Cu Doped Crystalline Carbon-Conjugated g-C3N4, a Promising Oxygen Reduction Catalyst by Theoretical Study. Issue 12 (16th July 2019)

• Record Type: Journal Article
• Authors: Yang, Yuewen; Yin, Cong; Li, Kai; Tang, Hao; Wang, Ying; Wu, Zhijian
• Is Part Of: Journal of the Electrochemical Society. Volume 166:Issue 12(2019)
• Page Start: F755
• Page End: F759
• Publication Date: 2019-07-16
• Subjects: Electrocatalysis -- oxygen reduction reaction -- reaction mechanism; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/2.0731912jes
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : The single atom supported by carbon nitride (g-C3 N4 ) materials, as efficient substitutes for platinum catalysts, recently have attracted extensive attention. Owing to poor electron mobility, g-C3 N4 suffers from unavoidable energy loss, while g-C3 N4 with crystalline carbons (g-C3 N4 /C) can enhance electron transfer. In this study, single Cu atom doped g-C3 N4 (Cu/g-C3 N4 ) and g-C3 N4 /C (Cu/g-C3 N4 /C) are investigated by using the density functional method. Our study indicated that they are stable thermodynamically. ORR intermediates have weakened adsorption energies in Cu/g-C3 N4 /C compared with Cu/g-C3 N4 . For Cu/g-C3 N4, the rate-determining step is O2 hydrogenation to form OOH with an energy barrier of 0.40 eV, similar to 0.39 eV for Pd/g-C3 N4 . Compared with Cu/g-C3 N4, Cu/g-C3 N4 /C shows higher catalytic activity. For Cu/g-C3 N4 /C, the energy barrier at the rate-determining step is 0.15 eV, smaller than 0.40 eV for Cu/g-C3 N4, and much smaller than 0.80 eV for Pt (111). Meanwhile, the predicted working potential is 0.57 V for Cu/g-C3 N4 /C, also larger than 0.22 V for Cu/g-C3 N4 . Thus, the introduced crystalline carbons on Cu/C3 N4 /C enhances not only electron conduction but also catalytic activity.