Our group conducts both applied and fundamental research to accelerate the production and application of next-generation, low-carbon fuels. One particular area of focus is hydrogen energy. Ongoing research efforts involve developing advanced sensor for hydrogen technologies including solar-thermal methane pyrolysis for hydrogen production and hydrogen blending in natural gas pipelines for decarbonized power generation. 

Relevant publications:

1. C. Wei*, A. Klingberg, C. L. Strand, and R. K. Hanson, ‘Measurement of hydrogen and nitrogen via collision-induced infrared absorption’, International Journal of Hydrogen Energy, vol. 93, pp. 364–373, 2024.

2. C. Wei*, M. Abuseada, B. Jeevaretanam, T. S. Fisher, and R. M. Spearrin, ‘Concentrated solar-thermal methane pyrolysis in a porous substrate: Yield analysis via infrared laser absorption’, Proceedings of the Combustion Institute, vol. 39, no. 4, pp. 5581–5589, 2023.

3. B. Jeevaretanam*, M. Abuseada, C. Wei, N. Q. Minesi, T. S. Fisher, and R. M. Spearrin, ‘Transient analysis of solar pyrolysis and hydrogen yield via interband cascade laser absorption spectroscopy of methane, acetylene, ethylene, and ethane’, Applications in Energy and Combustion Science, vol. 16, p. 100223, 2023.

4. M. Abuseada*, C. Wei, R. M. Spearrin, and T. S. Fisher, ‘Solar--thermal production of graphitic carbon and hydrogen via methane decomposition’, Energy & Fuels, vol. 36, no. 7, pp. 3920–3928, 2022.

Our group has pioneered the novel multi-dimensional, quantitative laser absorption imaging (LAI) technique for species and temperature measurements in high-temperature reacting flows. By integrating state-of-the-art infrared laser absorption spectroscopy with advanced inversion methods, including regularization and deep neural networks, we achieve unprecedented spatio-temporal resolution for quantitative thermochemical properties. This innovative approach enables detailed insights into the complex coupling of chemical kinetics and transport processes in flames, advancing the development of accurate computational flame models.

Relevant publications:

1. C. Wei* and R. M. Spearrin, ‘Four-dimensional laser absorption cinematography of species and temperature dynamics at 2 kHz in reacting flows’, Optics Letters, vol. 49, no. 1, pp. 141–144, 2023.

2. C. Wei, K. K. Schwarm, D. I. Pineda, and R. M. Spearrin, ‘Volumetric laser absorption imaging of temperature, CO and CO2 in laminar flames using 3D masked Tikhonov regularization’, Combustion and Flame, vol. 224, pp. 239–247, 2021.

3. C. Wei*, K. K. Schwarm, D. I. Pineda, and R. M. Spearrin, ‘Deep neural network inversion for 3D laser absorption imaging of methane in reacting flows’, Optics letters, vol. 45, no. 8, pp. 2447–2450, 2020.

4. C. Wei*, D. I. Pineda, C. S. Goldenstein, and R. M. Spearrin, ‘Tomographic laser absorption imaging of combustion species and temperature in the mid-wave infrared’, Optics express, vol. 26, no. 16, pp. 20944–20951, 2018. 

5. C. Wei*, D. I. Pineda, L. Paxton, F. N. Egolfopoulos, and R. M. Spearrin, ‘Mid-infrared laser absorption tomography for quantitative 2D thermochemistry measurements in premixed jet flames’, Applied Physics B, vol. 124, no. 6, p. 123, 2018.

It is expected that future ultra-low emission engine concepts, regardless of fuel, will require improved understanding of combustion chemistry and device performance at elevated pressures. Our group conducts fundamental research in modeling complex high-pressure spectroscopic phenomena including line-mixing effects and collision-induced absorption to help develop quantitative diagnostics for supercritical reacting flows relevant to next-generation energy devices.

Relevant publications:

1. C. Wei*, A. Klingberg, C. L. Strand, and R. K. Hanson, ‘Measurement of hydrogen and nitrogen via collision-induced infrared absorption’, International Journal of Hydrogen Energy, vol. 93, pp. 364–373, 2024.

2. C. Wei*, K. K. Schwarm, D. I. Pineda, and R. M. Spearrin, ‘Quantitative volumetric laser absorption imaging of methane and temperature in flames utilizing line-mixing effects’, Proceedings of the Combustion Institute, vol. 39, no. 1, pp. 1229–1237, 2023.

3. F. A. Bendana*, D. D. Lee, C. Wei, D. I. Pineda, and R. M. Spearrin, ‘Line mixing and broadening in the v (1→ 3) first overtone bandhead of carbon monoxide at high temperatures and high pressures’, Journal of Quantitative Spectroscopy and Radiative Transfer, vol. 239, p. 106636, 2019. 

4. J. Terragni* et al., ‘Collision induced absorption in HITRAN2024: Enhanced and improved data for atmospheric and planetary studies’, Journal of Quantitative Spectroscopy and Radiative Transfer, p. 109631, 2025.