Assessment of compositional changes of carbonated cement pastes subjected to high temperatures using in-situ Raman mapping and XPS

Raman spectroscopy has grown to be one of the techniques of interest for the investigation of art objects. The approach has several advantageous properties, and the non-destructive character of the technique allowed it to be used for in situ investigations. However, compared with laboratory approaches, it would be useful to take advantage of the small spectral footprint of the technique, and use Raman spectroscopy to study the spatial distribution of different compounds. In this work, an in situ Raman mapping system is developed to be able to relate chemical information with its spatial distribution. Challenges for the development are discussed, including the need for stable positioning and proper data treatment. To avoid focusing problems, nineteenth century porcelain cards are used to test the system. This work focuses mainly on the post-processing of the large dataset which consists of four steps: (i) importing the data into the software; (ii) visualization of the dataset; (iii) extraction of the variables; and (iv) creation of a Raman image. It is shown that despite the challenging task of the development of the full in situ Raman mapping system, the first steps are very promising. This article is part of the themed issue ‘Raman spectroscopy in art and archaeology’.

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In situ Raman mapping for identifying transient solid forms

CrystEngComm ◽

10.1039/c5ce00008d ◽

2015 ◽

Vol 17 (28) ◽

pp. 5280-5287 ◽

Cited By ~ 6

Author(s):

Jagadeesh Babu Nanubolu ◽

Jonathan C. Burley

Keyword(s):

Phase Transformation ◽

Transient Phase ◽

Raman Mapping ◽

Surface Mapping ◽

Phase Form ◽

In Situ Raman

In situ Raman surface mapping on a trihydrate sample provides evidence for the existence of a transient phase X on the route to its stable anhydrous polymorph I. The phase transformation events are observed in the order trihydrate → transient phase → form I.

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In-situ Raman mapping during indentation

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/699/1/012027 ◽

2019 ◽

Vol 699 ◽

pp. 012027

Author(s):

I I Maslenikov ◽

A S Useinov

Keyword(s):

Raman Mapping ◽

In Situ Raman

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In situ REM imaging of surface processes on ceramic bulk crystals from 300 to 1670 K in a conventional TEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100087616 ◽

1991 ◽

Vol 49 ◽

pp. 660-661

Author(s):

Z. L. Wang ◽

J. Bentley

Keyword(s):

High Temperatures ◽

Image Resolution ◽

Atomic Processes ◽

Crystal Surfaces ◽

Beam Radiation ◽

Surface Areas ◽

Transmission Electron ◽

Reflection Electron Microscopy ◽

Gas Reactions

Studying the behavior of surfaces at high temperatures is of great importance for understanding the properties of ceramics and associated surface-gas reactions. Atomic processes occurring on bulk crystal surfaces at high temperatures can be recorded by reflection electron microscopy (REM) in a conventional transmission electron microscope (TEM) with relatively high resolution, because REM is especially sensitive to atomic-height steps.Improved REM image resolution with a FEG: Cleaved surfaces of a-alumina (012) exhibit atomic flatness with steps of height about 5 Å, determined by reference to a screw (or near screw) dislocation with a presumed Burgers vector of b = (1/3)<012> (see Fig. 1). Steps of heights less than about 0.8 Å can be clearly resolved only with a field emission gun (FEG) (Fig. 2). The small steps are formed by the surface oscillating between the closely packed O and Al stacking layers. The bands of dark contrast (Fig. 2b) are the result of beam radiation damage to surface areas initially terminated with O ions.

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“In-Situ Raman Spectroscopy of Electronic Processes in Fullerene Thin Films

MRS Proceedings ◽

10.1557/proc-725-p10.8 ◽

2002 ◽

Vol 725 ◽

Author(s):

S.B. Phelan ◽

B.S. O'Connell ◽

G. Farrell ◽

G. Chambers ◽

H.J. Byrne

Keyword(s):

Thin Film ◽

Indium Tin Oxide ◽

Low Temperatures ◽

In Situ Raman Spectroscopy ◽

State Reduction ◽

In Situ Raman ◽

Linear Behavior ◽

Current Voltage ◽

Solid State Reduction

AbstractThe current voltage characteristics of C60 thin film sandwich structures fabricated by vacuum deposition on indium tin oxide (ITO) with an aluminium top electrode are presented and discussed. A strongly non-linear behavior and a sharp increase in the device conductivity was observed at relatively low voltages (∼2V), at both room and low temperatures (20K). At room temperature the system is seen to collapse, and in situ Raman measurements indicate a solid state reduction of the fullerene thin film to form a polymeric state. The high conductivity state was seen to be stable at elevated voltages and low temperatures. This state is seen to be reversible with the application of high voltages. At these high voltages the C60 film was seen to sporadically emit white light at randomly localized points analogous to the much documented Electroluminescence in single crystals.

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