While massive photovoltaic (PV) deployment is required, the development of clever technologies that can minimize competition with terrain use (i.e. beyond solar farms) will be necessary (e.g. integrating PV in existing infrastructure and buildings or sharing the land with agriculture). Materials based on earth-abundant elements (oxides and organic semiconductors) will be used and their optical properties will be engineered to tailor the response for selected applications. For instance, the bandgap of these materials can be chemically tuned (for multi-junctions or selective harvesting). Fundamental understanding of aging mechanisms (e.g. evolution of the donor:acceptor microstructure) will be explored using customized XRD Micro Probe System.

New 3D architectures (flexible ultrathin films featuring engineered photonic, magnetic or ferroelectric response) will be developed via scalable nanofabrication techniques to provide novel pathways for light harvesting devices enabling a range of new applications.

Heat is a source of energy coming at very different temperatures and heater shapes, requiring specific point-of-harvest technologies. We will tackle the heat challenge by: i) using thermal anisotropy to improve heat management, investigating quasi-2D systems, such as polymeric thin films, where heat transport can be enhanced by controlling molecular orientation and geometric anisotropy, to dissipate heat from electronic devices more efficiently.

Materials should have high thermal conductivity (at least in certain directions) but not be electrically conductive, as otherwise, they may lead to shortcuts in the circuits. ii) achieve efficient (low temperature) heat to electricity conversion by combining anisotropic thermal properties with advanced doping methods to decouple thermal and electronic transport. Hybridizing thermoelectrics and magnetocaloric systems will also be investigated for wireless charging solutions for powering implantable medical devices. iii) materials capable of heat transport dynamically modified by means of a fast external field (e.g. magnetic, light, etc.) to demonstrate novel phononic device concepts.

EES is key to efficient and large scale deployment of renewable energies, Li-ion batteries leading the way. However, there is strong pressure on raw material cost (e.g. 10-fold increase for LiCO3 for less than 0.2% of electric vehicles today). The ever growing variety of applications (grid, Internet of Things etc.) will worsen the situation. Sustainable and low cost alternatives are urgently needed. Our fundamental understanding of redox and interfacial processes will enable high capacity, sustainable and low cost anodes (Zn, nanostructured, surface engineered Si and new metal alloys), and polyoxometalates as alternatives to vanadium (a critical raw material) in redox flow batteries. Redox mechanisms at atomic level for organic, Prussian blue analogues, MnO2 or blended cathodes will be investigated aiming at enhanced reversibility, hence lower cost per cycle. The use of a large variety of operando techniques (including synchrotron based ones) will be of particular help to such purposes. Our alliance with the ALBA synchrotron is particularly promising for this research, and ensures its viability. Finally, high power supercapacitors based on composites oxide nanoparticles and doped nanocarbon produced at competitive costs by advanced laser processing will also be investigated.

Green fuel production, particularly hydrogen, is an important part of the new RePowerEU plan aiming at replacing almost 10% of Russian gas consumption with hydrogen power. However, achieving cost effective green fuel production remains a challenge and effort within Matrans42 will be dedicated towards the development of novel low cost, highly stable and efficient (photo)catalysts for alcohol reforming, water electrolysis and splitting using sun light. In particular, thin films or nanostructured composites based on aerogel/lyogels, graphene based materials, metal-organic-frameworks (MOFs) and non-noble-metal glasses or oxides nanoparticles (such as Ce-Al-based and Ti-based metal glasses, TiO2, ZnO, graphitic C3N4, etc.) will be explored. New synthetic methods such as high-power laser-induced crystallization in liquid media and supercritical CO2 will be used targeting low moderate production costs and optimum catalyst stability. Finally, multi-functionalized 3D graphene oxide aerogels will also be used as a catalyst for hydrodeoxygenation (HDO) reaction of CO2 or bio-oil (derived from biomass) to produce valuable fuels. Enhanced process sustainability will be achieved by adding functionalized MOFs capable of in-situ production of H2 (necessary for the HDO).

High-temperature superconductivity (HTS) will provide zero emission targets by enabling fusion power, expanding renewable energy and facilitating zero emission transport. To deploy these technologies, we need R&D in HTS, from materials fabrication to their customization for integration into devices. The challenges we foresee are i) Generate fundamental knowledge of the transient liquid assisted growth non-equilibrium ultrafast growth process (made in ICMAB), as a game-changer for high-throughput HTS nanostructured materials, with ALBA synchrotron's newly developed in situ synchrotron platform and machine learning optimisation approaches, with the idea of transferring this technology to industry; ii) Investigate the physics of vortices under extreme conditions (magnetic field, frequency) and their impact on mechanical-electrical-thermal properties (simulations and tests) to fill the knowledge gap and enable HTS materials for large-scale energy-efficient applications in fusion, power transmission and high energy physics, fostering existing collaboration with key research infrastructures (CERN) and industries.