One-day monographic course.
23th September, 2025.
Director: J. A. Alonso
Program:
1- J. E. Rodrigues (ESRF, Grenoble): General aspects of Raman spectroscopy
2- M. A. Bañares (ICP-CSIC): In situ studies of materials for catalysis
3- F. Agulló-Rueda (ICMM-CSIC): Raman microscopy
4- O. Frank (JH-Inst, Prague). Localized Raman micro-droplet in-situ spectroelectro-chemistry of 2D materials
Severo Ochoa Centers of Excellence program, Grant CEX2024-001445-S
P. Camarero, E. Rincón, P. Haro-González, F. Agulló-Rueda, A. García-Cabañes, M. Carrascosa, «Light-induced Accumulation of Micro- and Nano-Plastics from Water Dispersion by Optoelectronic Lithium Niobate Platforms,» Adv. Mater. Interfaces XX, e00462 (2025).
Plastic contamination in marine and drinking water is a major concern in environmental research. Particularly, detection and identification of micro and nanometric particles remain as important challenges, and so, several emergent methods are currently being investigated. Here, an optoelectronic platform is presented for trapping and accumulating micro/nano-plastics dispersed in water. The system exploits the photo-induced electric fields generated by visible light in LiNbO3:Fe crystals. When light is focused on the crystal, the photogenerated electric field triggers successive ejection of tiny droplets from the aqueous sample. These droplets reach the illuminated surface and evaporate leaving behind accumulated particles. Efficient accumulation of polystyrene microparticles is achieved down to 1 µg L−1. The influence of plastic concentration and illumination time are characterized. Moreover, the method is further validated at the nanoscale using 140 nm diameter polystyrene (PS) nanoparticles. Its functionality in saline water dispersions is also confirmed although exhibiting a lower efficiency. Finally, the platform´s versatility is demonstrated by accumulating other plastic contaminants such as polyethylene (PE) and polymethyl-methacrylate (PMMA), and a mix of PE and PS. The resulting accumulation spots serve as suitable samples for plastic identification by Raman spectroscopy. Overall, these results highlight the potential of optoelectronic lithium niobate platforms for micro/nano-plastics capture, accumulation and Raman identification.
Jorge Hernández Velasco asistió al acto de celebración del 25 aniversario del Programa Ramón y Cajal para financiar contratos de investigación posdoctoral de excelencia. El evento, presidido por la ministra de Ciencia, Innovación y Universidades, Diana Morant, se celebró en el Gran Anfiteatro del Ilustre Colegio Oficial de Médicos de Madrid y contó con la presencia, entre otras autoridades, de la presidenta del CSIC, Eloísa del Pino Matute, y de José Manuel Fernández de Labastida, director de la AEI. En el grupo Nanocarma disfrutaron de un contrato Ramón y Cajal Ángel Landa Cánovas y Jorge Hernández Velasco.
Vídeo resumen del acto de los 25 años del programa Ramón y Cajal
Y. Mendez-González, J.D.S. Guerra, F. Agulló-Rueda, O. Peña‐Rodríguez, A. Fernández García, M. Manso Silvan, «Evolution of the structural and optical properties of La doped silver niobate-based thin films,» Mater. Sci. Eng. B 323A, 118667 (2025).
A detailed investigation on the structural and optical properties was conducted in lanthanum-substituted Ag(Nb0.80Ta0.20)O3 (ALNTx) thin films with La3+ concentrations of x = 0, 0.01, 0.02, and 0.03, prepared via chemical solution deposition process. X-ray diffraction confirmed the formation of a polycrystalline perovskite phase (orthorhombic, Pb21m) in all compositions, alongside minor Ag and Ag2O secondary-phases at low La levels. Raman spectroscopy revealed a progressive increase in the active vibrational modes with La doping, reaching up to 19 modes for the compositions with x = 0.02 and 0.03. In particular, the M1 band (at 108–110 cm-1) emerges only at these higher dopant levels, along with the progressive appearance of additional modes in the 550–950 cm-1 region (identified as M13–M19) as the La-content increases, indicating enhanced local structural distortion and NbO6 octahedral tilting. RBS analysis confirmed homogeneous stoichiometry and film thicknesses ranging from 4.4 × 1017 to 7.0 × 1017 atoms/cm2. Optical measurements revealed an indirect bandgap narrowing from 3.50 eV (undoped) to 2.81 eV (x = 0.02), driven by lattice distortion, local bonding changes and reduced Ag/La–O hybridization. The findings demonstrate that the La doping is an effective strategy for tuning the structural and optical properties of Ag(Nb,Ta)O3 thin films, making them attractive for integration into specialized optoelectronic applications, such as functional layers in tandem or multilayer energy devices.
M. Gabás, A. Landa-Cánovas, J. Santiso, I. Lombardero, I. García, N. Miyashita, Y. Okada, P. F. Palacios, C. Algora, «Microstructural effects of thermal annealing in GaInNAsSb epitaxial layers,» J. Alloys Compd. 10137, 182315 (2025)
A set of dilute nitride GaInNAsSb epitaxial layers, some of them submitted to a thermal treatment, has been studied in this work in order to elucidate the microstructural changes induced by annealing. Two semiconductor structures consisting in a GaInNAsSb layer with two different thicknesses, 0.2 and 1 μm, sandwiched between GaAs layers, were grown on GaAs substrates. Three pieces of each structure were studied: one was left as-grown, another one was submitted to a rapid thermal annealing (RTA), and the third one to a longer annealing in a Metal Organic Vapor Phase Epitaxy (MOVPE) reactor. The objective was to compare the GaInNAsSb layer microstructure before and after each thermal treatment, as a function of the dilute nitride layer thickness. The composition profile of the samples and their variations with annealing have been determined using secondary ion mass spectrometry. X-ray diffraction techniques have been used to explore each layer crystalline quality, the lattice mismatch, and the strain. High resolution transmission electron microscopy tools have allowed to establish a quantitative comparison among the samples in terms of misfit dislocations density. Our results indicate that the effect that each annealing has on the microstructure of these GaInNAsSb layers is dependent on the initial state of the as-grown samples. RTA has a limited effect on these layers, while the MOVPE annealing induces noticeable changes in its microstructure.
J. de Damborenea, A. Conde, G. P. Rodriguez-Donoso, F. Agulló-Rueda, and M. A. Arenas, «Thermal shock resistance of additive manufactured Inconel 718 by concentrated solar energy,» Sci. Rep. 15, 7557 (2025).
Concentrated Solar Power (CSP) is a powerful tool for simulating the extreme high-temperature conditions that metallic materials encounter. Using a vertical parabolic solar furnace, it was possible to perform heating and cooling cycles between 250 and 950 °C in approximately 250 s per cycle. This capability is particularly relevant for the development of solar receivers used in solar thermal plants. Additive Manufacturing (AM) offers the potential to create new compositions and geometries that can enhance the efficiency of these solar receivers. In this study, Ni-base superalloys—identified as suitable materials for high-temperature solar receivers—were produced using AM and tested in two conditions: as-built and after thermal treatment. These were compared with a forged reference alloy. The results revealed the formation of a protective oxide layer on the surface in all cases. However, the oxide layer on the samples fabricated by additive manufacturing appeared to be more compact and adherent compared to that formed on the reference alloy.
I. Solana, M. Dolores Ynsa, F. Agulló-Rueda, J. Sánchez-Prieto, D. Grojo, J. Siegel, M. Garcia-Lechuga, «Silicon amorphization responses by combined irradiations with MeV ion beams and ultrashort laser pulses,» Surf. Interfaces 69, 106772 (2025).
This work demonstrates a significant synergistic effect between MeV ion implantation and femtosecond laser irradiation in silicon amorphization. The achievable amorphization depth and the range of laser fluencies leading to amorphization is increased for implanted samples in comparison to pristine silicon. In Si(100) samples, prior to femtosecond laser irradiation (800 nm and 120 fs, or 1030 nm and 180 fs) ion-induced defects are produced with protons (0.6, 1 and 2 MeV) or Si-ions (2 MeV) at varying ion-irradiation fluences. Then, the investigated defects densities before laser irradiation range from low levels to levels approaching ion-induced amorphization (defects per atom, dpa, from 10-9 to 0.1). The optimal pre-conditioning for subsequent femtosecond laser-induced amorphization is found at a moderate defect density level, dpa =10-5. Additionally, it is shown that the achievable spatial resolution of the synergistic material amorphization is determined by the high resolution of the focused ion irradiation, suggesting a potential pathway for high-resolution patterning based on laser-assisted techniques. However, at high defect densities (dpa ≈ 0.1), the synergistic effect diminishes, and femtosecond laser irradiation instead reduces disorder, indicating a defect-annealing effect rather than further amorphization.
Seminar announcement: A New Microscope in the Neighborhood by Angel Landa
During the last decade new advances in electron microscopy are producing a revolution in transmission electron microscopy. This new developments in Transmission Electron Microscopy (TEM) and scanning TEM (STEM) are pushing the boundaries of nanoscale imaging and analysis, offering enhanced capabilities for materials science, biology, and other fields. Here are some key trends and recent advancements:
New developments in Scanning Transmission Electron Microscopy (STEM) are pushing the boundaries of nanoscale imaging and analysis, offering enhanced capabilities for materials science, biology, and other fields. Here are some key trends and recent advancements:
Advancements in Hardware and Software
In summary, the field of STEM is rapidly evolving with significant advancements in hardware, software, and methodologies. These new microscopes provide researchers with powerful tools to explore the nanoworld with unprecedented detail and enable breakthroughs in various scientific disciplines.
Osteosarcoma is a radioresistant cancer and proton therapy a promising radiation alternative to treat cancer with the advantage of high dose concentration in the tumor area. In this work, we propose the use of iodine substituted hydroxyapatite nanomaterials (IHAP) to use iodine (127I) as a proton radiation tracer giving access to range verification studies in mineralized tissues. For this purpose, the nanomaterials were synthesized at four iodine concentrations by hydrothermal synthesis. The material is characterized using different microstructural techniques to identify an optimal high iodine concentration and pure apatite phase nanomaterial. Finally, such pure IHAP powders were shaped and irradiated with proton beams of 6 and 10 MeV and their activation demonstrated through subsequent decay analysis. The materials could be integrated in phantom structures for the verification of doses and range of protons prior to animal testing and clinical proton therapy treatments of tumors located deep under combined soft and calcified tissue.
R. Magro, A. Muñoz-Noval, J. A. Briz Monago, J. R. Murias, A. Espinosa Rodríguez, L. M. Fraile, F. Agulló-Rueda, M. D. Ynsa, C. Tavares de Sousa, B. Cortés Llanos, G. M. García López, E. Nacher, V. García Tavora, N. Mont i Geli, A. Nerio, V. Valladolid Onecha, R. Pallás, A. Tarifeno-Saldivia, O. Tengblad, M. J. Manso Silvan and S. Viñals i Onsés, «Iodine substituted hydroxyapatite nanoparticles and activation of derived ceramics for range verification in proton therapy,» J. Mater. Chem. B , (2024).
In this study, we explore the morphology and orientation of molybdenum diselenide, a Van der Waals 2D material, through isothermal closed space vapor deposition on both pristine and laser-structured substrates. Laser structuring is conducted on dielectric (sapphire), semiconductor (silicon), and conductive (titanium nitride) substrates using ultrashort laser pulses, resulting in smooth topographic changes such as laser-induced periodic surface structures (LIPSS) or selective ablation. Scanning electron microscopy (SEM) reveals the pivotal role of surface structuring in the growth of out-of-plane MoSe2 nanosheets. This effect is particularly pronounced on crystalline substrates like sapphire and silicon, exhibiting in-plane growth on pristine substrates. Additionally, Raman spectroscopy not only confirms the vertical orientation of flakes on structured substrates but also highlights the presence of active edge sites by demonstrating an increased abundance of deposited material. Overall, our findings emphasize the controllability of directing the growth of MoSe2 flakes through appropriate pre-treatment of the substrate, with potential applications in various fields, including Surface-Enhanced Raman Scattering (SERS). Furthermore, the scalability, reproducibility, and applicability to any substrate make ultrashort laser structuration a highly promising general strategy for orienting 2D materials.
A. Fernández García, R. Ariza, J. Solis, F. Agulló-Rueda, M. Manso Silvan, M. Garcia-Lechuga, «Out-of-plane growth of 2D molybdenum diselenide nanosheets on ultrafast laser-structured substrates,» Appl. Surf. Sci. 160567 (2024).
