Direct observation of ammonia storage in UIO-66 incorporating Cu(II) binding sites

DOI: 10.1021/jacs.2c00952

Authors: Yujie Ma (University of Manchester) , Wanpeng Lu (University of Manchester) , Xue Han (University of Manchester) , Yinlin Chen (University of Manchester) , Ivan Da Silva (ISIS Facility) , Daniel Lee (University of Manchester) , Alena M. Sheveleva (University of Manchester) , Zi Wang (University of Manchester) , Jiangnan Li (University of Manchester) , Weiyao Li (University of Manchester) , Mengtian Fan (University of Manchester) , Shaojun Xu (University of Manchester; UK Catalysis Hub, Research Complex at Harwell; Cardiff University) , Floriana Tuna (University of Manchester) , Eric J. L. Mcinnes (University of Manchester) , Yongqiang Cheng (Oak Ridge National Laboratory) , Svemir Rudic (ISIS Facility) , Pascal Manuel (ISIS Facility) , Mark D. Frogley (Diamond Light Source) , Anibal J. Ramirez-Cuesta (Oak Ridge National Laboratory) , Martin Schroeder (University of Manchester) , Sihai Yang (University of Manchester)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Journal Of The American Chemical Society

State: Published (Approved)
Published: May 2022
Diamond Proposal Number(s): 19850

Abstract: The presence of active sites in metal–organic framework (MOF) materials can control and affect their performance significantly in adsorption and catalysis. However, revealing the interactions between the substrate and active sites in MOFs at atomic precision remains a challenging task. Here, we report the direct observation of binding of NH3 in a series of UiO-66 materials containing atomically dispersed defects and open Cu(I) and Cu(II) sites. While all MOFs in this series exhibit similar surface areas (1111–1135 m2 g–1), decoration of the −OH site in UiO-66-defect with Cu(II) results in a 43% enhancement of the isothermal uptake of NH3 at 273 K and 1.0 bar from 11.8 in UiO-66-defect to 16.9 mmol g–1 in UiO-66-CuII. A 100% enhancement of dynamic adsorption of NH3 at a concentration level of 630 ppm from 2.07 mmol g–1 in UiO-66-defect to 4.15 mmol g–1 in UiO-66-CuII at 298 K is observed. In situ neutron powder diffraction, inelastic neutron scattering, and electron paramagnetic resonance, solid-state nuclear magnetic resonance, and infrared spectroscopies, coupled with modeling reveal that the enhanced NH3 uptake in UiO-66-CuII originates from a {Cu(II)···NH3} interaction, with a reversible change in geometry at Cu(II) from near-linear to trigonal coordination. This work represents the first example of structural elucidation of NH3 binding in MOFs containing open metal sites and will inform the design of new efficient MOF sorbents by targeted control of active sites for NH3 capture and storage.

Journal Keywords: Adsorption; Metal organic frameworks; Electron paramagnetic resonance spectroscopy; Molecules; Defects

Subject Areas: Chemistry, Materials


Instruments: B18-Core EXAFS , B22-Multimode InfraRed imaging And Microspectroscopy

Added On: 11/05/2022 08:49

Documents:
jacs.2c00952.pdf

Discipline Tags:

Chemistry Materials Science Metal-Organic Frameworks Metallurgy Organometallic Chemistry

Technical Tags:

Spectroscopy Infrared Spectroscopy X-ray Absorption Spectroscopy (XAS) Synchtron-based Fourier Transform Infrared Spectroscopy (SR-FTIR)