First-principles DFT Insights into the Adsorption of Hydrazine on Bimetallic β1-NiZn Catalyst: Implications for Direct Hydrazine Fuel Cells - data

We present a systematic first-principles density functional theory study with dispersion corrections (DFT-D3) of hydrazine adsorption on the experimentally observed (111), (110) and (100) surfaces of the binary β₁-NiZn alloy. A direct comparison has been drawn between the bimetallic and monometallic Ni and Zn counterparts to understand the synergistic effect of alloy formation. The hydrazine adsorption mechanism has been characterised through adsorption energies, Bader charges, the d-band centre model, and the coordination number of the active site - which is found to dictate the strength of the adsorbate-surface interaction.  The bimetallic β₁-NiZn nanocatalyst is found to exhibit higher activity towards adsorption and activation of hydrazine compared to the monometallic Ni and Zn counterparts. The Ni-sites of the bimetallic NiZn surfaces are found to be generally more reactive than Zn sites, which is suggested to be due to the higher d-band centre of -0.13 eV (closer to the Fermi level), forming higher energy anti-bonding states through Ni-N interactions. The observed synergistic effects derived from surface composition and electronic structure modification from Ni and Zn alloying should provide new possibilities for the rational design and development of low-cost bimetallic Ni-Zn alloy catalysts for direct hydrazine fuel cell (DHFC) applications.

The data underpinning the research are available in the .xlsx format (can be viewed either by MS Office or Libre Office) comprising 7 datasheets which gives information about the bulk structure of monometallic Ni and Zn and bimetallic NiZn; hydrazine (N2H4) adsorption structures adsorption Ni(111), Zn(001), NiZn(111), NiZn(110) and NiZn(100) surfaces. Data for the optimized structures are available in CONTCAR format of the VASP simulation program. The CONTCAR files consist of lattice parameter and atomic positions and can be viewed either by MS Office or WordPad and displayed using VESTA software.

Research results based upon these data are published at http://doi.org/10.17035/d.2020.0115779666