Understanding and mitigating degradation in amine-based sorbents for CO2 direct air capture

[Geoengineering News]

https://www.cell.com/chem/fulltext/S2451-9294(26)00024-0

Authors: Anthony J. Varni, Wade A. Braunecker, Marcos F. Calegari Andrade et al.

26 February 2026

The bigger picture

Atmospheric CO2 removal is no longer a distant goal but an urgent materials challenge. Among emerging strategies, direct air capture (DAC) using amine-based sorbents stands out for its modularity and potential scalability, but material degradation remains a key barrier to long-term deployment. Understanding how and why these materials degrade is essential to making DAC both economically viable and environmentally responsible. This review synthesizes recent progress in uncovering the chemical and physical mechanisms driving sorbent degradation with an emphasis on connecting molecular-level structure and chemistry to macroscopic performance. We highlight foundational discoveries on oxidative and thermal degradation pathways, molecular design strategies that extend sorbent lifetime, and the use of advanced analytical and computational tools for revealing degradation mechanisms with unprecedented detail. Progress in this area directly advances UN Sustainable Development Goals 12 (Responsible Consumption and Production) and 13 (Climate Action) by improving the sustainability and longevity of CO2 capture materials while minimizing chemical waste. Emerging research directions include developing standardized accelerated-aging protocols, applying machine learning to predict and design more robust chemistries, and integrating degradation science with materials-discovery workflows. These innovations will be crucial to achieving DAC systems that operate efficiently and sustainably over decades.

Summary

The success of direct air capture (DAC) of CO2 depends on sorbents that combine high capacity, low energy requirements, and long-term durability. Amine-based sorbents—including solid-supported aminopolymers, grafted amines, and amine-functionalized resins—remain the leading candidates, but their limited lifetimes drive up costs and constrain deployment. In this review, we outline the current understanding of amine-based sorbent degradation with an emphasis on clearly identifying what is known about structure-property-performance relationships, as well as important knowledge gaps. More specifically, we discuss how polymer chemistry, sorbent design variables, and environmental and process conditions contribute to performance loss. In parallel, we outline how advances in spectroscopy, modeling, and accelerated testing are beginning to illuminate chemical and physical degradation mechanisms. Looking forward, we identify future research directions that will be critical for gaining a deeper understanding of degradation, as well as opportunities for developing innovative mitigation strategies for improving the lifetime of amine-based sorbents.

Graphical abstract

Source: Cell Press