Proton trap engineered electric swing adsorption for scalable and cost-effective direct air capture

[Geoengineering News]

https://www.nature.com/articles/s41467-026-75916-7

Authors: Yao Shen, Kai Pang, Weichen Zhao, Liang Chen, Jingkai Zhao, Jiexu Ye, Beini Zhang, Sujing Li, Wei Li, Zhen Xu, Jing Meng, Xiang Gao & Shihan Zhang 

21 July 2026

Abstract

Direct air capture (DAC) is critical to achieve carbon neutrality, yet current technologies face significant barriers to widespread, cost-effective deployment. Amine-based electric swing adsorption (ESA) offers a promising low-energy, steam-free pathway, but its efficiency is fundamentally limited by an inherent 2:1 amine-to-CO2 stoichiometric penalty. Here, we overcome this bottleneck by engineering a point defect-mediated proton trapping network into ESA sorbents, enabling a 1:1 amine-CO2 stoichiometry. Our engineered sorbent achieves a CO2 uptake of 6.57 mmol g−1 from 400 ppm CO2, a 28.8% improvement over the state-of-the-art sorbents. Regeneration is achieved with a low energy input of 3.4 GJ t−1 and exhibits a CO2 release rate 48% faster than conventional thermal methods. N5-dGA remains stable under 0-80% relative humidity fluctuations and at a gas velocity of 1 m s−1. Techno-economic analysis projects DAC operating costs of $48-62 t−1 using renewable electricity, up to 78% lower than temperature swing adsorption DAC and below the $100 t−1 CO2 target. This work presents a sorbent design and ESA process, establishing a scientifically rigorous and economically viable pathway towards gigaton-scale DAC deployment.

Source: Nature Communications