Investigations of SP-AMS Carbon Ion Distributions as a Function of Refractory Black Carbon Particle Type

Figures & data

TABLE 1 Refractory black carbon (rBC) materials sampled in this work

#	Particle Type	Carbon type (CAS) and usage	Source of particles (lot #)	Generation technique
1.	Aquadag	Graphite (7782-42-5). Used for coatings for light absorption and electrostatics.	Acheson Colloids Company, Port Huron, MI (Product 5307562, lot 8867)	Atomized
2.	Biomass burning	Open air biomass burning emissions.	FLAME3 study (McMeeking et al. 2009)	Open air flame
3.	Carbon nanoparticles	Amorphous carbon (7440-44-0), made by laser decomposition, average particle size 30 nm.	Sigma-Aldrich Inc. (Produce 633100)	Atomized
4.	Diesel exhaust	On road diesel truck exhaust.	Caldecott Tunnel (Dallmann et al. 2014)	Internal diesel engine
5.	Ethylene pre-mixed flame soot	Fuel equilivance ratios from 2–5.	Premixed flat burner flame source.	Flame (Cross et al. 2010)
6.	C60	Buckminsterfullerene, Buckyballs, Carbon-60 (99685-96-8), sublimed.	Materials and Elecrochemical Research (MER) Corporation	Dry powder aerosolization (Tiwari et al. 2013)
7.	Alfa Aesar fullerene soot	Fullerene-enriched soot generated by Kräetschmer-Huffman arc process (Kräetschmer et al. 1990).	Alfra Aesar (Product 40971, lots F12S011 and L20W054)	Atomized
8.	Nano-C fullerene black	Fullerene-enriched carbon black generated by Nano-C's proprietary II-G low-pressure, combustion-based technology.	Nano-C, Westwood, MA (lot DR-070224)	Atomized
9.	Glassy carbon spheres	Amorphous carbon (7440-44-0).	Yokai Carbon Co. and Alfa Aesar (Product 398004, type 1, lot A06Q23)	Atomized
10.	Methane diffusion flame soot	Net equivalence ratios from 0.6–0.9.	Diffusion flame source	Flame (Stipe et al. 2005)
11.	Norit SX-activated charcoal	Acid washed, steam activated carbon with high S/V ratio and adsorptive capacity.	Norit	Atomized
12.	Regal black	Carbon black or furnace black (1333-86-4). Used as an additive for plastic and rubber, pigment, chemical reagent, batteries, and refractories.	Cabot Corporation, Billerica, MA (Product 400R, lot GP-3901)	Atomized

FIG. 1. Normalized positive ion mass spectra for (a) Regal black, (b) ethylene soot, (c) Nano-C fullerene black, and (d) C₆₀. Mass spectra represent the measured refractory carbon ion count rate (Hz) normalized to the total carbon ion signal as a function of mass-to-charge ratio (m/z) up to 2000 m/z. The displayed m/z scale corresponds to carbon cluster ions from C₁⁺ (12 m/z) to C₁₆₆⁺ (1992 m/z) as shown on top axis. The C₁⁺–C₅⁺ region has been expanded for clarity. The top of the figure shows the SP-AMS mass spectrometric categories and the related structures for stable carbon clusters.

FIG. 2. Positive carbon ion mass spectra measured in (a) exhaust emissions from a single on-road diesel truck, and (b) smoke from the biomass burning of lodgepole pine. The C₁⁺–C₅⁺ region (1–60 m/z) has been expanded for clarity, and the intensity scales for the C₆⁺ to C₈₃⁺ region (60–1000 m/z) have been expanded to 1:10 (right axes).

FIG. 3. (a) Normalized carbon ion mass spectra for Nano-C fullerene black with electron beam on (black) and off (gray/red). (b) Normalized mass spectra for Alfa Aesar fullerene soot with electron beam on (black) and off (gray/red). The laser vaporizer is on in both cases. (c) The ratio of carbon ions with electron beam OFF-to-ON for both materials as a function of m/z. The fractional carbon ion signals for electron beam OFF-to-ON from pure C₆₀ is also included in (c) for the five m/z ion peaks with reasonable signal-to-noise; C₆₀⁺ is the lowest point at the highest m/z in this case.

FIG. 4. Laser power studies for (a) Regal black, showing the invariance of C₁⁺–C₅⁺ with laser power, (b) Nano-C fullerene black, showing different laser power dependences for C₃⁺, C₆₀²⁺, C₆₀⁺, and the total fullerene ion signal (C₃₀⁺/C₆₀²⁺ to C₁₆₆⁺), and (c) C₆₀, showing similarities in laser power dependences for the parent C₆₀⁺ and C₆₀²⁺ ions and the fragment C₃⁺ and C₅₈⁺ ions. The laser power axis is a relative measure of the intracavity laser vaporizer power obtained by measuring light leaking through the mirror end of the laser cavity (see text for details).

FIG. 5. Normalized negative carbon ion mass spectra for (a) Regal black, (b) Nano-C fullerene black, and (c) C₆₀. The scales for the right axes of (a) and (b) are 1:70; the scale for the left axis of (c) is 1:200. The C₁⁻–C₁₀⁻ region has been expanded for clarity.

McMeeking, G. R., Kreidenweis, S. M., Baker, S., Carrico, C. M., Chow, J. C., Collett, J. L., Hao, W. M., Holden, A. S., Kirchstetter, T. W., Malm, W. C., Moosmüller, H., Sullivan, A. P., and Wold, C. E. (2009). Emissions of Trace Gases and Aerosols During the Open Combustion of Biomass in the Laboratory. J. Geophys. Res., 114:D19210.

 Web of Science ®Google Scholar

Cross, E. S., Onasch, T. B., Ahern, A., Wrobel, W., Slowik, J. G., Olfert, J., Lack, D. A., Massoli, P., Cappa, C. D., Schwarz, J. P., Spackman, J. R., Fahey, D. W., Sedlacek, A., Trimborn, A., Jayne, J. T., Freedman, A., Williams, L. R., Ng, N. L., Mazzoleni, C., Dubey, M., Brem, B., Kok, G., Subramanian, R., Freitag, S., Clarke, A., Thornhill, D., Marr, L. C., Kolb, C. E., Worsnop, D. R., and Davidovits, P. (2010). Soot Particle Studies – Instrument Inter-Comparison – Project Overview. Aerosol Sci. Technol., 44:592–611.

 Web of Science ®Google Scholar

Tiwari, A. J., Fields, C. G., and Marr, L. C. (2013). A Cost-Effective Method of Aerosolizing Dry Powdered Nanoparticles. Aerosol Sci. Technol., 47:1267–1275.

 Web of Science ®Google Scholar

Krätschmer, W., Fostiropoulos, K., and Huffman, D. R. (1990). The Infrared and Ultraviolet Absorption Spectra of Laboratory-Produced Carbon Dust: Evidence for the Presence of the C60 Molecule. Chem. Phys. Lett., 170:167–170.

 Web of Science ®Google Scholar

Stipe, C. B., Higgins, B. S., Lucas, D., Koshland, C. P., and Sawyer, R. F. (2005). Inverted Co-Flow Diffusion Flame for Producing Soot. Rev. Sci. Instrum., 76:023908.

 Web of Science ®Google Scholar