Roeland Dijkema, MScBrussels, 3rd of April 2019

Sub 20 nm generation of soot particles using the VSP-G1 nanoparticle generator

CONFIDENTIAL

AgendaTopic

Company1

Introduction2

Technology3

Particle deposition4

Results5

Summary6

Philosophy

We make machines that produce nanostructured materials. Our philosophy is that these machines should be simple to operate and based on a scalable principle.

VSPARTICLE

Accessories G-1 NMP-1G-1

~ 40 cm

Introduction

VSPARTICLE timeline Introduction

2014

Start of VSPARTICLE,

development of the G1

2017

3 Launching

customers

Full management

team covering all

angles of business

2018

International expansion to

research oriented

markets in the Americas,

Europe and Asia

1988

Invention of spark

ablation by Andreas

Schmidt-Ott

#REENGINEERResearch 1-300 Hz ~ milligramsIndustry 10.000-25.000 Hz ~ 100s milligrams

TechnologySpark ablation

Technology

• Ablation/evaporation andcondensation

• Electric discharge

≈ 104 K, ≈10-5 s

• Rapid quench

≈ 107 K s-1

• ‘Mild’ conditions

• Versatility• Metals

• Carbon

• Oxides

• Alloys[Schwyn 1988, J. Aerosol Sci., 19 (5), p.639.]

How particle growth works in the system

The process takes place under atmospheric conditions

Particle Production inside G1

Technology

TechnologyParticle formation in sparks

[Feng et al. 2016, J. Phys. Chem. C., 120 (1), p. 621.][Tabrizi et al. 2009, J. Nanopart. Res., 11 (2), p. 315]

• Smoluchowski:d 𝑁

d 𝑡= −

1

2𝛽𝑁2

𝑑𝑝 ∝ 𝑁−1

3

• Controlled through voltage, current and flow

𝑁0 ∝ሶ𝑚

𝑄∝

𝑈 𝐼

𝑄

𝑡 =𝑉

𝑄

𝑑𝑝 ∝𝑉 ሶ𝑚

𝑄2

13

Possibilities with G1Materials

Technology

CONFIDENTIAL

VSP-G1 designFlexible flow configurations

ResultsVSP-G1 designFlexible flow configurations

VSP-G1 designAu, Ar, Crossflow

Results

0

1

2

3

4

1 10 100

dN

+ /d

log

dp

[cm

-3]

×10

7

Particle size [nm]

Throughflowcrossflowhollow inlethollow outlet

Ag, 1.7kV, 4 mA, 4 slm

- Tuneable size distribution

- Crossflow highestconcentration

- Throughflow smallest meandiameter

Material: Copper

Carrier Gas: Argon

Flowrate: 1 L/min

Voltage: 1.0 kV

Current: 5.0 mA

Stability of 5 nm particles

StDev: <2%

Measured with DMA (DifferentialMobility Analyzer) + Electrometer & FD/C

Size-selected stabilityOutput VSP-G1 example

Results

Size-selected stability measurementStability measurement

Results

µ, σ

Warm up Measurement

0

0.5

1

1.5

2

2.5

3

0E+0

1E+5

2E+5

3E+5

4E+5

5E+5

6E+5

0 500 1000 1500

Gap

Vol

tage

[kV]

Part

icle

cou

nt [c

m-3

]

Time [s]

Particle Count Voltage setpoint Gap Voltage

σ=3.4%

σ=1.5%

σ=1.7%σ=1.3%

VSP-G1 emission experimentsCarbon output

Results

0,00E+00

1,00E+05

2,00E+05

3,00E+05

4,00E+05

5,00E+05

6,00E+05

7,00E+05

8,00E+05

9,00E+05

0,01 0,02 0,03 0,04 0,05 0,06 0,07 0,08 0,09 0,1

CO

NC

EN

TR

AT

ION

(#

/CM

3)

PARTICLE SIZE (UM)

1.3 kV, 8 mA, 20 SLM 1.3 kV, 8 mA, 15 SLM 1.3 kV, 8 mA, 10 SLM 1.3 kV, 8 mA, 5 SLM 1.3 kV, 8 mA, 2 SLM

Carbon output

ResultsVSP-G1 emission experiments

CONFIDENTIAL

Who is already using itSome of our customers

• R&D scale generator

• Commercially available

• Outputs an aerosol of nanoparticles

• Specifications:

• Particle size between few atoms to 300 nm

• Particle generation rate approx. 1 ~ 10 mg/h

• Particle concentration 108 ~ 1011 cm-3

VSP-G1 Nanoparticle Generator

Thank you!

The VSPARTICLE team

Carbon output(Dekati Elpi+)

Spark ablation Setup Technology

- Self-charging in plasma

- Electrostatic precipitation

- Electrostatic force towards HV Electrode

- Small particles overpresented

Self-chargingNo neutralizer in setup

Results

Tabrizi et al. 2015

Flow configurationInfluence on Size distribution

Results

0

1

2

3

4

1 10 100

dN

+ /d

log

dp

[cm

-3]

×10

7

Particle size [nm]

Throughflowcrossflowhollow inlethollow outlet

Ag, 1.7kV, 4 mA, 4 slm

- Tuneable size distribution

- Crossflow highest

concentration

- Throughflow smallest mean

diameter

FlowrateInfluence on size distribution

Results

- At highest flowrate only

primary particles

- Dilution at higher flowrate

- Current, Voltage Influence

0

2000

4000

6000

8000

10000

12000

14000

16000

18000

20000

1 10

Raw

Counts

(#/c

c)

Dp (nm)

Size distributions (Throughflow, Au, 1kV, 5mA)

1.5 SLPM

3.3 SLPM

6.6 SLPM

10 SLPM

15 SLPM