Nano-Pd-decorated electrochemically exfoliated graphene oxide as catalyst layers in direct ethanol fuel cells
MATERIALS CHEMISTRY AND PHYSICS, cilt.346, 2025 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 346
- Basım Tarihi: 2025
- Doi Numarası: 10.1016/j.matchemphys.2025.131339
- Dergi Adı: MATERIALS CHEMISTRY AND PHYSICS
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Chimica, Compendex, INSPEC
- Eskişehir Osmangazi Üniversitesi Adresli: Evet
Özet
This study investigates the preparation of electrochemically exfoliated graphene oxides (EEGOs) as alternative support materials for palladium (Pd) catalysts that can be used in direct ethanol fuel cells. The performance of EEGOs was compared to that of conventional Vulcan carbon black (VC) and chemically synthesized graphene oxide (GO). EEGOs were prepared in three different supporting electrolyte (Na2SO4, (NH4)(2)SO4, and H2SO4) and at three different concentrations (0.05, 0.25, and 2.0 M). Among all the prepared EEGOs, the most impressive performance was observed with the EEGO synthesized in 0.05 M H2SO4 (Pd@EEGOSA-0.05), which demonstrated an ethanol oxidation response of 106.5 mA cm(-2). This value significantly surpasses those of other synthesized materials for comparison, including Pd@VC (73.7 mA cm(-2)) and Pd@rGO (56.5 mA cm(-2)). SEM analyses indicated that EEGOs possess a flat layered structure, unlike the wrinkled rGO and hemispherical VC structures. FTIR analyses revealed fewer oxygen-containing functional groups in EEGOs compared to GO from Hummer's method. XPS analyzes revealed the presence of comparable functional groups distributed in varying proportions on the surfaces of the nanocomposites. EIS measurements indicated that Pd@EEGOSA-0.05 exhibited the minimum charge transfer resistance (Rct) among all the nanocomposites. ECSA (88.84 m(2) g(-1)) and ECSACO (35.04 m(2) g(-1)) values of Pd@EEGOSA-0.05 were much higher than that of Pd@VC and Pd@rGO. The results further demonstrated that the stability of Pd@EEGOSA-0.05 significantly exceeded that of both Pd@VC and Pd@rGO.