Tailoring an energy-efficient carbon breathing paper by rigid-flexible interlocking for life support systems

Designing an energy-saving carbon breathing paper offers the substantial potential for life support systems owing to its effective removal of low-level CO 2 . Here, an energy-saving carbon breathing paper was tailored by the rigid-flexible interlocking of cellulose molecules with polyethyleneimine and poly-N-isopropylacrylamide. Abundant amino groups (14.98 mmol/g) on paper could capture CO 2 (6.47 mmol/g) to form carbamic acid, which further generated the difficult-to-decompose urea through dehydration and nucleophilic addition reactions, leading to higher regeneration temperature. Interestingly, the excellent temperature sensitivity of the paper endows stretch-to-shrink molecular state transitions, increased the amino surface electrostatic potential, passivated nucleophilic addition activity and regulated carbamic acid towards thermal decomposition, effectively reduced regeneration temperature to 55 °C. More encouragingly, water, which is rich in paper, prevented the formation of urea, improving the cycle stability in extreme environments, such as high temperatures and pure CO 2 atmosphere. The result of 30.67 % life extension in mice in confined spaces indicates that the TCBP is a promising candidate for cost-effective carbon removal of life support systems.