Kesha Tamakuwala

All Publications

• Porous materials: The next frontier in energy technologies SCIENCE Farber, E. M., Seraphim, N. M., Tamakuwala, K., Stein, A., Rucker, M., Eisenberg, D. 2025; 390 (6772): eadn9391

  Abstract

  Porous materials with pore sizes spanning the range from molecular to macroscopic dimensions (from angstroms to centimeters) are essential in electrochemical, thermoelectric, nuclear, and solar power sources and in the extraction of oil, gas, and geothermal heat. To enable the clean, fast, and efficient conversion of energy, the porous structure must be designed to allow, modulate, or block the flow of energy transfer vectors. The most important energy streams are mass, charge, heat, radiation, and pressure, and they must be optimized while packing the optimal surface area per device volume. In this Review, we analyze the physical processes that enable energy transfer in porous structures, highlighting recent advances in the design, characterization, modeling, and fundamental understanding of porosity that have enabled breakthroughs across the landscape of energy technologies.

  View details for DOI 10.1126/science.adn9391

  View details for Web of Science ID 001611711400011

  View details for PubMedID 41166459

• Intermediate-Temperature Reverse Water-Gas Shift under Process-Relevant Conditions Catalyzed by Dispersed Alkali Carbonates. JACS Au Tamakuwala, K. N., Kennedy, R. P., Li, C. S., Mutz, B., Boller, P., Bare, S. R., Kanan, M. W. 2025; 5 (3): 1083-1089

  Abstract

  Current reverse water-gas shift (RWGS) technologies require extreme temperatures of >900 °C. The ability to perform RWGS at lower temperatures could open new opportunities for sustainable chemical and fuel production, but most catalyst materials produce methane and coke at lower temperatures, especially at elevated pressures targeted for industrial processes. Here we show that transition-metal-free catalysts composed of K2CO3 or Na2CO3 dispersed on commercial γ-Al2O3 supports (K2CO3/γ-Al2O3 and Na2CO3/γ-Al2O3) are highly effective RWGS catalysts in the intermediate-temperature regime. At a high gas hourly space velocity of 30,000 h-1 and operating pressure of 10 bar, K2CO3/γ-Al2O3 reached RWGS equilibrium-limited CO2 conversion at 550 °C and was 100% selective for CO at all temperatures tested (up to 700 °C). Na2CO3/γ-Al2O3 was also 100% CO-selective and only slightly less active. Both catalysts were stable for hundreds of hours on stream at 525 °C and tolerated large quantities of methane and propane impurity in the CO2/H2 feed. The unique performance attributes, combined with the low-cost components and extremely simple synthesis, make dispersed carbonate RWGS catalysts attractive options for industrial application.

  View details for DOI 10.1021/jacsau.5c00127

  View details for PubMedID 40151267

  View details for PubMedCentralID PMC11937989

• Electrified thermochemical reaction systems with high-frequency metamaterial reactors JOULE Lin, C. H., Wan, C., Ru, Z., Cremers, C., Mohapatra, P., Mantle, D. L., Tamakuwala, K., Hofelmann, A. B., Kanan, M. W., Rivas-Davila, J., Fan, J. A. 2024; 8 (10)

  View details for DOI 10.1016/j.joule.2024.07.017

  View details for Web of Science ID 001338938500001

• Understanding hydrazine oxidation electrocatalysis on undoped carbon PHYSICAL CHEMISTRY CHEMICAL PHYSICS Burshtein, T. Y., Tamakuwala, K., Sananis, M., Grinberg, I., Samala, N., Eisenberg, D. 2022

  Abstract

  Carbons are ubiquitous electrocatalytic supports for various energy-related transformations, especially in fuel cells. Doped carbons such as Fe-N-C materials are particularly active towards the oxidation of hydrazine, an alternative fuel and hydrogen carrier. However, there is little discussion of the electrocatalytic role of the most abundant component - the carbon matrix - towards the hydrazine oxidation reaction (HzOR). We present a systematic investigation of undoped graphitic carbons towards the HzOR in alkaline electrolyte. Using highly oriented pyrolytic graphite electrodes, as well as graphite powders enriched in either basal planes or edge defects, we demonstrate that edge defects are the most active catalytic sites during hydrazine oxidation electrocatalysis. Theoretical DFT calculations support and explain the mechanism of HzOR on carbon edges, identifying unsaturated graphene armchair defects as the most likely active sites. Finally, these findings explain the 'double peak' voltammetric feature observed on many doped carbons during the HzOR.

  View details for DOI 10.1039/d2cp00213b

  View details for Web of Science ID 000782256900001

  View details for PubMedID 35416204