Open AccessModulation of the Electronic Structure of IrSe 2 by Filling the Bi Atom as a Bifunctional Electrocatalyst for pH Universal Water Splitting
Author(s) -
Wang Xin,
Wang Dong,
Yin Wen-Jin,
Si Yubing,
Bu Kejun,
Wang Sishun,
Zhao Wei,
Huang Fuqiang
Publication year - 2021
Publication title -
advanced energy and sustainability research
Language(s) - English
Resource type - Journals
ISSN - 2699-9412
DOI - 10.1002/aesr.202000074
Subject(s) - bifunctional , electrocatalyst , oxygen evolution , water splitting , catalysis , chemistry , electrolyte , materials science , electronic structure , inorganic chemistry , nanotechnology , electrochemistry , electrode , computational chemistry , biochemistry , photocatalysis
Although IrSe 2 is a superior oxygen evolution catalyst, its electronic structure lacks active sites for hydrogen production and hinders its use as a bifunctional catalyst. The intercalation of Bi atoms into the IrSe 2 framework regulates its electronic structure with the improvement of performance. Herein, novel bismuth inserted iridium‐based selenide (BiIr 4 Se 8 ) is synthesized via solid‐state reaction. Interestingly, BiIr 4 Se 8 exhibits impressive activities with dual functionality in pH‐universal electrolytes. It achieves small overpotentials at 10 mA cm −2 toward hydrogen evolution (85 mV in acid and 252 mV in alkali) and oxygen evolution (379 mV in acid and 364 mV in alkali), which overmatches the benchmarking noble metal‐based electrocatalysts. When served as the bifunctional electrocatalyst to drive a water electrolyzer, BiIr 4 Se 8 affords 10 mA cm −2 at a voltage of 1.56 and 1.52 V RHE in 0.5 m H 2 SO 4 and 1 m KOH, far exceeding the Pt/C||RuO 2 and other published materials. Theoretical calculations show that a narrow bandgap is obtained due to the induced intermediate band derived from the combination of the p orbitals of Bi atoms and structure reconstruction, which promotes the electrocatalytical performance. This research introduces a new strategy to design channel structures and sheds light on their applications for water splitting.