Effect of structural defects on the hydrogen adsorption in promising nanostructures

Importance of Van der Waals Interactions in Hydrogen Adsorption on a Silicon-carbide Nanotube Revisited with vdW-DFT and Quantum Monte Carlo

“…This has motivated further investigations into doping schemes with dopants such as alkali and transition metals 12,14 or with vacancies. 11,15 These studies, however, did not incorporate van der Waals (vdW) corrections into the conventional DFT scheme, and thus they may have underestimated the true adsorption potential. From another viewpoint, the basis sets adopted for DFT calculations also matter, since Gaussian and numerical basis sets can give rise to overestimated interaction energies owing to the basis set superposition error.…”

“…Silicon-carbide nanotubes (SiCNTs) are a typical nanostructure studied for the above purpose owing to their enhanced molecular interactions compared with those of the structurally related (and more common) carbon nanotubes (CNTs). This feature has been linked to the SiCNT polarized surface originating from the Si–C bonds. − Despite this, density functional studies based on local (LDA), semilocal (GGA), and hybrid (B3LYP) exchange-correlation (XC) functionals on pristine nanotubes estimated the adsorption energy of hydrogen between 0.7 and 1.98 kcal/mol, − which is still too small for storing hydrogen at the desired ambient temperature. This has motivated further investigations into doping schemes with dopants such as alkali and transition metals , or with vacancies. , These studies, however, did not incorporate van der Waals (vdW) corrections into the conventional DFT scheme, and thus they may have underestimated the true adsorption potential.…”

Importance of van der Waals interactions in hydrogen adsorption on a silicon-carbide nanotube revisited with vdW-DFT and quantum Monte Carlo

“…Silicon-carbide nanotubes (SiCNTs) are a typical nanostucture studied for the above purpose [6,7,8,9] owing to their enhanced molecular interactions compared with that of the structurally related (and more common) carbon nanotubes. This feature has been linked to the SiCNT polarized surface originating from the Si-C bonds [10,11,12,13].…”

“…Despite this, studies have suggested that in the pristine state, the adsorption energy of hydrogen on SiCNTs still lies below the required values, ranging between 0.7 and 1.98 kcal/mol. This has motivated further investigations into doping schemes with dopants such as al-kali and transition metals [8,14] or with vacancies [7,15]. These studies, however, did not incorporate van der Waals (vdW) corrections into the conventional DFT scheme, and thus they may have underestimated the true adsorption potential.…”

Theoretical Investigation of H2 Interactions on ZnO Cluster: DFT Approach

“…5,6 ZnO is also a hydrogen sensing material and the sensing mechanism involves the process of chemisorption. 7 When the hydrogen comes in contact with the sensing material, there are three possibilities of contact of hydrogen with the ZnO sensing material. They are Zn, Zn-O bridge or O.…”