Building Electron/Proton Nanohighways for Full Utilization of Water Splitting Catalysts

Gaoqiang Yang, Shule Yu, Zhenye Kang, Yifan Li, Guido Bender, Bryan Pivovar, Johney Green Jr., David Cullen, Feng-Yuan Zhang

Research output: Contribution to journalArticlepeer-review

54 Scopus Citations

Abstract

Low electron/proton conductivities of electrochemical catalysts, especially earth-abundant nonprecious metal catalysts, severely limit their ability to satisfy the triple-phase boundary (TPB) theory, resulting in extremely low catalyst utilization and insufficient efficiency in energy devices. Here, an innovative electrode design strategy is proposed to build electron/proton transport nanohighways to ensure that the whole electrode meets the TPB, therefore significantly promoting enhance oxygen evolution reactions and catalyst utilizations. It is discovered that easily accessible/tunable mesoporous Au nanolayers (AuNLs) not only increase the electrode conductivity by more than 4000 times but also enable the proton transport through straight mesopores within the Debye length. The catalyst layer design with AuNLs and ultralow catalyst loading (≈0.1 mg cm−2) augments reaction sites from 1D to 2D, resulting in an 18-fold improvement in mass activities. Furthermore, using microscale visualization and unique coplanar-electrode electrolyzers, the relationship between the conductivity and the reaction site is revealed, allowing for the discovery of the conductivity-determining and Debye-length-determining regions for water splitting. These findings and strategies provide a novel electrode design (catalyst layer + functional sublayer + ion exchange membrane) with a sufficient electron/proton transport path for high-efficiency electrochemical energy conversion devices.

Original languageAmerican English
Article number1903871
Number of pages10
JournalAdvanced Energy Materials
Volume10
Issue number16
DOIs
StatePublished - 2020

Bibliographical note

Publisher Copyright:
© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

NREL Publication Number

  • NREL/JA-5900-77326

Keywords

  • coplanar electrodes
  • electrochemical catalysts
  • electron/proton conductivity
  • nanolayers
  • oxygen evolution reaction
  • straight mesopores
  • water splitting

Fingerprint

Dive into the research topics of 'Building Electron/Proton Nanohighways for Full Utilization of Water Splitting Catalysts'. Together they form a unique fingerprint.

Cite this