Energy Environment
Solution Laboratory

Laser processing has emerged as a powerful platform for engineering electrocatalyst surfaces and interfaces with exceptional spatial and temporal precision. Unlike conventional synthesis routes that largely access equilibrium structures, laser irradiation can generate non-equilibrium phases, defect-rich microstructures, and dynamically engineered interfaces through localized energy delivery and ultrafast quenching. These unique capabilities offer new opportunities for tailoring catalytic activity and selectivity in electrochemical CO₂ and CO reduction. This review summarizes recent advances in laser-engineered electrocatalysts, with emphasis on the fundamental principles of laser–matter interactions and fabrication strategies including pulsed laser deposition, direct laser writing, and pulsed laser ablation in liquids. We discuss how laser parameters govern surface restructuring, oxidation-state modulation, defect formation, and interfacial engineering, enabling the creation of structured electrodes, oxide–metal interfaces, and surfactant-free nanomaterials. Representative catalyst systems are highlighted to illustrate the impact of laser-induced modifications on catalytic performance and reaction pathways. Although the application of laser processing in CO₂ and CO electrocatalysis remains relatively underexplored, its ability to simultaneously control morphology, composition, and electronic structure positions it as a promising platform for next-generation catalyst design. Finally, current challenges and future opportunities are discussed, including mechanistic understanding, operando characterization, parameter standardization, and scalable manufacturing. We anticipate that laser processing will evolve beyond a surface-modification tool toward a versatile platform for non-equilibrium electrocatalyst design and sustainable energy-conversion technologies.

Interface engineering of silver (Ag) electrodes provides an effective strategy to tune activity and selectivity in electrochemical CO₂ reduction (CO₂RR). Here, Ag and Ag oxide (Ag/AgxO) electrodes were prepared via controlled infrared (1064 nm) laser treatment and evaluated in KHCO₃ and phosphate electrolytes. Laser-induced surface restructuring modified oxidation states, crystallographic orientations, and interfacial electronic properties, leading to electrolyte- and potential-dependent shifts in product distribution. In KHCO₃ electrolyte, CO remained the dominant product, whereas phosphate electrolyte significantly enhanced CO selectivity with increasing laser treatment. Oxidized Ag surfaces suppressed hydrogen, formate, and C₂₊ hydrocarbons. Product selectivity showed clear potential dependence: CO and C₂₊ hydrocarbons peaked at moderate potentials, while formate formation increased at more negative potentials. Long-chain C₂₊ hydrocarbons followed a Fischer-Tropsch-like growth trend. Electrochemical impedance spectroscopy revealed changes in charge-transfer kinetics and interfacial capacitance. Density functional theory calculations indicate that CO formation via COOH intermediates is favored on Ag(111) and Ag₂O(111), whereas formate formation via HCOO* is more favorable on metallic Ag. These results clarify how Ag/Ag oxide interfaces regulate CO₂RR pathways.