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

DOI: 10.1088/0022-3727/45/35/355303

Authors: Paul Coxon (University of East Anglia) , Shane Ashby (University of East Anglia) , Mark Frogley (Diamond Light Source) , Yimin Chao (University of East Anglia)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Journal Of Physics D: Applied Physics , VOL 45 (35)

State: Published (Approved)
Published: September 2012
Diamond Proposal Number(s): 7065

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.

Journal Keywords: Absorption Spectroscopy; Breakdown; Desorption; Hydrocarbons; Infrared Spectra; Layers; Nanostructures; Oxidation; Photons; Silicon; Suspensions; Synthesis; Thin Films; X Radiation; X-Ray Photoelectron Spectroscopy; X-Ray Spectroscopy

Subject Areas: Materials, Chemistry


Instruments: B22-Multimode InfraRed imaging And Microspectroscopy

Other Facilities: Maxlab