Publications

Translation between molecular, material, process, and systems in developing separation technologies
Publications

For the most up-to-date publication list, please see Holmes' Google Scholar

Diagram of process systems engineering components, including sorbent selection, heat integration and water management, and assessment of technological viability

15. Process systems engineering: a key enabler of adsorption-based direct air capture
Holmes, H. E.; Kim, J.; Realff, M. J. 
Current Opinion in Chemical Engineering 2025, 51, 101202.

Water plays a large role in direct air capture cost and energy

14. Two keys to scalable direct air capture: water management and contactor productivity
Kim, S. K.; Holmes, H. E.; Realff, M. J.; Jones, C. W.; Lively, R. P.
Current Opinion in Chemical Engineering 2025, 50, 101198. 

Electrocatalysis is used to traverse the nitrogen oxidation state ladder, where each oxidation state has a unique use as a fuel or consumer product. Electrochemical separations and reactive electrochemical separations are also used to traverse this nitrogen ladder.

13. Electrochemical Reactive Separations Enable Electrified Nitrogen Manufacturing and Remediation 
Holmes, H. E.; Guo, J.; Miller, D.; Tarpeh, W. A.
Current Opinion in Electrochemistry 2025, 54, 101760.

XRF maps of strong-base and weak-base hybrid anion exchange resins in varying wastewater types. They look like spheres with varying color intensities indicating varying phosphorus and sulfur concentrations

12. Probing the Mechanism of Selective Phosphate Adsorption from Wastewater using Aqueous and Synchrotron X-ray Characterization 
Sharma, N.*; Apraku, E.*; Holmes, H. E.*; Gong, M.; Bustamante, D.; Weker, J.; Bone, S.; Tarpeh, W. A.
Journal of the American Chemical Society 2025, 147 (33), 30475 - 30489 

Different forms of carbon negative technologies and how they interact with environment

11. Navigating the Obstacles of Carbon-Negative Technologies
Ho, D. T.; Lamers, P.; Nawaz, S.; Sugiyama, M.; Carolina Oliveira Fiorini, A.; Yu, Z.; Holmes, H. E.; Gadikota, G.; Breyer, C.; Macintosh, A.; Butner, D.;  Waschka, M.; Evans, M. C. 
One Earth 2024, 7 (9), 1471 – 1476

Polyamines with varying amounts of primary, secondary, and tertiary amine are used to create varying CO2 performance metrics, which then impact the cost and carbon footprint of the direct air capture process

10. Tuning Sorbent Properties to Reduce the Cost of Direct Air Capture
Holmes, H. E.*; Banjeree, S.*; Vallace, A.; Zhang, X.; Lee, W. H.; Lively, R. P.; Jones, C. W.; Realff, M. J. 
Energy & Environmental Science 2024, 17, 4544 – 4559 

A polymer network containing guanidine groups that are interacting with CO2 and H2O

9. Guanidine-Functionalized PIM-1 as a High-Capacity Polymeric Sorbent for CO2 Capture 
Roy, A.*; Holmes, H. E.*; Baugh, L.; Calabro, D.; Leisen, J.; Seth, S.; Ren, Y.; Weston, S. C.; Lively, R. P.; Finn, M.G.  
Chemistry of Materials 2024, 36 (9), 4393 – 4402 

A direct air capture device is 3D printed from a sorbent-loaded ink

8. Cold Temperature Direct Air CO2 Capture with Amine-Loaded Metal-Organic Framework Monoliths 
Wang, Y.; Rim, G.; Song, M.; Holmes, H. E.; Jones, C. W.; Lively, R. P.
ACS Applied Materials & Interfaces. 2024, 16 (1), 1404 – 1415 

Water and CO2 pass through a carbon capture system with a heat integration scheme implemented. Water and heat are shown to play important roles.

7. Water Management and Heat Integration in Direct Air Capture Systems
Holmes, H. E., Realff, M. J., Lively, R. P. 
Nature Chemical Engineering 2024, 1, 208-215 

A 3D printed gyroid, with an external cube shape and internal gyroid pattern. The gyroid walls are porous and contain CO2 adsorbents.

6. Polymer-Sorbent Direct Air Capture Contactors with Complex Geometries 3D-Printed via Templated Phase Inversion
Kim, S.-Y.; Holmes, H. E.; Wang, Y.; Weston, S. C.; Lively, R. P. 
One Earth 2024, 7 (9), 1471 – 1476

There is an optimum relative humidity at 30% where CO2 uptake is highest, due to adsorption on two amine sites instead of one.

5. Optimum Relative Humidity Enhances CO2 Uptake in Diamine-Appended M2(dobpdc) 
Holmes, H. E.; Ghosh, S.; Li, C.; Kalyanaraman, J.; Realff, M. J.; Weston, S. C.; Lively, R. P 
Chemical Engineering Journal 2023, 477, 147119  

Biomass combustion produces flue gas with CO2 and other contaminants. These contaminants can cause adsorbent degradation, including poisoning and fouling. This is depicted by sorbent gravestones with cause of death, or degradation, written on the face.

4. Evaluating Degradation of CO2 Adsorbents in Flue Gas from Bioenergy with Carbon Capture and Storage
Holmes, H. E.; Schreck, R. D.; Ghosh, S.; Sun, W.; Realff, M. J. Lively, R. P. 
Sustainable Energy & Fuels 2023, 7 (18), 4602 – 4607 

Hollow fiber sorbents are formed by extruding a MOF/polymer solution into a quench batch and then taking the fibers up on a drum, followed by solvent exchange and amine infusion

3. Scalable Formation of Diamine-Appended Metal-Organic Framework Hollow Fiber Sorbents for Post-Combustion CO2 Capture 
Quan, W.; Holmes, H. E.; Zhang, F.; Hamlett, B. L.; Finn, M. G.; Abney, C. W. Kapelewski, M. T.; Weston, S. C.; Lively, R. P.; Koros, W. J. 
JACS Au 2022, 2 (6), 1350 – 1358 

Biomass and water are fed to boiler, producing steam that generates electricity. CO2-rich flue gas is also produced, which passes over solid adsorbent columns that separate CO2 from N2 and O2.

2. Defining Targets for Adsorbent Material Performance to Enable Viable BECCS Processes
Holmes, H. E.; Lively, R. P.; Realff, M. J. 
JACS Au 2021, 1 (6), 795 - 806 

Mechanism for CO2 reduction

1. Potential Dependence of the Local pH in a CO2 Reduction Electrolyzer 
Henckel, D. A.; Counihan, M. J.; Holmes, H. E.; Chen, X.; Nwabara, U. O.; Verma, S.; Rodríguez-López, J.; Kenis, P. J. A.; Gewirth, A. A. 
ACS Catalysis 2021, 11 (1), 255 – 263. 

Holmes Google Scholar