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Study and characterization of porous copper oxide produced by electrochemical anodization for radiometric heat absorber.

Ben Salem S, Achour ZB, Thamri K, Touayar O - Nanoscale Res Lett (2014)

Bottom Line: Using the 'mirage effect' technique, the obtained Cu2O diffusivity and thermal conductivity are respectively equal to (11.5 ± 0.5) 10 to 7 m(2) s(-1) and (370 ± 20) Wm(-1) K(-1).The results of the optical and thermal studies dictate the choice of the cavity design.So the absorption of the surface becomes closely near 0.999999.

View Article: PubMed Central - HTML - PubMed

Affiliation: Research Laboratory Materials, Measurement and Applications, Institut National des Sciences Appliquées et de Technologie, INSAT, BP676, 1080 Tunis Cedex, Tunisia.

ABSTRACT
The aim of this work is to optimize the different parameters for realization of an absorbing cavity to measure the incident absolute laser energy. Electrochemical oxidation is the background process that allowed the copper blackening. A study of the blackened surface quality was undertaken using atomic force microscopy (AFM) analysis and ultraviolet-visible-infrared spectrophotometry using a Shimadzu spectrophotometer. A two-dimensional and three-dimensional visualization by AFM of the formed oxide coating showed that the copper surfaces became porous after electrochemical etching with different roughness. This aspect is becoming more and more important with decreasing current density anodization. In a 2 mol L(-1) of NaOH solution, at a temperature of 90°C, and using a 16 mA cm(2) constant density current, the copper oxide formed has a reflectivity of around 3% in the spectral range between 300 and 1,800 nm. Using the 'mirage effect' technique, the obtained Cu2O diffusivity and thermal conductivity are respectively equal to (11.5 ± 0.5) 10 to 7 m(2) s(-1) and (370 ± 20) Wm(-1) K(-1). This allows us to consider that our Cu2O coating is a good thermal conductor. The results of the optical and thermal studies dictate the choice of the cavity design. The absorbing cavity is a hollow cylinder machined to its base at an angle of 30°. If the included angle of the plane is 30° and the interior surface gives specular reflection, an incoming ray parallel to the axis will undergo five reflections before exit. So the absorption of the surface becomes closely near 0.999999.

No MeSH data available.


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Design of the cryogenic radiometer.
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Figure 11: Design of the cryogenic radiometer.

Mentions: When we choose an angle α of 30°, we obtain five reflections of the incident beam before escaping the cavity. Knowing that the inner surface have a reflectivity coefficient ρ at about 3%, the total coefficient of absorbed radiation before exit (1 - ρn) is equal to 0.999999. Compared with the international references for absolute laser power measurements, our cavity can be considered as a good absorbing cavity [3,13-15].Our cryogenic radiometer is an electrical substitution detector operating at liquid nitrogen temperature (77 K). A schematic side viewing of our cryogenic radiometer is shown in Figure 11. The radiometer is designed specifically to accept collimated laser beam. The window port is tilted at Brewster's angle to minimize reflective losses when the laser beam is linearly polarized. The radiation-receiving cavity is a horizontal cylinder which is constructed from a copper tube containing an inclined plane. This cavity is thermally linked to the nitrogen liquid Dewar, and a black copper oxide makes its inner surface.


Study and characterization of porous copper oxide produced by electrochemical anodization for radiometric heat absorber.

Ben Salem S, Achour ZB, Thamri K, Touayar O - Nanoscale Res Lett (2014)

Design of the cryogenic radiometer.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4209770&req=5

Figure 11: Design of the cryogenic radiometer.
Mentions: When we choose an angle α of 30°, we obtain five reflections of the incident beam before escaping the cavity. Knowing that the inner surface have a reflectivity coefficient ρ at about 3%, the total coefficient of absorbed radiation before exit (1 - ρn) is equal to 0.999999. Compared with the international references for absolute laser power measurements, our cavity can be considered as a good absorbing cavity [3,13-15].Our cryogenic radiometer is an electrical substitution detector operating at liquid nitrogen temperature (77 K). A schematic side viewing of our cryogenic radiometer is shown in Figure 11. The radiometer is designed specifically to accept collimated laser beam. The window port is tilted at Brewster's angle to minimize reflective losses when the laser beam is linearly polarized. The radiation-receiving cavity is a horizontal cylinder which is constructed from a copper tube containing an inclined plane. This cavity is thermally linked to the nitrogen liquid Dewar, and a black copper oxide makes its inner surface.

Bottom Line: Using the 'mirage effect' technique, the obtained Cu2O diffusivity and thermal conductivity are respectively equal to (11.5 ± 0.5) 10 to 7 m(2) s(-1) and (370 ± 20) Wm(-1) K(-1).The results of the optical and thermal studies dictate the choice of the cavity design.So the absorption of the surface becomes closely near 0.999999.

View Article: PubMed Central - HTML - PubMed

Affiliation: Research Laboratory Materials, Measurement and Applications, Institut National des Sciences Appliquées et de Technologie, INSAT, BP676, 1080 Tunis Cedex, Tunisia.

ABSTRACT
The aim of this work is to optimize the different parameters for realization of an absorbing cavity to measure the incident absolute laser energy. Electrochemical oxidation is the background process that allowed the copper blackening. A study of the blackened surface quality was undertaken using atomic force microscopy (AFM) analysis and ultraviolet-visible-infrared spectrophotometry using a Shimadzu spectrophotometer. A two-dimensional and three-dimensional visualization by AFM of the formed oxide coating showed that the copper surfaces became porous after electrochemical etching with different roughness. This aspect is becoming more and more important with decreasing current density anodization. In a 2 mol L(-1) of NaOH solution, at a temperature of 90°C, and using a 16 mA cm(2) constant density current, the copper oxide formed has a reflectivity of around 3% in the spectral range between 300 and 1,800 nm. Using the 'mirage effect' technique, the obtained Cu2O diffusivity and thermal conductivity are respectively equal to (11.5 ± 0.5) 10 to 7 m(2) s(-1) and (370 ± 20) Wm(-1) K(-1). This allows us to consider that our Cu2O coating is a good thermal conductor. The results of the optical and thermal studies dictate the choice of the cavity design. The absorbing cavity is a hollow cylinder machined to its base at an angle of 30°. If the included angle of the plane is 30° and the interior surface gives specular reflection, an incoming ray parallel to the axis will undergo five reflections before exit. So the absorption of the surface becomes closely near 0.999999.

No MeSH data available.


Related in: MedlinePlus