A Theoretical Investigation of Cu+, Ni2+and Co2+-Exchanged Zeolites for Hydrogen Storage

Özbek, Murat Oluş
İpek Torun, Bahar
This study investigates the H2adsorption on Cu+, Ni2+and Co2+-exchanged SSZ-13 (CHA) and SSZ-39 (AEI) using periodic DFT computations. The most stable Cu+position was found to be the 6-membered-ring window for both zeolites. Similarly, for the investigated Ni2+and Co2+loadings on 6-membered-ring windows, the third nearest neighbor Al positions, i. e., Al−O−Si−O−Si−O−Al coordination, was found to be the most stable position. H2adsorption was investigated for all the Cu+, Ni2+and Co2+centers. AEI and CHA resulted in similar H2−Cu interactions for the Al and B substituted structures. H2adsorption on Cu+located in the 8-membered-ring gave the highest adsorption energy for both frameworks. Replacing Al with B in the framework increased the electron back donation from Cu+(3d) orbitals to H2antibonding orbital (σH2*). The H2adsorption energies on the Ni2+and Co2+-exchanged zeolites were found to be between −15 and −44 kJ/mol. Higher energy values were observed on the AEI framework, especially when two Al atoms have the Al−O−Si−O−Al configuration. Lesser interaction of the d-orbitals in the case of the Co2+and Ni2+cations resulted in heat of H2adsorption close to optimum values required for H2storage on porous materials.


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Citation Formats
M. O. Özbek and B. İpek Torun, “A Theoretical Investigation of Cu+, Ni2+and Co2+-Exchanged Zeolites for Hydrogen Storage,” CHEMPHYSCHEM, vol. 23, no. 20, pp. 202200272–202200272, 2022, Accessed: 00, 2022. [Online]. Available: https://chemistry-europe.onlinelibrary.wiley.com/doi/epdf/10.1002/cphc.202200272.