Summary

• The dominant development is a lab-scale aqueous carbon-capture material that targets bicarbonate in water rather than gaseous CO2 directly.
• Guanidinium chemistry appears to outperform conventional amine motifs for bicarbonate binding in the tested aqueous setting.
• Mild pH-swing regeneration is a stable operational feature across the material reports, reducing the need for harsh regeneration conditions.
• Repeated cycling is a major signal: performance improves after initial runs and remains active through at least 13 adsorption-desorption cycles in model solutions.
• Salt tolerance is present but limited, with measurable capture retained in NaCl-rich mixtures and reduced performance as chloride concentration rises.
• The evidence is tightly coherent and mostly pre-commercial, with little sign of policy or market activity in this snapshot.
• The topic looks structural rather than short-lived because it sits within broader carbon removal and carbon management research.