# Atom-level interaction design between amines and support for achieving efficient and stable CO2 capture

## TL;DR

A new amine-support system for CO2 capture was developed, offering high efficiency and stability through precise atom-level design.

## Contribution

The novel contribution is the atom-level design of an amine-support system that prevents carbamate dehydration and enhances CO2 capture performance.

## Key findings

- The adsorbent achieved a low regeneration energy of 39.6 kJ/molCO2.
- It showed excellent cyclic stability with only 0.18% decay per cycle.
- The system demonstrated a high CO2 adsorption capacity of 4.0 mmol/g.

## Abstract

Amine-functionalized adsorbents offer substantial potential for CO2 capture owing to their selectivity and diverse application scenarios. However, their effectiveness is hindered by low efficiency and unstable cyclic performance. Here we introduce an amine-support system designed to achieve efficient and stable CO2 capture. Through atom-level design, each polyethyleneimine (PEI) molecule is precisely impregnated into the cage-like pore of MIL–101(Cr), forming stable composites via strong coordination with unsaturated Cr acid sites within the crystal lattice. The resulting adsorbent demonstrates a low regeneration energy (39.6 kJ/molCO2), excellent cyclic stability (0.18% decay per cycle under dry CO2 regeneration), high CO2 adsorption capacity (4.0 mmol/g), and rapid adsorption kinetics (15 min for saturation at 30 °C). These properties stem from the unique electron-level interaction between the amine and the support, effectively preventing carbamate products’ dehydration. This work presents a feasible and promising cost-effective and sustainable CO2 capture strategy.

An amine-support system has been introduced through atom-level design, achieving low regeneration energy, excellent cyclic stability, high capacity, and rapid kinetics, stemming from electron-level interactions preventing carbamate dehydration.