skip to main content

Title: Effect of deuterium substitution for hydrogen in surface functionalisation of hydrophilic nanosilicon particles on their spectral and dynamic properties

Broadband femtosecond spectroscopy has been used to study two types of hydrophilic silicon nanoparticles: (1) photoluminescent, passivated with deuterium and oxidised in fully deuterated dimethyl sulphoxide, and (2) nonluminescent (control samples having a similar crystalline core), passivated with hydrogen and oxidised in dimethyl sulphoxide. We have found significant differences in ultrafast spectral – temporal induced absorption dynamics between the two types of nanoparticles in the energy range corresponding to their calculated band gap. The observed distinction is due to the considerably higher oxidation rate of silicon on the surface of the deuterated samples in comparison with the undeuterated ones and with the associated increase in the number of photoluminescence centres on the surface of the nanoparticles. In the samples containing self-trapped exciton (STE) energy states responsible for the photoluminescence in the red spectral region, carrier capture at these levels and carrier relaxation to the ground state have characteristic times in the femtosecond range. In the samples free of STE states, excited carriers relax to the conduction band bottom in a characteristic time of several picoseconds. (extreme light fields and their applications)
Authors:
;  [1] ;  [2] ;  [3] ;  [4] ;  [5]
  1. Institute of Spectroscopy, Russian Academy of Sciences, Troitsk, Moscow (Russian Federation)
  2. Department of Chemistry, M.V. Lomonosov Moscow State University, Moscow (Russian Federation)
  3. A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)
  4. Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka, Moscow Region (Russian Federation)
  5. M.V.Lomonosov Moscow State University of Fine Chemical Technologies, Moscow (Russian Federation)
Publication Date:
OSTI Identifier:
22395859
Resource Type:
Journal Article
Resource Relation:
Journal Name: Quantum Electronics (Woodbury, N.Y.); Journal Volume: 44; Journal Issue: 6; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; DEUTERIUM; EXCITONS; HYDROGEN; NANOPARTICLES; PASSIVATION; PHOTOLUMINESCENCE; SILICON; SPECTROSCOPY; TRAPPING