First-Principles Study of Hydrogen Storage of Sc-Modified Semiconductor Covalent Organic Framework-1

Abstract

At present, the development of new carbon-based nanoporous materials with semiconductor properties and high hydrogen storage capacity has become a research hotspot in the field of hydrogen storage and hydrogen supply. Here, we pioneered the study of the hydrogen storage capacity of a scandium (Sc) atom-modified semiconductor covalent organic framework-1 (COF-1) layer. It was found that the hydrogen storage capacity of the COF-1 structure was significantly enhanced after the modification of the Sc atom. We found that each Sc atom of the modified COF-1 structure can stably adsorb up to four H 2 molecules, and the average adsorption energy of the four hydrogen molecules is −0.284 eV/H 2 . Six Sc atoms are stably adsorbed most bilaterally on the cell of the COF-1 unit, which can adsorb 24 H 2 molecules in total. In addition, we have further studied the adsorption and desorption behaviors of H 2 molecules on the 6Sc-COF-1 surface at 300 and 400 K, respectively. It can be found that each Sc atom of the COF-1 unit cell can stably adsorb three H 2 molecules with a hydrogen storage performance of 5.23 wt % at 300 K, which is higher than those of lithium-modified phosphorene (4.4 wt %) and lithium-substituted BHNH sheets (3.16 wt %). At 400 K, all of the adsorbed H 2 molecules are released. This confirms the excellent reversibility of 6Sc-COF-1 in hydrogen storage performance. This research has great significance in the application of fuel cells, surpassing traditional hydrogen storage materials.

Recent Advances and Reliable Assessment of Solid‐State Materials for Hydrogen Storage: A Step Forward toward a Sustainable H2 Economy

“…[ 192–194 ] Several theoretical and experimental studies reported enhanced H 2 storage of metal‐doped (Li, Mg, Sc, and Pd) COFs. [ 193,195–197 ] Gao et al. [ 198 ] reported a theoretical H 2 storage of 5 wt% at 300 K and 20 bar using Ca‐intercalated COF containing diphenylethyne units.…”

“…[192][193][194] Several theoretical and experimental studies reported enhanced H 2 storage of metal-doped (Li, Mg, Sc, and Pd) COFs. [193,[195][196][197] Gao et al [198] reported a theoretical H 2 storage of 5 wt% at 300 K and 20 bar using Caintercalated COF containing diphenylethyne units. In another study, at 298 K and 20 bar, Pd-impregnated COF-102 exhibited three folds higher H 2 uptake attributed to the palladium hydride formation and hydrogenation of residual organic compounds.…”

A Bird’s-Eye View on Polymer-Based Hydrogen Carriers for Mobile Applications

“…Even doping the COFs with active metals such as Li does not achieve the required standard in ambient conditions [ 92 ]. An article published recently suggested a hydrogen carrier based on scandium atoms modified with COF-1 [ 93 ]. The reversible hydrogen uptake of this composite was estimated to be 5.23 wt% at 300 K based on molecular dynamics in the CASTEP simulation.…”

Solvothermal synthesis and supercapacitive properties of highly electrochemical stable covalent organic frameworks with triazine building block

“…18 As a special type of conducting polymer with similar covalent structure, COFs can promote electron delocalization and thus exhibit better electrical conductivity. At present, COFs are widely used in gas storage and separation, [19][20][21] heterogeneous catalysis, [22][23][24] sensors, 25-27 semiconductors, 17,28,29 electrochromic [30][31][32] and other fields. Furthermore, COFs are one of the candidates for electrode materials for supercapacitors due to their redox activity with adjustable topological structure and high crystallization.…”