Modulating the Electronic Structure of RuO2 through Cr Solubilizing for Improved Oxygen Evolution Reaction. Issue 9 (25th July 2022)

• Record Type: Journal Article
• Authors: Chen, Haixin; Zhang, Xiaofeng; Geng, Shipeng; Song, Shuqin; Wang, Yi
• Is Part Of: Small methods. Volume 6:Issue 9(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-07-25
• Subjects: acidic media -- Cr -- density functional theory -- oxygen evolution reaction -- RuO 2; Nanotechnology -- Methodology -- Periodicals; Nanotechnology -- Periodicals; Periodicals; 620.5028
• DOI: 10.1002/smtd.202200636
• Languages: English
• ISSNs: 2366-9608

Abstract

Abstract: Hydrogen production from water electrolysis is important for the sustainable development of hydrogen energy. Nevertheless, the naturally torpid property of anodic oxygen evolution reaction (OER) kinetics and poor stability of its catalysts significantly restrict the development of electrochemical water splitting. Here, a Ru0.6 Cr0.4 O2 electrocatalyst is synthesized, which reveals excellent OER activity with the overpotential of only 195 mV at 10 mA cm −2 and excellent stability with the potential increase of merely 5.3 mV after 20 h continuous OER test in acidic media. Theoretical calculations reveal that the solubilizing of Cr into RuO2 could adjust the electron distribution, making the d‐band center of Ru far away from the Fermi level. This behavior reduces the binding energy with Ru and O and accelerates the rate‐determining step of OER (i.e., the formation of *OOH), thereby increasing OER activity. In addition, the incorporation of Cr increases the energy of oxygen defect formation and reduces the participation of lattice oxygen, thus improving the stability of the catalyst. This research furnishes a feasible policy for the development of highly active and stable catalysts in acidic media by regulating the electronic structure of RuO2 . Abstract : The Cr incorporation changes the electron distribution of RuO2 which decreases the d‐band center of Ru and the energy barrier of *OOH adsorbed on RuO2 (1 1 0), thus being favorable to the activity of oxygen evolution reaction in acidic electrolyte. Additionally, the oxidation resistance of Ru is significantly reinforced by inhibiting the lattice O oxidation mechanism pathway, resulting in enhanced stability.