnetization dynamics driven by surface acoustic waves (SAW) [1], a collaboration between the ALBA PEEM group and Dr. Ferran Macia with coworkers. New experiments enabled by the expected higher (low GHz) bandwidth will target the interaction of SAW with spin waves (magnons) and the investigation of spin waves excited by a more conventional induction method, but in epitaxial materials which are not compatible with measurements in transmission. Additionally, the established SAW excitation technique (in the 100s of MHz range) will be applied to selected new magnetic systems of interest.

This project aims to develop a technique to measure the transverse beam size of a particle beam in a circular accelerator. Circular accelerators produce Synchrotron Radiation (SR) when the particle beam is bended at magnetic structures. The technique will consist on using the x-ray part of the synchrotron radiation to illuminate a material based on a suspension of Brownian nanoparticles and studying their interference pattern. The transverse coherence of the source and therefore, under the conditions of validity of the Van Cittert-Zernike theorem, the transverse electron beam size are retrieved from the pattern between the synchrotron radiation and the spherical waves scattered by the material. In classical optics, this kind of interference pattern is known as Heterodyne Near Field Speckles (HNFS) pattern.  

 While HNFS is a well-known particle sizing technique in optics, it has never been used for beam size monitoring in particle accelerators. One of the main fields of research involved in this project involves the required characteristics of the Brownian suspension of nanoparticles: diameter of nanoparticles, material, concentration, etc.  These characteristics need to maximize the contrast of the speckles produced by the interference pattern, which are captured using scintillator screens and imaging system downstream the Brownian suspension.

 First tests have been carried out in a beamline at ALBA using Silica colloids and using the synchrotron radiation produced by an undulator, so that monochromatic x-rays of 10 keV can be easily produced. Nevertheless, the project includes the possibility to perform such experiments using bending dipoles and wideband monochromators, so that this technique can be easily applied to other synchrotrons (like the Future Circular Collider at CERN).