Heterostructuring Mesoporous 2D Iridium Nanosheets with Amorphous Nickel Boron Oxide Layers to Improve Electrolytic Water Splitting

Yunqing Kang; Bo Jiang; Victor Malgras; Yanna Guo; Ovidiu Cretu; Koji Kimoto; Aditya Ashok; Zhe Wan; Hexing Li; Yoshiyuki Sugahara; Yusuke Yamauchi; Toru Asahi

doi:10.1002/smtd.202100679

Heterostructuring Mesoporous 2D Iridium Nanosheets with Amorphous Nickel Boron Oxide Layers to Improve Electrolytic Water Splitting

Small Methods. 2021 Oct;5(10):e2100679. doi: 10.1002/smtd.202100679. Epub 2021 Sep 1.

Authors

Yunqing Kang^{1

2}, Bo Jiang³, Victor Malgras², Yanna Guo¹, Ovidiu Cretu⁴, Koji Kimoto⁴, Aditya Ashok⁵, Zhe Wan³, Hexing Li³, Yoshiyuki Sugahara^{1

6}, Yusuke Yamauchi^{2

5

6}, Toru Asahi^{1

6}

Affiliations

¹ Department of Nanoscience and Nanoengineering, Department of Life Science and Medical Bioscience and Department of Applied Chemistry, Faculty of Science and Engineering, Waseda University, Shinjuku, Tokyo, 169-8555, Japan.
² JST-ERATO Yamauchi Materials Space-Tectonics Project and International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki, 305-0044, Japan.
³ The Education Ministry Key Lab of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University, Shanghai, 200234, China.
⁴ Electron Microscopy Group, National Institute for Materials Science (NIMS), Tsukuba, Ibaraki, 305-0044, Japan.
⁵ Australian Institute for Bioengineering and Nanotechnology (AIBN) and School of Chemical Engineering, The University of Queensland, Brisbane, QLD, 4072, Australia.
⁶ JST-ERATO Yamauchi Materials Space-Tectonics Project, Kagami Memorial Research Institute for Materials Science and Technology, Waseda University, Shinjuku, Tokyo, 169-0051, Japan.

PMID: 34927951
DOI: 10.1002/smtd.202100679

Abstract

2D heterostructures exhibit a considerable potential in electrolytic water splitting due to their high specific surface areas, tunable electronic properties, and diverse hybrid compositions. However, the fabrication of well-defined 2D mesoporous amorphous-crystalline heterostructures with highly active heterointerfaces remains challenging. Herein, an efficient 2D heterostructure consisting of amorphous nickel boron oxide (Ni-B_i ) and crystalline mesoporous iridium (meso-Ir) is designed for water splitting, referred to as Ni-B_i /meso-Ir. Benefiting from well-defined 2D heterostructures and strong interfacial coupling, the resulting mesoporous dual-phase Ni-B_i /meso-Ir possesses abundant catalytically active heterointerfaces and boosts the exposure of active sites, compared to their crystalline and amorphous mono-counterparts. The electronic state of the iridium sites is tuned favorably by hybridizing with Ni-B_i layers. Consequently, the Ni-B_i /meso-Ir heterostructures show superior and stable electrochemical performance toward both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in an alkaline electrolyte.

Keywords: 2D materials; amorphous-crystalline interfaces; electrochemical water splitting; heterostructures; mesoporous materials.

Abstract

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