Carbon capture and storage, in which CO₂ is selectively removed and sequestrated from flue gas, is a promising strategy to mitigate CO₂ emissions and global warming. Conventionally, CO₂ capture involves an energy-consuming absorbent regeneration step by thermal decomposition (2.0–4.0 GJ ton⁻¹ CO₂), which accounts for the majority (60%–70%) of the total cost. Here, we propose an alternative electrochemical cycle to capture CO₂ in an aqueous alkaline solution, facilitated by the pH swing effect from a proton-coupled electron transfer redox reaction of a biological proton carrier, riboflavin 5′-monophosphate sodium salt hydrate (FMN/FMNH₂). Under lab conditions, an electrolysis cell implementing the FMN proton carrier demonstrates a high energy efficiency, with only 9.8 kJ mol⁻¹ CO₂ captured, which is much lower than traditional approaches using a monoethanolamine absorbent (2.0–4.0 GJ ton⁻¹ CO₂, 88–176 kJ mol⁻¹ CO₂). Thus, this system may contribute toward lowering the cost of CO₂ capture.

碳捕集与封存（其中有选择地从烟气中去除CO ₂并将其隔离）是减轻CO ₂排放和全球变暖的一种有前途的策略。按照惯例，CO ₂捕集涉及通过热分解（2.0–4.0 GJ吨^-1 CO ₂）进行的耗能吸收剂再生步骤，这占总成本的大部分（60％–70％）。在这里，我们提出了一种替代性的电化学循环，用以捕获碱性水溶液中的CO ₂，这是由于生物质子载体核黄素5'-单磷酸钠水合物（FMN / FMNH ₂）。在实验室条件下，采用FMN质子载体的电解池显示出高能效，仅捕获9.8 kJ mol ^-1 CO ₂，这比使用单乙醇胺吸收剂的传统方法（2.0–4.0 GJ ton ^-1 CO _2）低得多。，88–176 kJ mol ^-1 CO ₂）。因此，该系统可以有助于降低CO ₂捕集的成本。