TY - JOUR
T1 - Anti-Ferromagnetic RuO2
T2 - A Stable and Robust OER Catalyst over a Large Range of Surface Terminations
AU - Liang, Qiuhua
AU - Bieberle-Hütter, Anja
AU - Brocks, Geert
N1 - Funding Information:
Q.L. acknowledges funding from the China Scholarship Council (CSC) (No. 201708450082). A.B.-H. acknowledges the financial support from M-ERA.NET (project “MuMo4PEC” no. 4089). This work was carried out on the Dutch national e-infrastructure with the support of SURF Cooperative. Michael Verhage and Dr. Kees Flipse, Technical University Eindhoven, The Netherlands, as well as Dr. Gilles de Wijs, Radboud University, are thanked for fruitful discussions. A preliminary version of the present work can be found in Q.L.’s thesis.
Publisher Copyright:
©
PY - 2022/1/27
Y1 - 2022/1/27
N2 - Rutile RuO2 is a prime catalyst for the oxygen evolution reaction (OER) in water splitting. Whereas RuO2 is typically considered to be non-magnetic (NM), it has recently been established as being anti-ferromagnetic (AFM) at room temperature. The presence of magnetic moments on the Ru atoms signals an electronic configuration that is markedly different from what is commonly assumed, the effect of which on the OER is unknown. We use density functional theory (DFT) calculations within the DFT+U approach to model the OER process on NM and AFM RuO2(110) surfaces. In addition, we model the thermodynamic stability of possible O versus OH terminations of the RuO2(110) surface and their effect on the free energies of the OER steps. We find that the AFM RuO2(110) surface gives a consistently low overpotential in the range 0.4-0.5 V, irrespective of the O versus OH coverage, with the exception of a 100% OH-covered surface, which is, however, unlikely to be present under typical OER conditions. In contrast, the NM RuO2(110) surface gives a significantly higher overpotential of ∼0.7 V for mixed O/OH terminations. We conclude that the magnetic moment of RuO2 supplies an important contribution to obtaining a low overpotential and to its insensitivity to the exact O versus OH coverage of the (110) surface.
AB - Rutile RuO2 is a prime catalyst for the oxygen evolution reaction (OER) in water splitting. Whereas RuO2 is typically considered to be non-magnetic (NM), it has recently been established as being anti-ferromagnetic (AFM) at room temperature. The presence of magnetic moments on the Ru atoms signals an electronic configuration that is markedly different from what is commonly assumed, the effect of which on the OER is unknown. We use density functional theory (DFT) calculations within the DFT+U approach to model the OER process on NM and AFM RuO2(110) surfaces. In addition, we model the thermodynamic stability of possible O versus OH terminations of the RuO2(110) surface and their effect on the free energies of the OER steps. We find that the AFM RuO2(110) surface gives a consistently low overpotential in the range 0.4-0.5 V, irrespective of the O versus OH coverage, with the exception of a 100% OH-covered surface, which is, however, unlikely to be present under typical OER conditions. In contrast, the NM RuO2(110) surface gives a significantly higher overpotential of ∼0.7 V for mixed O/OH terminations. We conclude that the magnetic moment of RuO2 supplies an important contribution to obtaining a low overpotential and to its insensitivity to the exact O versus OH coverage of the (110) surface.
KW - UT-Hybrid-D
UR - http://www.scopus.com/inward/record.url?scp=85123361178&partnerID=8YFLogxK
U2 - 10.1021/acs.jpcc.1c08700
DO - 10.1021/acs.jpcc.1c08700
M3 - Article
AN - SCOPUS:85123361178
SN - 1932-7447
VL - 126
SP - 1337
EP - 1345
JO - The Journal of physical chemistry C
JF - The Journal of physical chemistry C
IS - 3
ER -