Selective Plasmonic Gas Sensing: H2, NO2, and CO Spectral Discrimination by a Single Au-CeO2 Nanocomposite Film

Journal Article · Tue Jun 05 00:00:00 EDT 2012 · Analytical Chemistry, 84(11):5025-5034

DOI:https://doi.org/10.1021/ac3006846· OSTI ID:1045097

Joy, N.; Nandasiri, Manjula I.; Rogers, Phillip H.; Jiang, Weilin; Varga, Tamas; Thevuthasan, Suntharampillai; Carpenter, Michael A.

A Au-CeO2 nanocomposite film has been investigated as a potential sensing element for high-temperature plasmonic sensing of H2, CO, and NO2 in an oxygen containing environment. The CeO2 thin film was deposited by molecular beam epitaxy (MBE) and Au was implanted into the as-grown film at an elevated temperature followed by high temperature annealing to form well-defined Au nanoclusters. The Au-CeO2 nanocomposite film was characterized by x-ray diffraction (XRD) and Rutherford backscattering spectrometry (RBS). For the gas sensing experiments, separate exposures to varying concentrations of H2, CO, and NO2 were performed at a temperature of 500°C in oxygen backgrounds of 5.0, 10, and ~21% O2. Changes in the localized surface plasmon resonance (LSPR) absorption peak were monitored during gas exposures and are believed to be the result of oxidation-reduction processes that fill or create oxygen vacancies in the CeO2. This process affects the LSPR peak position either by charge exchange with the Au nanoparticles or by changes in the dielectric constant surrounding the particles. Multivariate analysis was used to gauge the inherent selectivity of the film between the separate analytes. From principal component analysis (PCA), unique and identifiable responses were seen for each of the analytes. Linear discriminant analysis (LDA) was also used and showed separation between analytes as well as trends in gas concentration. Results indicate that the Au-CeO2 thin film is selective to O2, H2, CO, and NO2 in separate exposures. Combined with the observed stability over long exposure periods, the Au-CeO2 film shows good potential as an optical sensing element for harsh environmental conditions.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1045097
• Report Number(s): PNNL-SA-85244; 34895; KP1704020; TRN: US201214%%925
• Journal Information: Analytical Chemistry, 84(11):5025-5034, Vol. 84, Issue 11
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ABSORPTION
ANNEALING
CHARGE EXCHANGE
MOLECULAR BEAM EPITAXY
MULTIVARIATE ANALYSIS
OXYGEN
PERMITTIVITY
PLASMONS
RESONANCE
RUTHERFORD BACKSCATTERING SPECTROSCOPY
STABILITY
THIN FILMS
VACANCIES
X-RAY DIFFRACTION
Selective
Plasmonic
Gas
Sensing
H2
NO2
and
CO
Discrimination
Single
Au-CeO2
Nanocomposite
Film
Environmental Molecular Sciences Laboratory