Boosting Water Dissociation Kinetics on Pt–Ni Nanowires by N‐Induced Orbital Tuning. Issue 16 (27th February 2019)

• Record Type: Journal Article
• Authors: Xie, Yufang; Cai, Jinyan; Wu, Yishang; Zang, Yipeng; Zheng, Xusheng; Ye, Jian; Cui, Peixin; Niu, Shuwen; Liu, Yun; Zhu, Junfa; Liu, Xiaojing; Wang, Gongming; Qian, Yitai
• Is Part Of: Advanced materials. Volume 31:Issue 16(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-02-27
• Subjects: electrocatalysts -- hydrogen evolution reaction -- orbital tuning -- Pt–Ni nanowires -- water dissociation kinetics; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201807780
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Although it is commonly believed that the water‐dissociation‐related Volmer process is the rate‐limiting step for alkaline hydrogen evolution reaction (HER) on Pt‐based catalysts, the underlying essence, particularly on the atomic scale, still remains unclear. Herein, it is revealed that the sluggish water‐dissociation behavior probably stems from unfavorable orbital orientation and the kinetic issue is successfully resolved via N‐induced orbital tuning. Impressively, N modified Pt–Ni nanowires deliver an ultralow overpotential of 13 mV at 10 mA cm −2, which represents a new benchmark for alkaline HER catalysis. Fine‐structural characterization and density functional theory analysis illustrate that the introduced nitrogen can uniquely modulate the electron densities around the Ni sites, and further create empty d z 2 orbitals with superior orientation for water adsorption and activation. More importantly, it is demonstrated that N‐induced orbital modulation can generally boost the alkaline HER activities of Pt–Co, Pt–Ni, and Pt–Cu, offering a new perspective for the design of HER catalysts and beyond. Abstract : The water dissociation kinetics of Pt–Ni nanowires are significantly boosted via N‐induced orbital tuning. N can specifically bind to the Ni sites and subsequently enable the Ni sites to provide empty d z 2 orbitals for water adsorption and activation. These N‐modified Pt–Ni nanowires display an unprecedented alkaline hydrogen evolution catalysis.