Modeling of H2O, H2O2, and H2O3 formation mechanisms on graphene oxide (GO) surfaces
| Autor: | Hector Gomez, Michael N. Groves |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Reaction mechanism
Hydrogen Chemistry Oxide chemistry.chemical_element 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology Photochemistry 01 natural sciences 0104 chemical sciences Catalysis chemistry.chemical_compound General Materials Science Density functional theory Singlet state Triplet state 0210 nano-technology Ground state |
| Zdroj: | Carbon. 177:252-259 |
| ISSN: | 0008-6223 |
| DOI: | 10.1016/j.carbon.2021.02.053 |
| Popis: | The role of O 2 gas on graphene oxide (GO) surfaces is an area of great interest for heterogeneous catalytic materials in ambient and interstellar conditions. As a result, we investigated the transfer mechanisms of surface hydrogens from OH groups on the basal plane of GO using density functional theory. The reaction mechanisms were calculated in both triplet and singlet states due to the ground state spin states of O 2 and the products. By passing O 2 gas over GO, we found H 2 O , H 2 O 2 , and H 2 O 3 (singlet state) were generated products. In reference to triplet O 2 , we found that H 2 O was produced exothermically, with differences in energy of −0.423 eV and −0.048 eV in the triplet and singlet states, respectively. The triplet state is favored in H 2 O formation since the O 2 acted as a hydrogen shuttle and transported an H-atom from one OH group to the other. H 2 O 2 and H 2 O 3 formation occurred endothermically, requiring 1.08 eV and 0.978 eV in the singlet state, respectively. Additionally, H 2 O 2 in the triplet state resulted in a net energy difference of 2.22 eV. Based on these calculations, GO is a highly unfavorable catalyst for H 2 O 2 formation on the basal plane and is thermodynamically inclined to form H 2 O . |
| Databáze: | OpenAIRE |
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