Electrochemical CO2 reduction
Carbon capture and utilization (CCU) is drawing attention around the world as a way to solve the problem of greenhouse gas emissions and increasing energy demands. Among various efforts, the conversion of CO2 into fuels and chemical feedstocks via electrochemical methods is a representative technology of CCU.
We investigate the dynamic phase evolution of Cu-based electrocatalysts during CO2 reduction to elucidate the origin of their activity and selectivity. Using operando soft X-ray microscopy, we revealed the dynamic evolution of cationic Cu species and their role in enhancing C-C coupling activity. We also demonstrated that dilute p-block metal doping (In, Sn) into Cu2O enhances CO2-to-CO conversion efficiency and stability by modulating the electronic structure and stabilizing Cu+ species.
Representative papers
- K. A. Gandionco et al., ACS Applied Materials & Interfaces (2026).
- K. A. Gandionco et al., Nature Synthesis (2026).
- J. Kim et al., Joule (2024).
- K. A. Gandionco et al., Carbon Energy (2023).
Electrochemical NO3- reduction (Nitrate-to-ammonia conversion)
Nitrate (NO3-) contamination in water is a serious environmental issue caused by agricultural and industrial activities. Electrochemical NO3- reduction offers a promising route to simultaneously purify contaminated water and produce ammonia (NH3) under ambient conditions using renewable electricity, replacing the energy-intensive Haber-Bosch process.
We are developing selective and efficient electrocatalysts for the electrochemical conversion of NO3- into NH3.
Source: Discover Chemical Engineering, 3(1), 21 (2023).
Electrochemical reactor engineering (Flow cell, MEA, PSE reactor)
Translating electrocatalysis into industrial processes requires advanced reactor design. A flow cell separates the gaseous reactant from a flowing liquid electrolyte using a gas diffusion electrode, enabling high current density operation. A membrane electrode assembly (MEA) eliminates the liquid catholyte by directly sandwiching an ion exchange membrane between the cathode and anode, minimizing ohmic losses and improving energy efficiency and stability. A porous solid electrolyte (PSE) reactor introduces an additional porous ion-conducting layer between two membranes, enabling the collection of pure products.
We are optimizing these reactor systems to bridge the gap between fundamental research and practical devices.
Source: MetalMat, 1(2), e28 (2024). Nature Catalysis, 5(4), 288-299 (2022).
