Exsolution Modeling and Control to Improve the Catalytic Activity of Nanostructured Electrodes

In situ exsolution for nanoscale electrode design has attracted considerable attention because of its promising activity and high stability. However, fundamental research on the mechanisms underlying particle growth remains insufficient. Herein, cation-diffusion-determined exsolution is presented using an analytical model based on classical nucleation and diffusion. In the designed perovskite system, the exsolution trend for particle growth is consistent with this diffusion model, which strongly depends on the initial cation concentration and reduction conditions. Based on the experimental and theoretical results, a highly Ni-doped anode and an electrochemical switching technique are employed to promote exsolution and overcome growth limitations. The optimal cell exhibits an outstanding maximum power density of 1.7 W cm(-2) at 900 degrees C and shows no evident degradation when operating at 800 degrees C for 240 h under wet H-2. This study provides crucial insights into the developing and tuning of heterogeneous catalysts for energy-conversion applications.

Automated summary

This study reveals that in the perovskite system, the nucleation and diffusion of nanoscale electrodes are determined by cation diffusion, with the initial cation concentration and reduction conditions playing critical roles. By employing a highly Ni-doped anode and an electrochemical switching technique, the performance limitations of electrode growth are overcome, resulting in outstanding performance. This research provides crucial insights into the development and tuning of heterogeneous catalysts for energy conversion applications.