Preparation of thermally reduced heteroatom (N, S, and N-S) doped graphene oxides modified with gold nanoparticles for use as ethylene glycol oxidation catalysts
SURFACES AND INTERFACES, cilt.58, 2025 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 58
- Basım Tarihi: 2025
- Doi Numarası: 10.1016/j.surfin.2025.105788
- Dergi Adı: SURFACES AND INTERFACES
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Eskişehir Osmangazi Üniversitesi Adresli: Evet
Özet
In this study, the preparation of catalyst materials for ethylene glycol (EG) fuel cell has been investigated by combining 1-octanethiol-capped gold (Au) nanoparticles with heteroatom-doped reduced graphene oxides (rGOs). Nitrogen (N), sulfur (S), and both nitrogen-sulfur (NS) doped rGOs, as well as undoped were prepared by a thermal reduction method using urea, sodium bisulfite, and thiourea as heteroatom sources. The reduction of GO to rGO was confirmed using XRD analysis, and effective heteroatom doping of rGO was verified through Raman, EDX, XPS, and FTIR analyses. 1-octanethiol was used as a capping agent to increase the stability and improve the dispersion of Au nanoparticles. The average size of Au nanoparticles was determined to be 3.07 +/- 0.75 nm by TEM analysis. EG oxidation on Au@NrGO(1:2), Au@NSrGO(1:2), Au@SrGO(1:2), and Au@rGO catalysts resulted in current densities; 50.70 mA cm- 2, 38.50 cm- 2, 32.15 cm- 2, and 26.37 cm- 2, respectively, indicating the heteroatom doping of rGO significantly improved the catalytic activity. Among all the prepared nanocomposites, Au@NrGO exhibited the highest response and stability in EG oxidation, attributed to the high performance of NrGO as a support material and the role of 1-octanethiol as a capping agent. Ion-exclusion chromatography analysis revealed the formation of oxalate, glycolate, formate, and acetate during the electrochemical oxidation of EG under the specified conditions. Finally, it can be concluded that thermal reduction is a very effective method for the reduction and heteroatom doping of rGOs, leading to high activity in direct alcohol fuel cells.