Ir-oxide mediated surface restructure and corresponding impacts on durability of bimetallic NiOx@Pd nanocatalysts in oxygen reduction reaction

Dinesh Bhalothia, Dai Ling Tsai, Sheng Po Wang, Che Yan, Ting Shan Chan, Kuan Wen Wang, Tsan Yao Chen, Po Chun Chen

Research output: Contribution to journalArticlepeer-review

5 Scopus citations

Abstract

With proper conjunctions between inter/intra-particle domains, the activity and durability of heterogeneous nanocatalysts (NCs) can be substantially improved by more than an order. In this study, tri-metallic NCs comprising an Ir-clusters decorated unconformable Pd-shell over amorphous NiOx core crystal underneath (namely NPI) are developed for oxygen reduction reaction (ORR) in alkaline medium (0.1 M KOH). Results for NPI NCs with different extents of Ir decoration (1 and 14 wt%) are compared for clarifying the configuration effects corresponding to ORR performance. For the optimum case with an Ir loading of ∼1.0 wt%, the mass activity (MA) is 2066.8 mAmg−1. This value is ∼31-folds increased as compared to that of commercial J.M.-Pt/C catalyst (20 wt% Pt) at 0.85 V vs RHE (67.1 mA mg−1). Moreover, as prepared NPI-0025 NC exhibits nearly 100% stability when operated up to 21 k accelerated degradation test (ADT) cycles. By cross-referencing results of physical structure inspections and electrochemical analysis, we reveal that such a high ORR performance could be attributed to the incorporation of Ir atoms in defect sites of Ni–Pd interfaces. These Ir atoms facilitate the O2 splitting by electronegativity differences to the adjacent sites, therefore, improves the ORR performance of NPI NCs.

Original languageEnglish
Article number156160
JournalJournal of Alloys and Compounds
Volume844
DOIs
StatePublished - 5 Dec 2020

Keywords

  • Heterogeneous
  • Ir-clusters
  • Nanocatalysts
  • Oxygen reduction reaction
  • Wet chemical reduction method

Fingerprint

Dive into the research topics of 'Ir-oxide mediated surface restructure and corresponding impacts on durability of bimetallic NiO<sub>x</sub>@Pd nanocatalysts in oxygen reduction reaction'. Together they form a unique fingerprint.

Cite this