Wenping Tian, Changhao Wang, Yunsong Li, Xiaolin Hu
Oxygen electrochemistry, encompassing the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), is central to energy-related applications including zinc-air batteries (ZABs). However, the four-electron transfer process inherent to these reactions is significantly hindered by sluggish reaction kinetics. In this study, an efficient synergistic catalyst consisting of nitrogen-doped carbon nanotube composites (Au/Ru N-CNTs) modified by Au/Ru nanoparticles with dual catalytic sites was synthesized. Leveraging the significant enhancement of synergistic effect between catalytic activities using Au/Ru dual nanoparticles, has been demonstrated to be a key factor in achieving a power density of 246 mW cm −2 and exceptional stability of 636 h when employed as an air electrode in ZABs. Density functional theory (DFT) calculations show that the co-doping of Au and Ru substantially enhances the electronic structure near the Fermi energy level. These findings underscore the synergistic electronic and structural advantages of the Au/Ru N-CNTs system for catalytic applications, significantly boosting its performance in both ORR and OER. The synergistic integration of Au/Ru bimetallic nanoparticles on nitrogen-doped carbon nanotubes (Au/Ru N-CNTs) creates a highly efficient bifunctional electrocatalyst, where the complementary electronic effects between Au (electron donor) and Ru (electron acceptor) significantly enhance the catalytic activity of the N-CNT substrate. This cooperative interaction optimally modulates the electronic structure near the Fermi level, lowering the energy barriers for oxygen electrocatalysis by facilitating the formation and cleavage of critical intermediates (∗O and ∗OOH). The obtained catalyst demonstrates outstanding practical performance metrics, specifically achieving a peak power density of 246.77 mW cm −2 .