Carbon Nanotubes Based Black Absorbing Coatings for Pyroelectric and Other Thermal Detector Application
The study of optical and thermophysical characteristics of the absorbing coatings (AC) for sensitive elements of pyroelectric detectors of radiation based on carbon nanotubes paste (CNTP-black) is performed in comparison with those AC formed from gold disperse layer (Au-black) and dielectric lacq...
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Інститут металофізики ім. Г.В. Курдюмова НАН України
2009
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| Назва видання: | Наносистеми, наноматеріали, нанотехнології |
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| Цитувати: | Carbon Nanotubes Based Black Absorbing Coatings for Pyroelectric and Other Thermal Detector Application / S.L. Bravina, N.V. Morozovsky, G.I. Dovbeshko, O.M. Fesenko, E.D. Obraztsova // Наносистеми, наноматеріали, нанотехнології: Зб. наук. пр. — К.: РВВ ІМФ, 2009. — Т. 7, № 1. — С. 137-145. — Бібліогр.: 22 назв. — англ. |
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irk-123456789-763422015-02-10T03:02:43Z Carbon Nanotubes Based Black Absorbing Coatings for Pyroelectric and Other Thermal Detector Application Bravina, S.L. Morozovsky, N.V. Dovbeshko, G.I. Fesenko, O.M. Obraztsova, E.D. The study of optical and thermophysical characteristics of the absorbing coatings (AC) for sensitive elements of pyroelectric detectors of radiation based on carbon nanotubes paste (CNTP-black) is performed in comparison with those AC formed from gold disperse layer (Au-black) and dielectric lacquer paint (DLP-black). The spectral dependences of reflectance and absorbance of CNTP-black, Au-black and DLP-black in IR-spectrum range 2.5—25 μm are presented. By photothermomodulation method, the frequency spectra of pyroelectric response amplitude and phase are obtained. The estimation of thermal diffusivity values of the investigated blacks as AC for sensitive elements of pyroelectric detectors is performed in situ. Prospects of using CNTP-black based AC for pyroelectric and other thermal detector applications are shown. Виконано порівняльні дослідження оптичних і теплофізичних характеристик вбирних покриттів (ВП) для чутливих елементів піроелектричних приймачів випромінення на основі пасти з вуглецевих нанорурок (ВНР- пасти), золотої черні (Au-черні) і діелектричної лакофарбової черні (ДЛФ-черні). Представлено спектральні залежності ІЧ-відбивання і вбирання ВНР-черні, Au-черні і ДЛФ-черні в інтервалі довжин хвиль 2,5—25 мкм. За допомогою фототермомодуляційнної методи одержано частотні спектри амплітуди і фази піроелектричного відгуку. Визначено «у місці знаходження» величини температуропровідности досліджуваних типів черні як ВП для чутливих елементів піроелектричних приймачів випромінен- ня. Показано перспективність використання ВП на основі черні з ВНР- пасти для піроелектричних й інших теплових приймачів випромінення. Проведены сравнительные исследования оптических и теплофизических характеристик поглощающих покрытий (ПП) для чувствительных элементов пироэлектрических приемников излучения на основе пасты из углеродных нанотрубок (УНТ-пасты), золотой черни (Au-черни) и диэлектрической лакокрасочной черни (ДЛК-черни). Представлены спектральные зависимости ИК-отражения и поглощения УНТ-черни, Au- черни и ДЛК-черни в интервале длин волн 2,5—25 мкм. С помощью фототермомодуляционного метода получены частотные спектры амплитуды и фазы пироэлектрического отклика. Проведено определение «в месте нахождения» величины температуропроводности исследуемых типов черни как ПП для чувствительных элементов пироэлектрических приемников излучения. Показана перспективность использования ПП на основе черни из УНТ-пасты для пироэлектрических и других тепловых приемников излучения. 2009 Article Carbon Nanotubes Based Black Absorbing Coatings for Pyroelectric and Other Thermal Detector Application / S.L. Bravina, N.V. Morozovsky, G.I. Dovbeshko, O.M. Fesenko, E.D. Obraztsova // Наносистеми, наноматеріали, нанотехнології: Зб. наук. пр. — К.: РВВ ІМФ, 2009. — Т. 7, № 1. — С. 137-145. — Бібліогр.: 22 назв. — англ. 1816-5230 PACS numbers: 61.48.De, 77.70.+a, 78.20.Ci, 78.67.Ch, 81.05.ub, 81.07.De http://dspace.nbuv.gov.ua/handle/123456789/76342 en Наносистеми, наноматеріали, нанотехнології Інститут металофізики ім. Г.В. Курдюмова НАН України |
| institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| collection |
DSpace DC |
| language |
English |
| description |
The study of optical and thermophysical characteristics of the absorbing
coatings (AC) for sensitive elements of pyroelectric detectors of radiation
based on carbon nanotubes paste (CNTP-black) is performed in comparison
with those AC formed from gold disperse layer (Au-black) and dielectric lacquer
paint (DLP-black). The spectral dependences of reflectance and absorbance
of CNTP-black, Au-black and DLP-black in IR-spectrum range 2.5—25
μm are presented. By photothermomodulation method, the frequency spectra
of pyroelectric response amplitude and phase are obtained. The estimation of
thermal diffusivity values of the investigated blacks as AC for sensitive elements
of pyroelectric detectors is performed in situ. Prospects of using
CNTP-black based AC for pyroelectric and other thermal detector applications
are shown. |
| format |
Article |
| author |
Bravina, S.L. Morozovsky, N.V. Dovbeshko, G.I. Fesenko, O.M. Obraztsova, E.D. |
| spellingShingle |
Bravina, S.L. Morozovsky, N.V. Dovbeshko, G.I. Fesenko, O.M. Obraztsova, E.D. Carbon Nanotubes Based Black Absorbing Coatings for Pyroelectric and Other Thermal Detector Application Наносистеми, наноматеріали, нанотехнології |
| author_facet |
Bravina, S.L. Morozovsky, N.V. Dovbeshko, G.I. Fesenko, O.M. Obraztsova, E.D. |
| author_sort |
Bravina, S.L. |
| title |
Carbon Nanotubes Based Black Absorbing Coatings for Pyroelectric and Other Thermal Detector Application |
| title_short |
Carbon Nanotubes Based Black Absorbing Coatings for Pyroelectric and Other Thermal Detector Application |
| title_full |
Carbon Nanotubes Based Black Absorbing Coatings for Pyroelectric and Other Thermal Detector Application |
| title_fullStr |
Carbon Nanotubes Based Black Absorbing Coatings for Pyroelectric and Other Thermal Detector Application |
| title_full_unstemmed |
Carbon Nanotubes Based Black Absorbing Coatings for Pyroelectric and Other Thermal Detector Application |
| title_sort |
carbon nanotubes based black absorbing coatings for pyroelectric and other thermal detector application |
| publisher |
Інститут металофізики ім. Г.В. Курдюмова НАН України |
| publishDate |
2009 |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/76342 |
| citation_txt |
Carbon Nanotubes Based Black Absorbing Coatings
for Pyroelectric and Other Thermal Detector Application / S.L. Bravina, N.V. Morozovsky, G.I. Dovbeshko, O.M. Fesenko, E.D. Obraztsova // Наносистеми, наноматеріали, нанотехнології: Зб. наук. пр. — К.: РВВ ІМФ, 2009. — Т. 7, № 1. — С. 137-145. — Бібліогр.: 22 назв. — англ. |
| series |
Наносистеми, наноматеріали, нанотехнології |
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2025-07-06T00:48:01Z |
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137
PACS numbers: 61.48.De, 77.70.+a, 78.20.Ci, 78.67.Ch, 81.05.ub, 81.07.De
Carbon Nanotubes Based Black Absorbing Coatings
for Pyroelectric and Other Thermal Detector Application
S. L. Bravina, N. V. Morozovsky, G. I. Dovbeshko, O. M. Fesenko,
and E. D. Obraztsova*
Institute of Physics, N.A.S.U.,
Nauky Prosp., 46,
03028 Kyyiv, Ukraine
*Natural Science Centre of A. M. Prokhorov Institute of General Physics, R.A.S.,
Vavilov Str., 38,
119991 Moscow, Russia
The study of optical and thermophysical characteristics of the absorbing
coatings (AC) for sensitive elements of pyroelectric detectors of radiation
based on carbon nanotubes paste (CNTP-black) is performed in comparison
with those AC formed from gold disperse layer (Au-black) and dielectric lac-
quer paint (DLP-black). The spectral dependences of reflectance and absorb-
ance of CNTP-black, Au-black and DLP-black in IR-spectrum range 2.5—25
μm are presented. By photothermomodulation method, the frequency spectra
of pyroelectric response amplitude and phase are obtained. The estimation of
thermal diffusivity values of the investigated blacks as AC for sensitive ele-
ments of pyroelectric detectors is performed in situ. Prospects of using
CNTP-black based AC for pyroelectric and other thermal detector applica-
tions are shown.
Виконано порівняльні дослідження оптичних і теплофізичних характе-
ристик вбирних покриттів (ВП) для чутливих елементів піроелектричних
приймачів випромінення на основі пасти з вуглецевих нанорурок (ВНР-
пасти), золотої черні (Au-черні) і діелектричної лакофарбової черні (ДЛФ-
черні). Представлено спектральні залежності ІЧ-відбивання і вбирання
ВНР-черні, Au-черні і ДЛФ-черні в інтервалі довжин хвиль 2,5—25 мкм.
За допомогою фототермомодуляційнної методи одержано частотні спект-
ри амплітуди і фази піроелектричного відгуку. Визначено «у місці знахо-
дження» величини температуропровідности досліджуваних типів черні
як ВП для чутливих елементів піроелектричних приймачів випромінен-
ня. Показано перспективність використання ВП на основі черні з ВНР-
пасти для піроелектричних й інших теплових приймачів випромінення.
Наносистеми, наноматеріали, нанотехнології
Nanosystems, Nanomaterials, Nanotechnologies
2009, т. 7, № 1, сс. 137—145
© 2009 ІМФ (Інститут металофізики
ім. Г. В. Курдюмова НАН України)
Надруковано в Україні.
Фотокопіювання дозволено
тільки відповідно до ліцензії
138 S. L. BRAVINA, N. V. MOROZOVSKY, G. I. DOVBESHKO et al.
Проведены сравнительные исследования оптических и теплофизических
характеристик поглощающих покрытий (ПП) для чувствительных эле-
ментов пироэлектрических приемников излучения на основе пасты из
углеродных нанотрубок (УНТ-пасты), золотой черни (Au-черни) и ди-
электрической лакокрасочной черни (ДЛК-черни). Представлены спек-
тральные зависимости ИК-отражения и поглощения УНТ-черни, Au-
черни и ДЛК-черни в интервале длин волн 2,5—25 мкм. С помощью фото-
термомодуляционного метода получены частотные спектры амплитуды и
фазы пироэлектрического отклика. Проведено определение «в месте на-
хождения» величины температуропроводности исследуемых типов черни
как ПП для чувствительных элементов пироэлектрических приемников
излучения. Показана перспективность использования ПП на основе чер-
ни из УНТ-пасты для пироэлектрических и других тепловых приемников
излучения.
Key words: thermal detectors, absorbing coatings, metal black, paint black,
carbon nanotubes black.
(Received November 28, 2007)
1. INTRODUCTION
Application field of one of the most important class of thermal detec-
tors, pyroelectric detectors of radiation (PDR), includes all modern en-
gineering branches from space and paramilitary equipment to household
appliances, public and individual security and fire alarm systems [1—9].
The principle of operation of PDR is based on the temperature de-
pendence of polarization of sensitive element (SE) material and regis-
tration of electrical charge connected with polarization change in-
duced by temperature variation [2, 3, 5—9]. Radiation absorption by
the surface or volume of SE is the first and very important stage of ra-
diation conversion into the electrical response of thermal detectors [2,
3, 5]. That is why sensitive and frequency characteristics of commonly
used PDR with surface absorption are largely determined by thermo-
physical parameters of absorbing coating (AC) of SE [10—14].
Well-known technologies for making up the AC of PDR use thin dis-
perse layers of noble (Pt, Au and Ag) and other (Ni, Cr and Ni—Cr) met-
als evaporated in the conditions of ‘imperfect’ vacuum and deposited
in certain atmosphere and temperature conditions [10—13]. Thin layers
of different lacquer and paints [10, 14] formed by smearing or pulveri-
zation are also used as AC. These so-called metal and dielectric blacks
possess sufficient spectral characteristics in the near- and middle-IR
range [11, 14]. However, these blacks have relatively low thermal con-
ductivity and restrict the speed of response of PDR by the time of
thermal diffusion through the layer of AC [10, 12, 13] that demands
the further development of AC technologies.
CARBON NANOTUBES BASED BLACK ABSORBING COATINGS 139
Progress in modern technology allows enriching AC stock with
blacks based on carbon nanotubes (CNT), which are mainly character-
ized by the combination of high values of thermal and electrical con-
ductivity [15—17] and resulted in the development of effective absorb-
ing CNT-coating for pyroelectric detectors [17].
Recently, we reported about the development of AC based on thin
(∼ 1 μm) layers of SiO<Cu> metal—oxide composite [18] and AC based
on CNT-paint [19].
In a given paper, we present the results of the comparative study of
AC thin layers based on metal disperse layer and dielectric paint blacks
and also carbon nanotubes paint black as AC for sensitive elements of
pyroelectric detectors and other types of thermal detectors of radiation.
2. EXPERIMENTAL
2.1. Sample preparation
Metal-black AC were manufactured by evaporation of corresponding
metal (gold in this experiment) and deposition of its vapours on the SE
electrode surface under imperfect vacuum condition of 0.1—10 Torr in
nitrogen atmosphere with a low content of oxygen at the substrate
temperature of about 200 K [18].
For the manufacture of dielectric lacquer paint (DLP) black AC, the
solution of industrial multi-pigment black lacquer paint was used.
For the manufacture of CNT-based black AC, the carbon single wall
nanotubes (SWNT) prepared by the method of arc discharge in He-
atmosphere [20] were used. The characterization of these SWNT by
Raman scattering and electron microscopy was performed. The length
and diameter of the SWNT were of 1—2 μm and 14—15 Å, respectively.
Then, suspension on the base of SWNT crumbled preliminary, organic
binder and dissolvent were prepared.
The DLP-black AC and CNTP-black AC were prepared by depositing
a thin layer of solution of low viscosity on the SE electrode surface and
subsequent evaporating solvent at heightened temperature. After dry-
ing on the electrode surface were obtained the layers of 5—20 μm thick-
ness close to that of Au-black AC. For manufactured CNTP-black, AC
has the value of 20—50 kΩ/ surface resistance and a high degree of
blackness close to that of DLP-black and Au-black AC.
For the pyroelectric investigations, the SE with AC deposed directly
on the main surfaces of 100—200 μm LiNbO3 plates of polar Z-cut with
evaporated Cu/Cr-electrodes of 20—50 mm2
of area were formed. Such
SE with various types of AC were connected by means of a ring-shape
holder to the input of the FET matching stage [21] with variable from
high (∼ 10 GΩ at the frequency of 20 Hz) to relatively low (∼ 100 kΩ)
input impedance value.
140 S. L. BRAVINA, N. V. MOROZOVSKY, G. I. DOVBESHKO et al.
2.2. Measurements
For the optical investigations, Au-black, DLP-black and CNTP-black
AC were put on the electroded LiNbO3 thin plates. The measurements
of reflectance of the samples were performed in the middle infrared
range 2.5—25 μm with IFS 66 Bruker Instrument.
The pyroelectric response measurements were performed by the
modulation photopyroelectric thermowave method [22] in the fre-
quency range 10 Hz ≤ fm ≤ 100 kHz of modulation of IR-radiation flux.
The measuring system for thermowave probing allowed us to obtain the
amplitude-to-frequency ( )mU fπ and phase-to-frequency ( )mfπφ depend-
ences of pyroelectric response in two operation modes of pyroelectric
current and pyroelectric voltage characteristic for PDR operation. Due
to the fact that, in the pyroelectric current mode, 1 1/U U cπ π= ∝ γ ,
and, in the pyroelectric voltage mode, 2 1/ mU U c fπ π= ∝ γ ε , where γ is
the pyroelectric coefficient, с1 is the volume heat capacity, there is pos-
sibility to evaluate the dielectric permittivity ε from pyroelectric
measurements [2, 21, 22] by introducing the dielectric ratio
1 2/ mD U U fπ π π π= ∝ ε .
The connection of amplitude and phase of pyroelectric response with
the thermal parameters of both SE of PDR and AC material in conse-
quence of the fundamental frequency dependence of the length of tem-
perature wave
1/2( / )T T ma fλ = π , where aT is the thermal diffusivity
[18, 19, 22], allows one to estimate the value of aT for material of AC by
analysing ( )mU fπ and ( )mfπφ dependences.
3. RESULTS AND DISCUSSION
3.1. Optical IR Characterization
In Figure 1, the spectral dependences of reflectance R(ν) (Fig. 1, a) and
absorbance (Fig. 1, b) of Au-black, DLP-black and CNTP-black in IR-
spectrum range of wavenumbers 400 ≤ ν ≤ 4000 cm
−1
corresponding to
that of wavelengths 5 ≤ λ ≤25 μm are presented.
For Au-black, R(ν) value changes in the limits 1.5—6% and corre-
sponding A(λ) value changes in the limits 94—98%. For both types of
the paints, R(ν) change is no more than 3%. Due to opacity of prepared
paint layers, the A(λ) value is no less than 97%.
It should be pointed out the different shapes of obtained spectra for
Au-black, DLP-black and CNTP-black in all spectral range and particu-
larly in the range of 8—20 μm.
The regularity of R(ν) and A(λ) spectrum for CNTP-black is better
than for DLP-black, which results in a better level of spectral non-
selectivity and in a higher value of integral absorbance of CNTP-black
in the investigated spectral range. The absorbance value for CNTP-
CARBON NANOTUBES BASED BLACK ABSORBING COATINGS 141
black AC is higher and its spectral uniformity is better than the same
for DLP-black AC.
3.2. Photopyroelectric Characterization
In Figure 2, the dependences of 1,2 ( )mU fπ and 1,2 ( )mfπφ are shown for SE
of PDR obtained under irradiation of the Cu-electrode without AC and
the other one with AC from Au-black.
Significant difference in 1,2Uπ levels for the electrodes with AC and
without it at low frequencies corresponds to a good quality of Au-
black.
The existence of 180°-difference for 1,2 ( )mfπφ dependences obtained
for Cu-electrode side and Au-black side corresponds to different signs
of pyroelectric reaction at the different polar Z
+
and Z
−
surfaces.
Flat frequency dependences of 1Uπ , 2 mU fπ , Dπ and 1,2πφ under irra-
diation of the side of Cu-electrode (Fig. 2, left side) correspond to
thermal, polar and dielectric uniformity.
Then, the following types of 1( )mU fπ , 1( )mfπφ and 2( )mU fπ , 2 ( )mfπφ de-
pendences are characteristic [3, 5, 18, 19, 22]: 1( ) const( )m mU f fπ = and
1( ) const( )m mf fπφ = in the pyroelectric current mode, 2( ) 1 /m mU f fπ ∝ and
2( ) const( )m mf fπφ = in the pyroelectric voltage mode. In this case,
2 ( ) const( )m m mU f f fπ = and 1 2( ) ( ) / ( ) const( )m m m m mD f U f U f f fπ π π π= ∝ ε = ,
and also ϕπ2 − ϕπ1 = 90° due to capacitive character of current and voltage
in the circuit of pyroelectric SE.
The noticeable approaching the values of 1( )mU fπ to 2( )mU fπ and
1( )mfπφ to 2( )mfπφ under fm increasing is connected with deviation from
a b
Fig. 1. Spectral dependences of reflectance (a) and absorbance (b) of Au-
black, dielectric lacquer-paint black and CNT-paint black.
142 S. L. BRAVINA, N. V. MOROZOVSKY, G. I. DOVBESHKO et al.
the conditions of pyroelectric current mode. Under that with fm in-
creasing, the SE impedance 1 2 mf Cπ (C is the total capacity of SE and
load circuit) becomes less than the load resistance LR and the inequal-
ity 2 1m Lf R Cπ << necessary for performing pyroelectric current mode
changes for the opposite 2 1m Lf R Cπ >> , characteristic for the pyroelec-
tric voltage mode, which leads to the coincidence of the dependences.
The weak high-frequency drop of 2( )m mU f fπ , 1( )mU fπ and increase of
2( )mfπφ noticeable at the high-frequency interval corresponds to the
existence of under-electrode non-homogeneity. Taking into considera-
tion the value of aT = 1.5⋅10−6
m
2/s known for LiNbO3 [5], with regard
to the value of λT for fm = 40 kHz, it is possible to evaluate the thickness
of this non-homogeneity as about 3 μm.
Under irradiation from the side of Au-black (Fig. 2, right side), flat
frequency dependences of 1Uπ , 2 mU fπ and 1,2πφ are characteristic at low
frequencies which corresponds to inequality / 1T Lλ >> between the
length of temperature wave and the thickness L of the AC layer. At fre-
quencies higher than 1 kHz, we observed a significant decrease of re-
sponse amplitude and additional positive phase shift. Such peculiarities
are connected with damping action of AC, which is manifested under
approaching λT to L with increasing fm value. Under further increase of
fm, the inequality / 1T Lλ < is getting valid. Enhancement of this ine-
quality leads to decrease of exponential in respect to
1/2
mf multiplier for
fm
2
2
1
2
1
Fig. 2. Modulation frequency dependences, 2 ( )mU fπ , 2 ( )m mU f fπ and ( )mD fπ and
also 1( )mfπφ and 2( )mfπφ for SE of PDR with AC from Au-black on one side.
CARBON NANOTUBES BASED BLACK ABSORBING COATINGS 143
the response amplitude
1/2( ) exp( / ) exp( ( / ) )m T m TU f L L f aπΔ ∝ − λ = − π
and increase of a linear in respect to
1/2
mf contribution to the phase
1/2( ) / ( / )m T m Tf L L f aπΔφ = λ = π . As a result, with increasing fm, the
level of pyroelectric response under irradiation from the Au-black side
becomes even lower than under irradiation from the side of the Cu-
electrode (see Fig. 2, left and right sides).
In Figure 3, 1,2 ( )mU fπ , 2 ( )m mU f fπ , ( )mD fπ and 1,2( )mfπφ dependences for
SE of PDR with AC from DLP-black and AC from CNTP-black are
shown.
Under irradiation of the side with DLP-black AC (Fig. 3, a), the be-
haviour of 1,2 ( )mU fπ and 1,2 ( )mfπφ dependences similar to that observed
for Au-black AC (Fig. 2) is shifted to higher frequencies and the region
of high-frequency drop of amplitude—frequency dependence is ob-
served for fm > 5 kHz.
Under irradiation of the side with CNTP-black (Fig. 3, b), the de-
pendences of 1,2 ( )mU fπ as for DLP-black are less sharp than observed in
the case of irradiation as Au-black AC (see Fig. 2 and Fig. 3, b). Near
the same levels of 1,2Uπ for Au-black AC, DLP-black AC and CNTP-
black AC at low frequencies correspond to good absorption of CNTP-
black AC.
The high-frequency drop of 2( )m mU f fπ and increase of 2( )mfπφ for
CNTP-black AC connected with thermal damping are not so sharp and
are observed at the frequencies of 1 order higher than those ones for
AC from Au-black (compare Fig. 2 and Fig. 3, b).
a b
Fig. 3. Modulation frequency dependences 1( )mU fπ , 2 ( )mU fπ , 2( )m mU f fπ and
( )mD fπ and also 1( )mfπφ and 2( )mfπφ for similar SE of PDR with AC from
dielectric lacquer-paint black (a) and AC from CNT-paint black (b).
144 S. L. BRAVINA, N. V. MOROZOVSKY, G. I. DOVBESHKO et al.
The obtained 1,2( )mU fπ and 1,2( )mfπφ dependences for SE with differ-
ent AC allow one to estimate the value of thermal diffusivity of each
AC material. It can be done by analyzing the characteristic depend-
ences of ( )mU fπ and ( )mfπφ in the frequency range where the thermal
damping is significant. The estimated aT values for Au-black AC, DLP-
black AC and for CNTP-black AC are presented in Table.
The obtained Ta values for CNTP-paint black are at least of an order
of value higher than аT values for other black AC under investigation
and are comparative with aT values for massive graphite. It can be con-
nected with a high contribution of relatively large regions of high con-
tacted CNT-bundles interconnected through developed surrounding of
small CNT-bunches.
4. CONCLUSION
Combination of enhanced spectral characteristics and thermal parame-
ters of CNT paint black in comparison with those inherent to Au-black
and dielectric lacquer paint black with foresight of further progress in
CNT-based technologies allows us to consider the CNT-based paint
black as promising for absorbing coatings of thermal detectors of ra-
diation.
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Carbon Nanotube Paint Black 5—20 (5—25)⋅10−6
Graphite (extruded) 200—500 (2—7)⋅10−5
CARBON NANOTUBES BASED BLACK ABSORBING COATINGS 145
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