Chamber and feedthroughs
- Chamber: 24” x 24” x 24” stainless steel
- View port #1: 6” x 4” rectangular
- View port #2: circular 4.5” diameter
- Electric feedthroughs: three on left wall
- Optical fiber feedthroughs: four on the ceiling
- Feedthroughs for valves and pressure meter: three on right wall
- Feedthroughs for coolant: two on right wall
Vacuum system
- Scroll pump (Edwards XDS35i): ultimate vacuum (total pressure): 0.008 Torr
- Pressure meter: convection-enhanced Pirani gauge (Kurt J. Lesker Company® model KJL300808)
- Vacuum reached: ~1x10-2 mbar when maintaining the continuous pumping
Input system for gas mixture
- Ball and needle valves
- CO2 (or desired gaseous mixture) in the pressure range 1×10-2 mbar to ambient pressure
Sample temperature
- Coolant: LN2
- Delivery of coolant: evaporation of LN2 from a dewar via the heating of an immersed electric resistor
- T control: RTD and CN7600 autotune controller (OMEGA Engineering Inc.)
- Cold plate: a toroid-shape double-wall copper block
- Sample cups: 24 cups of 0.5” internal diameter × 0.4” internal depth made of cooper in good thermal contact with cold plate
- T range: RT to -100°C
- Sample T homogeneity: ±0.5 °C at 0°C or ±5 °C at - 40 °C
Chamber T & RH monitoring
- T & RH data logger (Extech Instruments RHT20)
Imager and Spectral Sensors
Raman equipment
- Laser: 532nm CW laser beam, ~ 10 mW at sample
- Raman probe: 5 mm WD, ~ 20 µm Ø laser beam, 200 μm core Ø collecting optical fiber
- Raman spectrograph: 100 - 4300 cm-1, 4-5 cm-1 spectral resolution
LIBS equipment
- Laser: 1064 nm with 7ns pulse width, 1-15 Hz, free-space laser delivery through view port #2
- Collecting optical fiber: 230 µm Ø UV enhanced optical fiber cable (Ocean Optics)
- LIBS spectrograph: Echelle grating spectrograph with ICCD as detector (Andor Company)
Imager
- GigE™ video camera with1.05um/pixel and 1200 μm × 1100 μm field of view
- Co-axis with LIBS laser optical path
Sample preparations
- Solid sample: place in sample cups
- Liquid sample: to be placed in sample cups