Thermal evaporation and x-ray photostability of dodecyl-passivated silicon nanoparticles

Abstract

X-ray photoelectron spectroscopy (XPS) and x-ray absorption spectroscopy have been used to study the makeup of thin films of 6.5 nm diameter dodecyl-capped silicon nanoparticles (SiNPs) formed in a one-pot synthesis method of micelle reduction. Thermostability measurements show the SiNPs undergo thermal desorption at ∼240 °C, a higher temperature than for SiNPs capped by shorter hydrocarbon layers owing to the greater size of the nanoparticle system in this case. Suspensions of SiNPs are found to evaporate in a UHV environment intact with the hydrocarbon passivating layer preserved and form thin films which are visualized with microimaging FTIR spectroscopy. The stability of the capping layer within thick SiNP films under extended exposure (up to 2160 s) to 140 eV photons has been examined where XPS spectra show the breakdown of the passivating layer allowing the underlying silicon core to undergo subsequent oxidation.

Amine-terminated nanoparticle films: pattern deposition by a simple nanostencilling technique and stability studies under X-ray irradiation

“…43,44 Here we have developed this technique to prepare thin films through nanostencilling in a manner which allows them to be studied by spatially-resolved FTIR micro-mapping methods. 45 The results highlight the potential of this emerging technique in characterizing nanoscale structures. The second part of this work concerns the behaviour of thicker films formed by dropcast methods.…”