A Highly Efficient and Stable Composite of Polyacrylate and Metal–Organic Framework Prepared by Interface Engineering for Direct Air Capture
Mengzhi Guo, Hao Wu, Li Lv, Hong Meng, Jimmy Yun, Junsu Jin, Jianguo Mi
Abstract
We present a kilogram-scale experiment for assessing the prospects of a novel composite material of metal–organic framework (MOF) and polyacrylates (PA), namely NbOFFIVE-1-Ni@PA, for trace CO2 capture. Through the interfacial enrichment of metal ions and organic ligands as well as heterogeneous crystallization, the sizes of microporous NbOFFIVE-1-Ni crystals are downsized to 200–400 nm and uniformly anchored on the macroporous surface of PA via interfacial coordination, forming a unique dual-framework structure. Specifically, the NbOFFIVE-1-Ni@PA composite with a loading of 45.8 wt % NbOFFIVE-1-Ni yields a superior CO2 uptake (ca. 1.44 mol·kg–1) compared to the pristine NbOFFIVE-1-Ni (ca. 1.30 mol·kg–1) at 400 ppm and 298 K, indicating that the adsorption efficiency of NbOFFIVE-1-Ni has been raised by 2.42 times. Meanwhile, the time cost for realizing a complete adsorption/desorption cycle in a fluidized bed has been shortened to 25 min, and the working capacity (ca. 0.84 mol·kg–1) declines only by 1.3% after 2000 cycles. The device is capable of harvesting 2.1 kg of CO2 per kilogram of composite daily from simulated air with 50% relatively humidity (RH). To the best of our knowledge, the excellent adsorption/desorption performances of NbOFFIVE-1-Ni@PA position it as the most advantageous and practically applicable candidate for trace CO2 capture.