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Building Electron/Proton Nanohighways for Full Utilization of Water Splitting Catalysts
Author(s) -
Yang Gaoqiang,
Yu Shule,
Kang Zhenye,
Li Yifan,
Bender Guido,
Pivovar Bryan S.,
Green Johney B.,
Cullen David A.,
Zhang FengYuan
Publication year - 2020
Publication title -
advanced energy materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 10.08
H-Index - 220
eISSN - 1614-6840
pISSN - 1614-6832
DOI - 10.1002/aenm.201903871
Subject(s) - materials science , catalysis , conductivity , mesoporous material , electrochemical energy conversion , electrode , electrochemistry , proton transport , proton , chemical engineering , water splitting , anode , nanotechnology , inorganic chemistry , chemistry , photocatalysis , biochemistry , physics , quantum mechanics , engineering
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.