Yuxuan Chen

All Publications

• Membrane-free electrochemical production of acid and base solutions capable of processing ultramafic rocks. Nature communications Charnay, B. P., Chen, Y., Misleh, J. W., Wright, J. G., Agarwal, R. G., Sauvé, E. R., Toh, W. L., Surendranath, Y., Kanan, M. W. 2025; 16 (1): 9759

  Abstract

  Electrochemical production of acid and base from water enables their use as regenerable reagents in closed-loop processes, with attractive applications including CO2 capture or mineralization and low-temperature production of Ca(OH)2. Conventional systems utilize ion exchange membranes (IEMs) to inhibit H+/OH- recombination, which leads to high resistive losses that compromise energy efficiency and poor tolerance for polyvalent metal ions that complicates applications involving mineral resources. Here we use ion transport modeling to guide the design of a system that uses a simple porous separator instead of IEMs. Using H2 redox reactions for H+/OH- production, we demonstrate acid-base production at useful concentrations in the presence of polyvalent impurities with lower energy demand and higher current density than reported IEM-based systems. Cells can be stacked by combining H2 electrodes into a bipolar gas diffusion electrode, which recirculates H2 with near-unity efficiency. We show that the cell outputs extract alkalinity from olivine and serpentine as Mg(OH)2 and Mg3Si2O6(OH)2, which remove CO2 from ambient air to form Mg carbonates. These studies establish the principles for membrane-free electrochemical acid-base production, enabling closed-loop resource recovery and material processing powered by renewable electricity.

  View details for DOI 10.1038/s41467-025-64595-5

  View details for PubMedID 41193486

  View details for PubMedCentralID 10722509

• Thermal Ca2+/Mg2+ exchange reactions to synthesize CO2 removal materials. Nature Chen, Y., Kanan, M. W. 2025

  Abstract

  Most current strategies for carbon management require CO2 removal (CDR) from the atmosphere on the multi-hundred gigatonne (Gt) scale by 2100 (refs. 1-5). Mg-rich silicate minerals can remove >105 Gt CO2 and sequester it as stable and innocuous carbonate minerals or dissolved bicarbonate ions3,6,7. However, the reaction rates of these minerals under ambient conditions are far too slow for practical use. Here we show that CaCO3 and CaSO4 react quantitatively with diverse Mg-rich silicates (for example, olivine, serpentine and augite) under thermochemical conditions to form Ca2SiO4 and MgO. On exposure to ambient air under wet conditions, Ca2SiO4 is converted to CaCO3 and silicic acid, and MgO is partially converted into a Mg carbonate within weeks, whereas the input Mg silicate shows no reactivity over 6 months. Alternatively, Ca2SiO4 and MgO can be completely carbonated to CaCO3 and Mg(HCO3)2 under 1 atm CO2 at ambient temperature within hours. Using CaCO3 as the Ca source, this chemistry enables a CDR process in which the output Ca2SiO4/MgO material is used to remove CO2 from air or soil and the CO2 process emissions are sequestered. Analysis of the energy requirements indicates that this process could require less than 1 MWh per tonne CO2 removed, approximately half the energy of CO2 capture with leading direct air capture technologies. The chemistry described here could unlock Mg-rich silicates as a vast resource for safe and permanent CDR.

  View details for DOI 10.1038/s41586-024-08499-2

  View details for PubMedID 39972128

• Hypophosphite addition to alkenes under solvent-free and non-acidic aqueous conditions. Chemical communications (Cambridge, England) Huang, Z., Chen, Y., Kanan, M. W. 1800

  Abstract

  Hypophosphite adds to alkenes in high yields under solvent-free conditions at elevated temperature, including alpha,beta-unsaturated carboxylates. The reaction proceeds by a radical mediated pathway. Hypophosphite addition is also effective under non-acidic aqueous conditions employing radical initiators. These methods complement other hypophosphite addition reactions and simplify the synthesis of polyfunctional H-phosphinates.

  View details for DOI 10.1039/d1cc06831h

  View details for PubMedID 35060983

• Electro-Descriptors for the Performance Prediction of Electro-Organic Synthesis ANGEWANDTE CHEMIE-INTERNATIONAL EDITION Chen, Y., Tian, B., Cheng, Z., Li, X., Huang, M., Sun, Y., Liu, S., Cheng, X., Li, S., Ding, M. 2021; 60 (8): 4199-4207

  Abstract

  Electrochemical organic synthesis has attracted increasing attentions as a sustainable and versatile synthetic platform. Quantitative assessment of the electro-organic reactions, including reaction thermodynamics, electro-kinetics, and coupled chemical processes, can lead to effective analytical tool to guide their future design. Herein, we demonstrate that electrochemical parameters such as onset potential, Tafel slope, and effective voltage can be utilized as electro-descriptors for the evaluation of reaction conditions and prediction of reactivities (yields). An "electro-descriptor-diagram" is generated, where reactive and non-reactive conditions/substances show distinct boundary. Successful predictions of reaction outcomes have been demonstrated using electro-descriptor diagram, or from machine learning algorithms with experimentally-derived electro-descriptors. This method represents a promising tool for data-acquisition, reaction prediction, mechanistic investigation, and high-throughput screening for general organic electro-synthesis.

  View details for DOI 10.1002/anie.202014072

  View details for Web of Science ID 000601056900001

  View details for PubMedID 33180375