13 research outputs found
Extension of Rietveld Refinement for Benchtop Powder XRD Analysis of Ultrasmall Supported Nanoparticles
We
present a method for characterizing ultrasmall (<2 nm) supported
crystallites with benchtop XRD. Central to the method is an understanding
of the intensity effects at play; these intensity effects and their
corrections are discussed in depth. Background subtractionlong
considered one of the main barriers to ultrasmall crystal characterizationis
solved by correcting the diffractogram of a separately measured support
for the relevant intensity effects. Rietveld refinement is demonstrated
to be an adequate analysis method for the general characterization
of simple nanosystems. A 4.8% Pt/SiO2 sample (1.3 nm, volume-weighted
average) is used as a case study; it is found that the Pt spontaneously
oxidizes under ambient conditions and consists of a metallic core
surrounded by a PtO2 shell. Both phases have average dimensions
smaller than 1 nm. The XRD results also suggest lattice expansion
of the Pt core as compared to bulk Pt
Extension of Rietveld Refinement for Benchtop Powder XRD Analysis of Ultrasmall Supported Nanoparticles
We
present a method for characterizing ultrasmall (<2 nm) supported
crystallites with benchtop XRD. Central to the method is an understanding
of the intensity effects at play; these intensity effects and their
corrections are discussed in depth. Background subtractionlong
considered one of the main barriers to ultrasmall crystal characterizationis
solved by correcting the diffractogram of a separately measured support
for the relevant intensity effects. Rietveld refinement is demonstrated
to be an adequate analysis method for the general characterization
of simple nanosystems. A 4.8% Pt/SiO2 sample (1.3 nm, volume-weighted
average) is used as a case study; it is found that the Pt spontaneously
oxidizes under ambient conditions and consists of a metallic core
surrounded by a PtO2 shell. Both phases have average dimensions
smaller than 1 nm. The XRD results also suggest lattice expansion
of the Pt core as compared to bulk Pt
Extension of Rietveld Refinement for Benchtop Powder XRD Analysis of Ultrasmall Supported Nanoparticles
We
present a method for characterizing ultrasmall (<2 nm) supported
crystallites with benchtop XRD. Central to the method is an understanding
of the intensity effects at play; these intensity effects and their
corrections are discussed in depth. Background subtractionlong
considered one of the main barriers to ultrasmall crystal characterizationis
solved by correcting the diffractogram of a separately measured support
for the relevant intensity effects. Rietveld refinement is demonstrated
to be an adequate analysis method for the general characterization
of simple nanosystems. A 4.8% Pt/SiO2 sample (1.3 nm, volume-weighted
average) is used as a case study; it is found that the Pt spontaneously
oxidizes under ambient conditions and consists of a metallic core
surrounded by a PtO2 shell. Both phases have average dimensions
smaller than 1 nm. The XRD results also suggest lattice expansion
of the Pt core as compared to bulk Pt
Extension of Rietveld Refinement for Benchtop Powder XRD Analysis of Ultrasmall Supported Nanoparticles
We
present a method for characterizing ultrasmall (<2 nm) supported
crystallites with benchtop XRD. Central to the method is an understanding
of the intensity effects at play; these intensity effects and their
corrections are discussed in depth. Background subtractionlong
considered one of the main barriers to ultrasmall crystal characterizationis
solved by correcting the diffractogram of a separately measured support
for the relevant intensity effects. Rietveld refinement is demonstrated
to be an adequate analysis method for the general characterization
of simple nanosystems. A 4.8% Pt/SiO2 sample (1.3 nm, volume-weighted
average) is used as a case study; it is found that the Pt spontaneously
oxidizes under ambient conditions and consists of a metallic core
surrounded by a PtO2 shell. Both phases have average dimensions
smaller than 1 nm. The XRD results also suggest lattice expansion
of the Pt core as compared to bulk Pt
Atomic Layer Deposition of Transparent and Conducting p‑Type Cu(I) Incorporated ZnS Thin Films: Unravelling the Role of Compositional Heterogeneity on Optical and Carrier Transport Properties
Optically transparent
and highly conducting p-type Cu(I) incorporated
ZnS (Cu:ZnS) films are deposited by stacking individual layers of
CuS and ZnS using atomic layer deposition. The deposition chemistry
and growth mechanism are studied by in situ quartz crystal microbalance.
Compositional disorder in atomic scale is observed with increasing
Cu incorporation in the films that results in systematic decrease
in the optical transmittance in the visible spectrum. Again the conductivity
also emphatically depends on the volume fraction of phase-segregated
conducting covellite phase. An illustrious correlation prevailing
the interplay between the optical transparency and the charge transport
mechanism is established. The hole transport mechanism that indicates
insulator-to-metal transition with increasing Cu incorporation in
the composite is explained in terms of an inhomogeneously disordered
system. Under optimized conditions, the material having moderately
high optical transmission with degenerate carrier concentration lies
exactly at the confluence between the metallic and insulating regime.
The lowest resistivity that is obtained here (1.3 × 10<sup>–3</sup> Ω cm) with >90% (after reflection correction) transmission
is highly comparable to the best ones that are reported in the field
and probably analogous to the commercially available n-type transparent
conductors
Extension of Rietveld Refinement for Benchtop Powder XRD Analysis of Ultrasmall Supported Nanoparticles
We
present a method for characterizing ultrasmall (<2 nm) supported
crystallites with benchtop XRD. Central to the method is an understanding
of the intensity effects at play; these intensity effects and their
corrections are discussed in depth. Background subtractionlong
considered one of the main barriers to ultrasmall crystal characterizationis
solved by correcting the diffractogram of a separately measured support
for the relevant intensity effects. Rietveld refinement is demonstrated
to be an adequate analysis method for the general characterization
of simple nanosystems. A 4.8% Pt/SiO2 sample (1.3 nm, volume-weighted
average) is used as a case study; it is found that the Pt spontaneously
oxidizes under ambient conditions and consists of a metallic core
surrounded by a PtO2 shell. Both phases have average dimensions
smaller than 1 nm. The XRD results also suggest lattice expansion
of the Pt core as compared to bulk Pt
Extension of Rietveld Refinement for Benchtop Powder XRD Analysis of Ultrasmall Supported Nanoparticles
We
present a method for characterizing ultrasmall (<2 nm) supported
crystallites with benchtop XRD. Central to the method is an understanding
of the intensity effects at play; these intensity effects and their
corrections are discussed in depth. Background subtractionlong
considered one of the main barriers to ultrasmall crystal characterizationis
solved by correcting the diffractogram of a separately measured support
for the relevant intensity effects. Rietveld refinement is demonstrated
to be an adequate analysis method for the general characterization
of simple nanosystems. A 4.8% Pt/SiO2 sample (1.3 nm, volume-weighted
average) is used as a case study; it is found that the Pt spontaneously
oxidizes under ambient conditions and consists of a metallic core
surrounded by a PtO2 shell. Both phases have average dimensions
smaller than 1 nm. The XRD results also suggest lattice expansion
of the Pt core as compared to bulk Pt
Extension of Rietveld Refinement for Benchtop Powder XRD Analysis of Ultrasmall Supported Nanoparticles
We
present a method for characterizing ultrasmall (<2 nm) supported
crystallites with benchtop XRD. Central to the method is an understanding
of the intensity effects at play; these intensity effects and their
corrections are discussed in depth. Background subtractionlong
considered one of the main barriers to ultrasmall crystal characterizationis
solved by correcting the diffractogram of a separately measured support
for the relevant intensity effects. Rietveld refinement is demonstrated
to be an adequate analysis method for the general characterization
of simple nanosystems. A 4.8% Pt/SiO2 sample (1.3 nm, volume-weighted
average) is used as a case study; it is found that the Pt spontaneously
oxidizes under ambient conditions and consists of a metallic core
surrounded by a PtO2 shell. Both phases have average dimensions
smaller than 1 nm. The XRD results also suggest lattice expansion
of the Pt core as compared to bulk Pt
Extension of Rietveld Refinement for Benchtop Powder XRD Analysis of Ultrasmall Supported Nanoparticles
We
present a method for characterizing ultrasmall (<2 nm) supported
crystallites with benchtop XRD. Central to the method is an understanding
of the intensity effects at play; these intensity effects and their
corrections are discussed in depth. Background subtractionlong
considered one of the main barriers to ultrasmall crystal characterizationis
solved by correcting the diffractogram of a separately measured support
for the relevant intensity effects. Rietveld refinement is demonstrated
to be an adequate analysis method for the general characterization
of simple nanosystems. A 4.8% Pt/SiO2 sample (1.3 nm, volume-weighted
average) is used as a case study; it is found that the Pt spontaneously
oxidizes under ambient conditions and consists of a metallic core
surrounded by a PtO2 shell. Both phases have average dimensions
smaller than 1 nm. The XRD results also suggest lattice expansion
of the Pt core as compared to bulk Pt
Extension of Rietveld Refinement for Benchtop Powder XRD Analysis of Ultrasmall Supported Nanoparticles
We
present a method for characterizing ultrasmall (<2 nm) supported
crystallites with benchtop XRD. Central to the method is an understanding
of the intensity effects at play; these intensity effects and their
corrections are discussed in depth. Background subtractionlong
considered one of the main barriers to ultrasmall crystal characterizationis
solved by correcting the diffractogram of a separately measured support
for the relevant intensity effects. Rietveld refinement is demonstrated
to be an adequate analysis method for the general characterization
of simple nanosystems. A 4.8% Pt/SiO2 sample (1.3 nm, volume-weighted
average) is used as a case study; it is found that the Pt spontaneously
oxidizes under ambient conditions and consists of a metallic core
surrounded by a PtO2 shell. Both phases have average dimensions
smaller than 1 nm. The XRD results also suggest lattice expansion
of the Pt core as compared to bulk Pt
