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Improving airborne nanoparticle and cluster detection with the
butanol based laminar flow condensation nuclei counters
Grimm 5.403 and 5.412. Gerhard Steiner1,2,3, M. Orzan1, I. Nagler1, E. Petrakakis1, M. Selimovic1, C. Tauber1, F. Tettich3
1. University of ViennaAerosolphysics and Environmental Physics
Boltzmanngasse 5, 1090 Wien, Austria
2. University of InnsbruckInstitute of Ion Physics and Applied Physics
Technikerstrasse 25, 6020 Innsbruck, Austria
3. GRIMM Aerosol Technik GmbH & Co. KG AinringDorfstraße 9, 83404 Ainring, Germany
sub 3 nm nanoclusters, where to find them?
nucleation
particle formation condensational growth
-
+
molecular clustersprimary ions or
neutral molecules
~ 0.5 nm 1-2 nm 50-100 nm
larger particles
e.g. cloud condensation nuclei
trace gases; VOCs particles
scavenging by
pre-existing aerosol (loss)
“major fraction of particles
emitted by road
transportation are in size
range of 1.3 – 3.0nm”
“in semiurban roadside environment:
20-54% of total particle concentration
in ambient air”
traffic related aerosols
Rönkkö et al., 2017, PNAS
Nosko et al., 2017, AST
emissions from vehicle brakes:
„a significant number of 1.3 – 4.4 nm airborne particles”
„these particles should not be neglected in environmental and tribological studies.”
where else to find sub 3nm particles ?
detection of sub 3 nm particles?1) Aerosol Electrometers
• already possible since end of 19th century
(as reviewed e.g. by Flagan, 1998, Aerosol Sci. Technol, 28: 4, 301 — 380)
• need to be charged
• virtually no size dependent detection efficiency
• detection limit rather high
• 1 fA @ 2 L/min => 187 particles /cm³
• 0.3 fA @ 2 L/min => 56 particles/cm³
2) Condensation Particle Counters
• single particle detection possible
• detection of neutrals possible
• size dependent detection efficiency
• detection efficiency dependent on working fluid � chemical composition of particles
overview of nano-CPCs
adiabatic expansion CPCs
Pinterich et al. (2016) The versatile analyzing nuclei counter (vSANC). Aerosol Sci. Technol. 50: 947-958
mixing – type CPCs
Sgro & Fernández de la Mora (2004) A Simple Turbulent Mixing CNC for Charged Particle Detection Down to 1.2 nm,
Aerosol Sci. Technol., 38:1, 1 – 11
Vanhanen et al. (2011) Particle Size Magnifier for Nano-CN Detection, Aerosol Sci. Technol., 45:4, 533-542
thermally diffusive laminar flow CPCs
Stolzenburg and McMurry (1991) An Ultrafine Aerosol Condensation Nucleus Counter.
Aerosol Sci. Technol., 14: 1, 48 — 65
Hering et al. (2005) A Laminar-Flow, Water-BasedCondensation Particle Counter (WCPC).
Aerosol Sci. Technol., 39:7,659 – 672
Iida et al. (2009) Effect of Working Fluid on Sub-2 nm Particle Detection with a Laminar Flow Ultrafine Condensation
Particle Counter. Aerosol Sci. Technol., 43:1, 81-96
Hering et al. (2017) Detection near 1-nm with a laminar-flow, water-based condensation particle counter. Aerosol Sci.
Technol., 51:3, 354 - 362
what if none of those super sophisticated
instruments is available?
tune your “standard” lab CPC
https://tonyforever.deviantart.com https://ru.pngtree.com/freepng/superman_1647191.html
GRIMM 5412 GRIMM 5403
0 2 4 6 8 10 120
0.2
0.4
0.6
0.8
1
mobility diameter, D (nm)
CP
C c
ou
ntin
g e
ffic
ien
cy , e
ta (
-)
WOx
Ag
NaCl
0 2 4 6 8 10 120
0.2
0.4
0.6
0.8
1
mobility diameter, D (nm)C
PC
co
un
tin
g e
ffic
ien
cy , e
ta (
-)
WOx
Ag
NaCl
GRIMM 5412 GRIMM 5403
D50 = 4.0nmD50 = 5.0nmD50 = 5.4nm
D50 = 4.0nmD50 = 6.2nmD50 = 7.3nm
10°C
35°C1.2 L/min
10°C
36°C
GRIMM 5412 GRIMM 5403
GRIMM 5412 GRIMM 540336 - 10 35 - 10
40 - 7 40 - 7
GRIMM 5412 GRIMM 5403
Anne Maißer & Christian Tauber, University of Vienna:
onset saturation ratio for THA+ (1.43nm) : S = 4.138
standard 36 - 10tuned 40 - 7
standard 35 - 10tuned 40 - 7
GRIMM 5403
Qsh = 400-700 L/min
R = 15 @ 1 cm²/Vs (~1.4 nm)
Steiner et al., 2010, Aerosol Sci. Technol. 44: 4, 308 - 315,
UDMA 1 & 2
UDMA 4
Qsh = 700-1200 L/min
R = 30 @ 1 cm²/Vs (~1.4 nm)
• running in closed-loop
• channel length & width = 6.50 mm
• Qa = 6 - 20 L/min
Vienna type UDMA
counting efficiency measurements 1
UDMA 4 (2016)
Fernández de la Mora & Barrios-Collado (2017)
A bipolar electrospray source of singly charged salt clusters of
precisely controlled composition. Aerosol Sci. Technol . 51:6,
778-786
SEADM bipolar electrospray source
counting efficiency measurements 1
counting efficiency measurements 1
GRIMM 5403
UDMA 4
VIE- FCE
bipolar
electrospray
1.5 L/min
1.5 L/min
15 L/min
excess flow
zero air
≈ 900 L/min
THABr +20180118.021.dat
n=1
n=2
3
4
5
6
7 8 9
~ 2.6nm
0 1 2 3 4 5 6 7 8 9
0.5
1
1.5
2
2.5
3
3.5
4
4.5
50 1.42 2.00 2.46 2.84 3.17 3.47 3.75 4.01 4.25
SEADM bipolar electrospray source
inv. electrical mobility, 1/Z [Vs/cm²]
ion
concentr
ation
x 1
04
(cm
-3)
cluster diameter, D [nm]
THABr -20180118.023.dat
n=1
2
3
45
67 8 9
1011
12
13
~ 2.6nm
0 1 2 3 4 5 6 7 8 9
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
inv. electrical mobility, 1/Z [Vs/cm²]
ion
concentr
ation
x 1
04
(cm
-3)
0 1.42 2.00 2.46 2.84 3.17 3.47 3.75 4.01 4.25
cluster diameter, D [nm]
SEADM bipolar electrospray source
tuned GRIMM 5403 results
0 0.5 1 1.5 2 2.5 3 3.5 40
0.2
0.4
0.6
0.8
1
mobility diameter, D (nm)
CP
C c
ou
ntin
g e
ffic
ien
cy , e
ta (
-)
WOx + (standard settings)
THABr + (tuned)
TBAI + (tuned)
D50 = 4.0nm
D50 = 2.6nm
counting efficiency measurements 2
GRIMM 5403
NDMA
TSI 3068B
tube
furnace
1.5 L/min
1.5 L/min
3 L/min
zero air
24 L/min
241Am
0 0.5 1 1.5 2 2.5 3 3.5 40
0.2
0.4
0.6
0.8
1
mobility diameter, D (nm)
CP
C c
ou
ntin
g e
ffic
ien
cy , e
ta (
-)
WOx + (standard settings)
THABr + (tuned)
TBAI + (tuned)
Ag + (tuned)
Ag - (tuned)
NaCl + (tuned)
NaCl - (tuned)
D50 = 4.0nm
D50 = 2.6nm
D50 = 2.1nm
tuned GRIMM 5403 results
D50 = 1.9nm
D50 = 1.6nm
conclusions
• sub 3 nm (neutral) particle detection
• only few commercial instruments
• tuning of GRIMM 5403 CPC
• bipolar electrospray + high res. DMA
• tube furnace + nano DMA
0 0.5 1 1.5 2 2.5 3 3.5 40
0.2
0.4
0.6
0.8
1
mobility diameter, D (nm)
CP
C c
ou
ntin
g e
ffic
ien
cy , e
ta (
-)
WOx + (standard settings)
THABr + (tuned)
TBAI + (tuned)
Ag + (tuned)
Ag - (tuned)
NaCl + (tuned)
NaCl - (tuned)
D50 = 4.0nm
D50 = 2.6nm
D50 = 2.1nm
D50 = 1.9nm
D50 = 1.6nm
Acknowledgments University of Vienna Aerosol Group
Funding
Austrian Science Fund, FWF
project P27295-N20 „Chemical Composition of Atmospheric Clusters”
University of Innsbruck promotion grant for young researchers
project „Cluster Calibration Unit, CCU“
Science Fund of the federal state Tirol, Tiroler
Wissenschaftsfonds, project „nanoTOF – ICE“
S. Brilke, P. Wlasits and C. Tauber
