Fluorine Engineered Self‐Supported Ultrathin 2D Nickel Hydroxide Nanosheets as Highly Robust and Stable Bifunctional Electrocatalysts for Oxygen Evolution and Urea Oxidation Reactions. Issue 7 (10th December 2021)

• Record Type: Journal Article
• Authors: Patil, Swati J.; Chodankar, Nilesh R.; Hwang, Seung‐Kyu; Rama Raju, Ganji Seeta; Huh, Yun‐Suk; Han, Young‐Kyu
• Is Part Of: Small. Volume 18:Issue 7(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-12-10
• Subjects: 2D nanostructures -- doping -- heteroatoms -- overall water splitting -- urea electrolysis; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202103326
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: Developing highly efficient noble‐metal‐free electrocatalysts with a scalable and environmentally friendly synthesis approach remains a challenge in the field of electrocatalytic water splitting. To overcome this problem, self‐supported fluorine‐modified 2D ultrathin nickel hydroxide (F‐Ni(OH)2 ) nanosheets (NSs) for the oxygen evolution reaction (OER) and urea oxidation reaction (UOR) are prepared with a scalable and ascendant one‐step synthesis route. The enhanced redox activity, electrical conductivity and a great number of exposed active sites of the heterogeneous catalysts improve charge migration for the electrocatalytic reactions. The density of states of the d orbitals of the Ni atoms significantly increases near the Fermi level, thereby indicating that the Ni atoms near the F‐dopants promote electrical conduction in the Ni(OH)2 monolayer. The F‐Ni(OH)2 electrocatalyst exhibits notable OER and UOR activity with onset potentials of 1.43 and 1.16 V versus RHE, respectively required to reach 10 mA cm −2, which are comparable to those of commercial noble‐metal‐based electrocatalysts. With RuCo‐OH nanospheres, the settled F‐Ni(OH)2 ||RuCo‐OH cell requires merely 1.55 and 1.37 V to reach 10 mA cm −2 with superb durability for 24 h in overall water and urea electrolysis, respectively. Overall, high‐quality, and efficient noble‐metal‐free electrocatalysts for overall water and urea electrolysis can be prepared with a simple, scalable, and reproducible preparation method. Abstract : The use of self‐supported fluorine‐doped Ni(OH)2 and RuCo‐OH electrocatalysts as anode and cathode results in excellent electrocatalytic performance in terms of low overpotential for water and urea electrolysis with long term durability in alkaline electrolyte.