Advances in Chemical Engineering and Science, 2020, 10, 99-112 https://www.scirp.org/journal/aces ISSN Online: 2160-0406 ISSN Print: 2160-0392 DOI: 10.4236/aces.2020.102007 Apr. 17, 2020 99 Advances in Chemical Engineering and Science Zirconia Modified Pd Electrocatalysts for DFAFCs Yuh-Jing Chiou 1* , Mao-Yuan Chen 1 , Yi-Lan Chang 1 , Hong-Ming Lin 2 , Andrzej Borodzinski 3 1 Department of Chemical Engineering and Biotechnology, Tatung University, Taiwan 2 Department of Material Science, Tatung University, Taiwan 3 Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland Abstract In order to enhance the Pd based anodic catalysts for direct formic acid fuel cells (DFAFCs), the research work includes increasing catalyst activity and preventing CO poison. In this study, various zirconium oxides-modified mul- ti-walled carbon nanotubes (MWCNTs) were prepared as the supports of Pd catalysts for DFAFCs by adjusting the preparation parameters: metal adding, sintering temperature and atmospheres. The prepared pure zirconia has both monoclinic and tetragonal phases. The addition of MWCNTs depresses the growth of monoclinic phase. A small amount of Pd adding allows both mo- noclinic and tetragonal zirconia structures to appear again. Pd nanoparticles of 20 wt% synthesized on MWCNTs and tetragonal ZrO 2 /MWCNTs have similar particle size, while Pd/[Pd:ZrO 2 /AO-MWCNTs-300Air-900Ar] have more nanoparticles aggregation. The electrochemical surface area can be im- proved by adding zirconia which implies those zirconia modified Pd catalysts better electrocatalytic performance. By analyzing the maximum current den- sity and the corresponding potential, Pd/AO-MWCNTs are inferred to un- dergo the formic acid direct oxidation initially. The Pd catalysts modified by tetragonal ZrO 2 have higher current density. Those having both tetragonal and monoclinic ZrO 2 modified Pd catalysts have lower potential of formic acid oxidation. All the Pd based catalysts with zirconia modification possess better CO resist ability and electrocatalytic activity. Pd/[ZrO 2 /AO-MWCNTs-300Air-900Ar] and Pd/[Pd:ZrO 2 /AO-MWCNTs-300Air-900Ar] which catalyze formic acid in direct oxidation path are the two best catalysts. Keywords DFAFCs, Dual Path, Zirconia, Pd, MWCNTs How to cite this paper: Chiou, Y.-J., Chen, M.-Y., Chang, Y.-L., Lin, H.-M. and Borodzinski, A. (2020) Zirconia Modified Pd Electrocatalysts for DFAFCs. Advances in Chemical Engineering and Science, 10, 99-112. https://doi.org/10.4236/aces.2020.102007 Received: February 17, 2020 Accepted: April 14, 2020 Published: April 17, 2020 Copyright © 2020 by author(s) and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access