Challenges in applying highly active Pt-based nanostructured catalysts for oxygen reduction reactions to fuel cell vehicles

Kodama, Kensaku; Nagai, T.; Kuwaki, Akira; Jinnouchi, Ryosuke; Morimoto, Yu

doi:10.1038/s41565-020-00824-w

“…As discussed in the introduction, the RDE technique is known for its simplicity and is widely used for fundamental research. The liquid electrolyte environment and low reactant mass transport however limit the extrapolation of the results to real devices [50]. The BOT ORR activity data are presented in Figure 3a, the respective Tafel plots (estimation) are shown in Figure S8 demonstrating that the Tafel slopes are basically consistent with the ones obtained in the RDE measurement.…”

Section: Figuresupporting

confidence: 68%

Elucidating Pt-Based Nanocomposite Catalysts for the Oxygen Reduction Reaction in Rotating Disk Electrode and Gas Diffusion Electrode Measurements

Du¹,

Quinson²,

Zana³

et al. 2021

Preprint

0

View full text Add to dashboard Cite

In the present study we compare different nanoparticle (NP) composites (nanocomposites) as potential electrocatalysts for the oxygen reduction reaction (ORR). The nanocomposites consist of a mixture of Pt and Ir NPs and Pt and Au NPs, respectively, that are immobilized onto a high surface area carbon support. Pt NPs supported on the same carbon support serve as benchmark. The performance testing was performed in a conventional rotating disk electrode (RDE) setup as well as in a recently introduced gas diffusion electrode (GDE) setup providing high mass transport conditions. The ORR activity is determined, and the degradation tested using accelerated degradation tests (ADTs). It is shown that with respect to the benchmark, the Pt – Au nanocomposite concept exhibits improved ORR activity as well as improved stability both in the RDE and the GDE measurements. By comparison, the Pt – Ir nanocomposite exhibits improved stability but lower ORR activity. Combining the GDE approach with small angle X-ray scattering, it is shown that the improved stability of the Pt – Au nanocomposite can be assigned to a reduced Pt particle growth due to the adjacent Au NPs. The results demonstrate that nanocomposites could be an alternative catalyst design strategy complementing the state-of-the-art alloying concepts.<br>

show abstract

“…As discussed in the introduction, the RDE technique is known for its simplicity and is widely used for fundamental research. The liquid electrolyte environment and low reactant mass transport however limit the extrapolation of the results to real devices 54 The BOT ORR activity data are presented in Figure 3a, the respective Tafel plots (estimation) are shown in Figure S8 demonstrating that the Tafel slopes are basically consistent with the ones obtained in the RDE measurement. From the GDE data it is apparent that in agreement with the RDE data and as compared to the Pt/C benchmark, the Pt-IrO2/C nanocomposite exhibits indeed a substantially inhibited ORR performance over a wide range of current densities up to 1500 mA cm -2 Geo.…”

Section: Figuresupporting

confidence: 67%

Elucidating Pt-Based Nanocomposite Catalysts for the Oxygen Reduction Reaction in Rotating Disk Electrode and Gas Diffusion Electrode Measurements

Du

¹

,

Quinson

²

,

Zana

³

et al. 2021

Preprint

1

0

View full text Add to dashboard Cite

In the present study we compare different nanoparticle (NP) composites (nanocomposites) as potential electrocatalysts for the oxygen reduction reaction (ORR). The nanocomposites consist of a mixture of Pt and Ir NPs and Pt and Au NPs, respectively, that are immobilized onto a high surface area carbon support. Pt NPs supported on the same carbon support serve as benchmark. The performance testing was performed in a conventional rotating disk electrode (RDE) setup as well as in a recently introduced gas diffusion electrode (GDE) setup providing high mass transport conditions. The ORR activity is determined, and the degradation tested using accelerated degradation tests (ADTs). It is shown that with respect to the benchmark, the Pt – Au nanocomposite concept exhibits improved ORR activity as well as improved stability both in the RDE and the GDE measurements. By comparison, the Pt – Ir nanocomposite exhibits improved stability but lower ORR activity. Combining the GDE approach with small angle X-ray scattering, it is shown that the improved stability of the Pt – Au nanocomposite can be assigned to a reduced Pt particle growth due to the adjacent Au NPs. The results demonstrate that nanocomposites could be an alternative catalyst design strategy complementing the state-of-the-art alloying concepts.<br>

show abstract

“…Proton exchange membrane fuel cells (PEMFCs) have attracted extensive attention due to their clean and sustainable energy conversion. [1][2][3][4] By now, Pt is the most active monometallic catalyst in PEMFCs. [5][6] Nevertheless, the sluggish kinetics of oxygen reduction reaction (ORR) at the cathode and the poor stability of electrocatalysts restrain the commercial development of PEMFCs.…”

Section: Introductionmentioning

confidence: 99%

Improved Stability of Octahedral PtCu by Rh Doping for the Oxygen Reduction Reaction

Wang

¹

,

Chen

²

,

Li

³

et al. 2021

View full text Add to dashboard Cite

Octahedral PtÀ M nanocrystals are recognized to be ideal catalysts for the oxygen reduction reaction (ORR) because of their outstanding electrocatalytic activity. However, these highactivity catalysts usually show shortage in the long-term stability since the octahedral morphology is severely destroyed and transition metals are easily leached out during the electrochemical test. Herein, we prepared octahedral PtCu and PtCuRh 0.05 nanocrystals with an edge length of about 15 nm. After being dispersed on carbon black, the octahedral PtCu/C catalyst exhibits a very high ORR activity with a specific activity and mass activity of 3.29 mA cm À 2 and 1.12 A mg Pt À 1 at 0.90 V, making it among one of the most active PtCu catalyst for ORR ever reported. Although the incorporation of Rh slightly decreases the ORR activity, it can improve the stability, and the half-wave potential is only shifted negatively by 1 mV after an accelerated durability test of 10,000 potential cycles for the PtCuRh 0.05 /C catalyst. The improved stability is attributed to the anchoring effect of the Rh atoms, which inhibits the leaching of Cu and helps to maintain the octahedral morphology during the ORR.

show abstract

Challenges in applying highly active Pt-based nanostructured catalysts for oxygen reduction reactions to fuel cell vehicles

Cited by 537 publications

References 104 publications

Elucidating Pt-Based Nanocomposite Catalysts for the Oxygen Reduction Reaction in Rotating Disk Electrode and Gas Diffusion Electrode Measurements

Elucidating Pt-Based Nanocomposite Catalysts for the Oxygen Reduction Reaction in Rotating Disk Electrode and Gas Diffusion Electrode Measurements

Elucidating Pt-Based Nanocomposite Catalysts for the Oxygen Reduction Reaction in Rotating Disk Electrode and Gas Diffusion Electrode Measurements

Improved Stability of Octahedral PtCu by Rh Doping for the Oxygen Reduction Reaction

Contact Info

Product

Resources

About