Alexander Nelson

All Publications

• Oxidant-assisted methane pyrolysis. Chemical science Gigantino, M., Moise, H., Haribal, V., Tong, A., Shen, J. P., Saad, D., Fishman, J., Nelson, A., Voorhis, H., Sun, E., Brandt, A., Gupta, R., Majumdar, A., Cargnello, M. 2025

  Abstract

  Methane pyrolysis has been proposed as a cost-competitive route to produce low-CO2-emissions hydrogen that can utilize today's infrastructure to supply feedstock and manage waste, and thereby be rapidly scalable. However, this process faces challenges such as catalyst deactivation and carbon build-up that hinder its large-scale implementation. Pyrolysis is usually conducted in the absence of oxidizers to avoid combustion products such as CO2. Here, we demonstrate that the addition of small concentrations of an oxidant to a methane pyrolysis reaction on Fe-based catalysts prevented catalyst deactivation and increased the net production of carbon and hydrogen. Methane pyrolysis in the presence of a small amount of CO2 demonstrated a twofold increase in carbon yield and a 7.5-fold increase in hydrogen concentration in the effluent compared to that of a pure methane feed during 1 h operation in a fluidized bed reactor at 750 °C. A similar beneficial effect was observed by adding small amounts of H2O in the feed. We provide evidence that the cyclic formation and decomposition of an iron carbide catalyst phase allowed for increased methane decomposition and significant carbon removal from the catalyst surface, thus increasing carbon and hydrogen yields. A similar result was obtained for Ni- and Co-based catalysts.

  View details for DOI 10.1039/d5sc00768b

  View details for PubMedID 40556728

  View details for PubMedCentralID PMC12183648

• A semi-continuous process for co-production of CO2-free hydrogen and carbon nanotubes via methane pyrolysis CELL REPORTS PHYSICAL SCIENCE Sun, E., Zhai, S., Kim, D., Gigantino, M., Haribal, V., Dewey, O. S., Williams, S. M., Wan, G., Nelson, A., Marin-Quiros, S., Martis, J., Zhou, C., Oh, J., Randall, R., Kessler, M., Kong, D., Rojas, J., Tong, A., Xu, X., Huff, C., Pasquali, M., Gupta, R., Cargnello, M., Majumdar, A. 2023; 4 (4)

  View details for DOI 10.1016/j.xcrp.2023.101338

  View details for Web of Science ID 001000123600001

• Reply to the 'Comment on "Low-cost solutions to global warming, air pollution, and energy security for 145 countries"' ENERGY & ENVIRONMENTAL SCIENCE Jacobson, M. Z., von Krauland, A., Coughlin, S. J., Dukas, E., Nelson, A. H., Palmer, F. C., Rasmussen, K. R. 2023

  View details for DOI 10.1039/d2ee03964h

  View details for Web of Science ID 000932420700001

• Low-cost solutions to global warming, air pollution, and energy insecurity for 145 countries ENERGY & ENVIRONMENTAL SCIENCE Jacobson, M. Z., von Krauland, A., Coughlin, S. J., Dukas, E., Nelson, A. H., Palmer, F. C., Rasmussen, K. R. 2022

  View details for DOI 10.1039/d2ee00722c

  View details for Web of Science ID 000817565500001

• Transitioning All Energy in 74 Metropolitan Areas, Including 30 Megacities, to 100% Clean and Renewable Wind, Water, and Sunlight (WWS) ENERGIES Jacobson, M. Z., von Krauland, A., Burton, Z. M., Coughlin, S. J., Jaeggli, C., Nelli, D., Nelson, A. H., Shu, Y., Smith, M., Tan, C., Wood, C. D., Wood, K. D. 2020; 13 (18)

  View details for DOI 10.3390/en13184934

  View details for Web of Science ID 000580912100001