Hydrogen Storage, Magnetism and Electrochromism of Silver Doped FAU Zeolite: First-Principles Calculations and Molecular Simulations

Abstract

The complex configuration, H2 adsorption binding energy, magnetic, and optical properties of FAU zeolites with Ag cations loaded by ion exchange in the vacant dielectric cavities were investigated by employing the first-principles calculations with all-electron-relativistic numerical atom-orbitals scheme and the Metropolis Monte Carlo molecular simulations. The visible absorption spectrum peaked at distinct wavelengths arranging from red or green to blue colors when changing the net charge load, due to the produced various redox states of Ag cations exchanging at multiple Li+-substituted sites. The spin population analyses indicate the ferrimagnetic coupling between Al–O–Si framework and Ag cations originates from the major ferromagnetic spin polarization in Ag cation cluster coordinating with sodalite cages, with the net spins appreciably depending on the Ag content and exchange site. The H2 adsorption capacities and binding energies represent significant dependence on the content, location, and electronic property of Ag cations introduced into the FAU zeolites. The evident decrease of H2 adsorption binding energy with increased loading concentration demonstrates repulsive interaction between H2 molecules and heterogeneous adsorption configuration on Ag cations. The adsorption sites of H2 sorted by the binding energy with different adsorption configurations were correlated with exchange sites of Ag cations under different Ag loading to comprehend the H2 adsorption mechanism.

A Prussian blue analog-based copper–aluminum layered double hydroxide for cesium removal from water: fabrication, density functional theory-based molecular modeling, and the adsorption mechanism

“…The computational results indicate that the binding energy of Cs + in the crystal structure is negative, suggesting that Cs + can be spontaneously captured in the presence of interstitial spaces. 50 The binding energy of Cs + is constant at around À3.5434 eV for different interstitial spaces positions in the structure. In contrast, the binding energy of K + is relatively unstable, with positive values for all but a few sites, indicating that the defect sites of PB have not been fully occupied by K + (Fig.…”

Hydrogen production, transportation, utilization, and storage: Recent advances towards sustainable energy

“…Zeolites are microporous and crystalline aluminosilica-based materials with good surface area and porosity characteristics for the general storage of non-polar gases [337,361]. Their 3D structures contain tetrahedral primary building units which in turn determine the size of the channels and cages in which hydrogen can be stored [362].…”

Impact of Polymers on Magnesium-Based Hydrogen Storage Systems

“…Hydrogen energy is considered an efficient energy carrier for present and future energy needs. Hydrogen energy has been considered a primary alternative to replace fossil fuels, where it can be utilized as a fuel for automobiles and provide heat/electricity for industries and households [4][5][6]. The researchers recognize that hydrogen energy possesses numerous advantages, such as…”