Improving the Performance of Palladium in Electrocatalysts

In a recent study published in the journal ACS Applied Energy Materials, researchers analyzed a palladium (Pd) composite-based electrocatalyst as an alternative to platinum (Pt) electrocatalyst-based anodes for application in methanol-based fuel cells.

Study: Lamellar and Conductive Ion Associations Advance the Electrochemical Catalytic Performance of Palladium. Image Credit: Maxx-Studio/

The fabricated Pd composite-based anode containing a Pd to molybdenum (Mo) atomic ratio of 1.8:1 demonstrated excellent catalytic performance for methanol oxidation reaction (MOR) with a high peak current density of 2178 mA·mg-1metal owing to high ion loading efficiency, good conductivity, rapid mass transferring in the lamellar structure, and the formation of abundant strain defects.

Additionally, high current density and mass activity retention after several cycles make it a promising electrochemical catalyst for the loading of various noble metals for the anode.

Electrocatalyst for Direct Methanol Fuel Cells

Hydrogen has safety issues during transportation and storage, which can be alleviated by converting it into other chemical compounds, such as methanol, ammonia, methane, and ethylene glycol, and converting it back to its original form inside a sophisticated fuel cell.

Direct methanol fuel cells (DMFCs) are a new generation of portable fuel cells in which methanol is directly converted into hydrogen before being used as fuel to generate electric current. The major issue with DMFCs is that the MOR has very slow kinetics on the anode.

The Pt- rubidium (Ru) alloy is the most commonly used catalyst for anodes that perform MOR. However, Pt has a limited reserve, and it is expensive, which hinders its application in DMFCs. Alternatively, non-Pt catalysts such as Pd composite-based electrocatalyst, nickel-based electrocatalyst, and copper-based electrocatalysts, which are more abundant on Earth, have shown excellent electrocatalytic performance.

About the Study

In this study, researchers synthesized a Pd composite-based electrocatalyst, designated as PdMoCTAB, by hydrothermally mixing Na2PdCl4, (NH4)6Mo7O24, and cetyltrimethylammonium bromide (CTAB).

The prepared composite had a conductive and lamellar ion association type colloid solution form. The Pd and Mo composition ratio of the electrolyte was varied by varying the amount of Na2PdCl4, (NH4)6Mo7O24 in the mixture.

Three compositions of Pd and Mo with atomic mass ratios of 1.8:1, 2.4:1, and 0.74:1were synthesized and denoted as Pd1.8Mo, Pd2.4Mo, and Pd0.74Mo. The presence of Pd contributed to the conductivity, whereas the electrostatic attraction of CTA+ towards [Mo7O24]6− and [PdBr4]2 resulted in the formation of an ion association with lamellar gaps.

Pd/PdMoCTAB sphere nanoparticles (denoted as Pd0.74Mo), Pd/PdMoCTAB nanosheets (denoted as Pd2.4Mo), and a mixture of (NH4)6Mo7O24 and CTAB (denoted as MoCTAB) were synthesized for the comparison.


Cyclic voltammetry (CV) results showed that the hydrogen adsorption charge of Pd1.8Mo, Pd2.4Mo, and Pd0.74Mo were 80.57, 44.40, and 37.09 m2g1, respectively. The mass activity of Pd1.8Mo of about 2178 mA mg1 was 2.6 times larger than that of Pd0.74Mo (829 mA mg1) and two times larger than that of Pd2.4Mo (1076 mA mg1).

The CO tolerance of catalysts, which was evident from the ratio of forward and backward current peaks (If/Ib), were 2.54, 2.08, and 1.7 for Pd1.8Mo, Pd2.4Mo, and Pd0.74Mo, respectively.


In summary, in this study researchers synthesized Pd composite-based electrocatalysts, PdMoCTAB, to replace Pt-based electrocatalyst for MOR performing anode material of DMFC by mixing Na2PdCl4, (NH4)6Mo7O24, and CTAB. Three samples with varied Pd to Mo atomic mass ratios were denoted as Pd1.8Mo, Pd2.4Mo, and Pd0.74Mo.

The Pd1.8Mo sample inside a chubby and lamellar structure demonstrated the optimum electrocatalytic performance owing to the generation of strain defects, steps, and kinks. Other than high current density, Pd1.8Mo exhibited high current density and mass activity retention after several cycles, more active centers, accelerating mass transfer, and tolerance to CO poisoning. Hence, Pd1.8Mo is a suitable alternative to Pt-based electrocatalyst for MOR.


Shi, J., Li, M., Zheng, Y., Ying, Y., Guo, X., Wu, Y., Liu, X., Wen, Y., Yang, H., Lamellar and Conductive Ion Associations Advance the Electrochemical Catalytic Performance of Palladium. ACS Applied Energy Materials, 2022,

Disclaimer: The views expressed here are those of the author expressed in their private capacity and do not necessarily represent the views of Limited T/A AZoNetwork the owner and operator of this website. This disclaimer forms part of the Terms and conditions of use of this website.

Bismay Prakash Rout

Written by

Bismay Prakash Rout

Bismay is a technical writer based in Bhubaneshwar, India. His academic background is in Engineering and he has extensive experience in content writing, journal reviewing, mechanical designing. Bismay holds a Masters in Materials Engineering and BE in Mechanical Engineering and is passionate about science & technology and engineering. Outside of work, he enjoys online gaming and cooking.


Please use one of the following formats to cite this article in your essay, paper or report:

  • APA

    Prakash Rout, Bismay. (2022, January 24). Improving the Performance of Palladium in Electrocatalysts. AZoM. Retrieved on July 23, 2024 from

  • MLA

    Prakash Rout, Bismay. "Improving the Performance of Palladium in Electrocatalysts". AZoM. 23 July 2024. <>.

  • Chicago

    Prakash Rout, Bismay. "Improving the Performance of Palladium in Electrocatalysts". AZoM. (accessed July 23, 2024).

  • Harvard

    Prakash Rout, Bismay. 2022. Improving the Performance of Palladium in Electrocatalysts. AZoM, viewed 23 July 2024,

Tell Us What You Think

Do you have a review, update or anything you would like to add to this news story?

Leave your feedback
Your comment type

While we only use edited and approved content for Azthena answers, it may on occasions provide incorrect responses. Please confirm any data provided with the related suppliers or authors. We do not provide medical advice, if you search for medical information you must always consult a medical professional before acting on any information provided.

Your questions, but not your email details will be shared with OpenAI and retained for 30 days in accordance with their privacy principles.

Please do not ask questions that use sensitive or confidential information.

Read the full Terms & Conditions.