Thermal Activation of a Copper-Loaded Covalent Organic Framework for Near-Ambient Temperature Hydrogen Storage and Delivery

Journal Article · 31 January 2020 · ACS Materials Letters

DOI: https://doi.org/10.1021/acsmaterialslett.9b00413 · OSTI ID:1600127

Braunecker, Wade A.  ^[1]; Shulda, Sarah ^[2]; Martinez, Madison B. ^[1]; Hurst, Katherine E.  ^[2]; Koubek, Joshua T. ^[3]; Zaccarine, Sarah ^[3]; Mow, Rachel  ^[1]; Pylypenko, Svitlana ^[1]; Sellinger, Alan ^[1]; Gennett, Thomas ^[1]; Johnson, Justin C  ^[4]

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1. National Renewable Energy Lab. (NREL), Golden, CO (United States); Colorado School of Mines, Golden, CO (United States)
2. National Renewable Energy Lab. (NREL), Golden, CO (United States)
3. Colorado School of Mines, Golden, CO (United States)
4. National Renewable Energy Laboratory (NREL), Golden, CO (United States)

Copper(II) formate is efficiently incorporated into the pores of a 2D imine-based covalent organic framework (COF) via coordination with the phenol and imine groups. The coordinated metal ion is then reduced to Cu(I) with a thermal treatment that evolves CO₂. After loading with hydrogen gas, the majority of H₂ desorbs from the coordinatively saturated Cu(II) COF at temperatures < -100 degrees C. However, the activated Cu(I) COF retains adsorbed H₂ above room temperature. Adsorption/desorption of H₂ was highly reversible. Diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) strongly supports a molecular hydrogen interaction with Cu(I). A Kissinger analysis of variable ramp rate desorption experiments estimates the enthalpy of H₂ desorption from Cu(I) at 15 kJ mol^-1. The results represent an advance toward practical H₂ storage and delivery in a lightweight, stable, and highly versatile material.

• Research Organization: National Renewable Energy Laboratory (NREL), Golden, CO (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Fuel Cell Technologies Program (EE-3F)
• Grant/Contract Number: AC36-08GO28308
• OSTI ID: 1600127
• Report Number(s): NREL/JA-5900-74789
• Journal Information: ACS Materials Letters, Journal Name: ACS Materials Letters Journal Issue: 3 Vol. 2; ISSN 2639-4979
• Publisher: ACS PublicationsCopyright Statement
• Country of Publication: United States
• Language: English