# Reinforcing the tetracene-based two-dimensional CHsheet by decorating the Li, Na, and K atoms for hydrogen storage and environmental application -A DFT study.
> テトラセン系多孔質炭素シートへのLi・Na・K修飾による水素貯蔵特性のDFT解析


## Abstract

Using density functional theory (DFT), this study examined hydrogen molecule adsorption on zigzag- and armchair-edged tetracene-derived porous carbon sheets (CH sheets) decorated with lithium, sodium, and potassium atoms. On the pristine CH sheet, H₂ adsorption energies at three distinct sites were −0.020, −0.024, and −0.015 eV. Alkali-metal decoration substantially increased adsorption energies; the Li-modified sheet achieved the highest binding energy of −2.070 eV and a maximum H₂ adsorption energy of −0.389 eV. Gravimetric storage capacities for four H₂ molecules reached 7.49 wt% (Li), 7.31 wt% (Na), and 7.14 wt% (K), all exceeding the U.S. Department of Energy target. Mulliken charge analysis indicated electron transfer from the H₂ σ-orbital to the s-orbital of the alkali metals, which accounts for the enhanced binding observed upon decoration.

### Mechanism

Decoration of the carbon sheet with alkali metals (Li, Na, K) promotes electron transfer from the H₂ σ-orbital to the metal s-orbital, increasing adsorption binding energies and enhancing overall hydrogen storage capacity.

## Bibliographic

- **Authors**: Subramani M, Rajamani A, Subramaniam V, Hatshan MR, Gopi S, Ramasamy S
- **Journal**: Environ Res
- **Year**: 2022
- **PMID**: [34571036](https://pubmed.ncbi.nlm.nih.gov/34571036/)
- **DOI**: [10.1016/j.envres.2021.112114](https://doi.org/10.1016/j.envres.2021.112114)
- **Study type**: in vitro study
- **Delivery route**: in vitro
- **Effect reported**: positive

## Delivery context

This is basic research at the cellular or molecular level. For human application, inhalation is the most promising delivery route, but inhalation carries explosion risk and concentration matters (empirical LFL of 10%; high-concentration devices are not recommended).

## Safety notes

This is basic research at the cellular or molecular level. For human application, inhalation is the most promising delivery route, but inhalation carries explosion risk and concentration matters (empirical LFL of 10%; high-concentration devices are not recommended).

See also:
- [Inhalation concentration and LFL / UFL](https://h2-papers.org/en/safety-notes/inhalation-concentration)
- [Consumer Affairs Agency accident cases](https://h2-papers.org/en/safety-notes/accident-cases)
- [Inhalation safety threshold lineage](https://h2-papers.org/en/safety-notes/lineage)

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> **Cite as**: H2 Papers — PMID 34571036. https://h2-papers.org/en/papers/34571036
> **Source**: PubMed PMID [34571036](https://pubmed.ncbi.nlm.nih.gov/34571036/)