研究論文

Dual-functional materials (DFMs) that can both capture CO₂ and convert it into useful products are attracting growing interest for carbon capture and utilization. However, most existing systems require very high temperatures and oxygen-free conditions, which limits their practical use. In this work, we take a closer look at a Pt–Na/Al₂O₃ DFM that operates at a moderate temperature (350 °C) and can selectively convert CO₂ to CO even in the presence of oxygen.

Using advanced in-situ spectroscopic techniques, we clarify how sodium modifies the electronic state and surface chemistry of platinum, enabling efficient CO formation via hydrogenation. We also identify key reaction intermediates involved in the process. Finally, the material is demonstrated for the first time in an integrated system combining membrane-based direct air capture (m-DAC) with CO₂ conversion. The system shows stable operation with high CO selectivity (up to 93%) and CO concentrations of 1000–2500 ppm, highlighting its potential for practical, air-based CO₂ utilization.