V-Integration Modulates t2g -Electrons of a Single Crystal Ir1- x (Ir0.8 V0.2 O2 )x -BHC for Boosted and Durable OER in Acidic Electrolyte

Waqar Ahmad; Yunpeng Hou; Rashid Khan; Liguang Wang; Shiyu Zhou; Kun Wang; Zhengwei Wan; Shaodong Zhou; Wenjun Yan; Min Ling; Chengdu Liang

doi:10.1002/smtd.202201247

V-Integration Modulates t_2g -Electrons of a Single Crystal Ir_1- _x (Ir_0.8 V_0.2 O₂ )_x -BHC for Boosted and Durable OER in Acidic Electrolyte

Small Methods. 2023 Jul;7(7):e2201247. doi: 10.1002/smtd.202201247. Epub 2023 Apr 22.

Authors

Waqar Ahmad^{1

2}, Yunpeng Hou^{1

2}, Rashid Khan^{1

2}, Liguang Wang^{1

2}, Shiyu Zhou^{1

2}, Kun Wang^{1

2}, Zhengwei Wan^{1

2}, Shaodong Zhou^{1

2}, Wenjun Yan^{3

1}, Min Ling^{1

2}, Chengdu Liang^{1

2}

Affiliations

¹ College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310058, China.
² Institute of Zhejiang University-Quzhou, 78 Jinhua Boulevard, Quzhou, 324000, China.
³ School of Automation, Hangzhou Dianzi University, Hangzhou, 310018, China.

PMID: 37086116
DOI: 10.1002/smtd.202201247

Abstract

Realizing efficacious π-donation from the O 2p orbital to electron-deficient metal (t_2g ) d-orbitals along with separately tuned adsorption of *O and *OOH, is an imperious pre-requisite for an electrocatalyst design to demonstrate boosted oxygen evolution reaction (OER) performance. To regulate the π-donation and the adsorption ability for *O and *OOH, herein, a facile strategy to modulate the electron transfer from electron-rich t_2g -orbitals to electron-deficient t_2g -orbitals, via strong π-donation from the π-symmetry lone pairs of the bridging O^2- , and the d-band center of a biomimetic honeycomb (BHC)-like nanoarchitecture (Ir_1- _x (Ir_0.8 V_0.2 O₂ )_x -BHC) is introduced. The suitable integration of V heteroatoms in the single crystal system of IrO₂ decreases the electron density on the neighboring Ir sites, and causes an upshift in the d-band center of Ir_1- _x (Ir_0.8 V_0.2 O₂ )_x -BHC, weakening the adsorption of *O while strengthening that of *OOH, lowers the energy barrier for OER. Therefore, BHC design demonstrates excellent OER performance (shows a small overpotential of 238 mV at 10 mA cm^-2 and a Tafel slope of 39.87 mV dec^-1 ) with remarkable stability (130 h) in corrosive acidic electrolyte. This work opens a new corridor to design robust biomimetic nanoarchitectures of modulated π-symmetry (t_2g ) d-orbitals and the band structure, to achieve excellent activity and durability in acidic environment.

Keywords: biomimetics; d-band centers; nanoarchitectures; nanoclusters; t2g-orbitals; π-donation.

Abstract

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