Solar induced growth of silver nanocrystals

TL;DR

This study investigates how solar irradiation influences the growth and shape of silver nanocrystals, revealing growth patterns consistent with Ostwald ripening but not reaching steady-state distributions, relevant for solar cell light harvesting.

Contribution

It provides experimental evidence of solar-induced growth of silver nanocrystals and compares the process to Ostwald ripening models, highlighting transient state behavior.

Findings

Nanocrystals grow under solar irradiation, reaching up to 638 nm in diameter.

Size distribution remains approximately log-normal during growth.

Growth aligns with Ostwald ripening predictions but does not reach steady state.

Abstract

The effect of solar irradiation on plasmonic silver nanocrystals has been investigated using Transmission Electron Microscopy and size distribution analysis, in the context of solar cell applications for light harvesting. Starting from an initial collection of spherical nanocrystals on a carbon film whose sizes are log-normally distributed, solar irradiation causes the nanocrystals to grow, with one particle reaching a diameter of 638 nm after four hours of irradiation. In addition some of the larger particles lose their spherical shape. The average nanocrystal diameter was found to grow as predicted by the Ostwald ripening model, taking into account the range of area fractions of the samples. The size distribution stays approximately log-normal and does not reach one of the steady-state size distributions predicted by the Ostwald ripening model. This might be explained by the system being in a transient state.