Understanding the ion-induced elongation of silver nanoparticles embedded in silica

Abstract

In this work we have studied the elongation of silver nanoparticles irradiated with 40 MeV Bromine ions by means of in situ optical measurements, transmission electron microscopy and molecular dynamics simulations. The localized surface plasmon resonance of silver nanoparticles has a strong dependence on the particle shape and size, which allowed us to obtain the geometrical parameters with remarkable accuracy by means of a fit of the optical spectra. Optical results have been compared with transmission electron microscopy images and molecular dynamics simulations and the agreement is excellent in both cases. An important advantage of in situ measurements is that they yield an extremely detailed information of the full elongation kinetics. Final nanoparticle elongation depends on a complex competition between single-ion deformation, Ostwald ripening and dissolution. Building and validating theoretical models with the data reported in this work should be easier than with the information previously available, due to the unprecedented level of kinetic details obtained from the in situ measurements.

Recent Advances in Hybrid Optical Materials: Integrating Nanoparticles within a Glass Matrix

“…This is in accordance with MD simulations (concerning SHIs‐induced elongation of Au NPs in silica), indicating that the elongation is caused by an anisotropic thermal expansion of molten NPs within the latent tracks produced by the imposed ions . In a recent, more comprehensive work which combines in situ optical monitoring ( Figure a,b), Transmission electron microscope (TEM) imaging analysis (Figure c), and MD simulations, the authors deduced that the elongation of metal NP (e.g., Ag NPs in silica) via SHIs involves a complex competition between single‐ion deformation, Ostwald ripening, and particles dissolution . Although the complete physical mechanism involved in this sphere‐to‐rod transformation has not been established, the extensive research has enabled semimodels for phenomenological interpretation and high‐level control of specific characteristics .…”

Electronic heat transport versus atomic heating in irradiated short metallic nanowires

“…a decrease [90]. For nonhomogeneous systems, like a matrix with nanoparticles [91], these values could change dramatically from one material to another. Finally, e-ph coupling could be applied to phonon branches, and this would change temperature evolution in the sample [92].…”

Estudios atomísticos de la respuesta a la irradiación de materiales ópticos con aplicación en plantas de fusión nuclear

“… Análisis de la elongación de las nanopartículas metálicas embebidas dentro de la sílice y la variación de propiedades microscópicas, 92 que detallaremos en el Capítulo 7.…”

“…Al alcanzar cierto número de impactos la nanopartícula es destruida, reconstruyéndose al poco en nuevas esferas. 92 Los potenciales de interacción entre la nanopartícula y la matriz deben; por tanto, imponer las condiciones descritas anteriormente. Esto es, trabajar con distintos tamaños de nanopartículas, para intentar observar el efecto de tamaño.…”

“…El área cian representa, aproximadamente, la región de "elongación pura" que será utilizada para comparar con los resultados de MD. 92 En resumen, la elongación de las nanopartículas (al menos en este régimen de irradiación) no es un proceso de impacto único. Es una compleja competición entre deformación, disolución y maduración de Ostwald.…”