Synthesis of PtCo/ZSM-5/C electrocatalyst and electrochemical activity
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This study presents the synthesis and electrochemical characterization of a bimetallic PtCo electrocatalyst supported in a ZSM-5 zeolite and XC-72R Vulcan carbon 50 wt.% composite. Two synthesis methodologies were tested: reduction mediated by ethylene glycol and NaBH4. The catalyst electroactivity was assessed by measuring the electrochemical surface area, ESA, and the electrooxidation of methanol was evaluated by cyclic voltammetry and chronoamperometry in acid medium. The nanoelectrocatalysts were obtained with average particle size nearly 3.0 nm and ESA up to 44.7 m2 g−1, indicating the effectiveness of the synthesis methods and of the composite ZSM-5/C used as catalyst support. XPS studies showed that PtCo alloy was obtained by NaBH4 reduction. All samples presented good tolerance to carbonaceous species indicated by jf/jb ratio greater than 1 in methanol oxidation activity test. The 1-h chronoamperometry tests corroborated these results. Some samples obtained in the present work showed higher current density in steady state compared to the commercial sample used as reference and analyzed under the same experimental process. The results showed that the zeolite support was effective at improving catalytic activity independently of the alloy PtCo presence on the catalyst surface.
KeywordsCatalyst Zeolite Electrooxidation Methanol oxidation Electrocatalyst
The authors would like to thank Oleksii Kuznetsov for XRF measurements and CENABIO for TEM images.
This work was supported by the Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (Nos. E-26/110.665/2013 and E-26/010.001095/2015).
- 12.Yasumoto E, Hatoh K, Gamou T (1997) U.S. Patent No. 5,702,838Google Scholar
- 20.Bal L, Gao L, Conway BE (1993) Problem of in situ real area determination in evaluation of performance of rough or porous, gas-evolving electrocatalysts. Part 1—basis for distinction between capacitance of the double layer and pseudocapacitance due to absorbed H in the H2 evolution reaction at Pt. J Chem Soc 89:235–242Google Scholar
- 21.Bal L, Gao L, Conway BE (1993) Problem of in situ real-area determination in evaluation of performance of rough or porous, gas-evolving electrocatalysts. Part 2—unfolding of the electrochemically accessible surface of rough or porous electrodes: a case-study with an electrodeposited porous Pt electrode. J Chem Soc 89:243–249Google Scholar
- 35.Manohara R, Goodenough JB (2004) Methanol oxidation in acid on ordered NiTi. J Mater Chem 2:875–887Google Scholar