Publication detail

Anodic TiO2 nanotube layers decorated by Pd nanoparticles using ALD: An efficient electrocatalyst for methanol oxidation

BAWAB, B. THALLURI, S. RODRIGUEZ PEREIRA, J. SOPHA, H. ZAZPE, R. MACÁK, J.

Original Title

Anodic TiO2 nanotube layers decorated by Pd nanoparticles using ALD: An efficient electrocatalyst for methanol oxidation

Type

journal article in Web of Science

Language

English

Original Abstract

Herein, we report the performance of Pd nanoparticles (NPs) prepared by Atomic Layer Deposition (ALD) as a catalyst for methanol electro-oxidation. Pd NPs were decorated onto anodic TiO2 nanotube (TNT) layers as supporting material that possess a large available surface area and direct electrical contact via the underlying titanium foil. Different Pd loadings (150 - 300 - 450 - 600 ALD cycles) show different particles sizes ranging between 7 and 12 nm, as revealed by transmission electron microscopy. Coalescence dominated visibly from 450 ALD cycles, which led to a porous Pd layer all along the TNT walls rather than the growth of individual particles. Electrocatalytic performance was investigated by cyclic voltammetry (CV), where the catalytic activity increased proportional with Pd loading up to the highest values for 400 and 450 cycles, whereas a further increase in the number of ALD cycles (N-ALD) did not show any additional improvement in methanol oxidation current densities. TNT layers decorated with 400, 450 and 600 Pd ALD cycles show featureless curves suggesting complete anti-poisoning ability or possibly a proof of a direct conversion from CH3OH to CO2 (without any intermediate byproducts). The lack of an oxidation peak during the anodic scan and therefore a reduction peak during the cathodic scan, confirms Pd NPs (stabilized by TiO2) efficiently utilize OHads and chemisorbed CH3OH in a way that its CO poisoning was inhibited. As a result, the tuned high surface area TNT layers exhibited excellent performance as a supporting material for Pd NPs against formation of electrochemical poisoning species. Finally, the mechanism of the TNT layers interaction with Pd NPs, which led to the propelling methanol oxidation reaction without loss in performance over cycling is postulated.

Keywords

TiO2 nanotube layers; Pd nanoparticles; Atomic Layer Deposition; Electrocatalysis; Methanol electro-oxidation

Authors

BAWAB, B.; THALLURI, S.; RODRIGUEZ PEREIRA, J.; SOPHA, H.; ZAZPE, R.; MACÁK, J.

Released

10. 10. 2022

Publisher

Elsevier

Location

OXFORD

ISBN

1873-3859

Periodical

ELECTROCHIMICA ACTA

Year of study

429

Number

1

State

United Kingdom of Great Britain and Northern Ireland

Pages from

1

Pages to

11

Pages count

11

URL

https://www.sciencedirect.com/science/article/pii/S0013468622012014

Full text in the Digital Library

http://hdl.handle.net/11012/208675

BibTex

@article{BUT179176,
  author="Bilal {Bawab} and Sitaramanjaneya Mouli {Thalluri} and Jhonatan {Rodriguez Pereira} and Hanna Ingrid {Sopha} and Raúl {Zazpe Mendioroz} and Jan {Macák}",
  title="Anodic TiO2 nanotube layers decorated by Pd nanoparticles using ALD: An efficient electrocatalyst for methanol oxidation",
  journal="ELECTROCHIMICA ACTA",
  year="2022",
  volume="429",
  number="1",
  pages="11",
  doi="10.1016/j.electacta.2022.141044",
  issn="1873-3859",
  url="https://www.sciencedirect.com/science/article/pii/S0013468622012014"
}