Dopant Evolution in Electrocatalysts after Hydrogen Oxidation Reaction in an Alkaline Environment
Su‐Hyun Yoo, Leonardo Shoji Aota, Sangyong Shin, Ayman A. El‐Zoka, Phil Woong Kang, Yonghyuk Lee, Hyunjoo Lee, Se‐Ho Kim, Baptiste Gault
Abstract
High Resolution Image Download MS PowerPoint Slide Introduction of interstitial dopants has opened a new pathway to optimize nanoparticle catalytic activity for, e.g., hydrogen evolution/oxidation and other reactions. Here, we discuss the stability of a property-enhancing dopant, B, introduced through the controlled synthesis of an electrocatalyst Pd aerogel. We observe significant removal of B after the hydrogen oxidation reaction. Ab initio calculations show that the high stability of subsurface B in Pd is substantially reduced when H is adsorbed/absorbed on the surface, favoring its departure from the host nanostructure. The destabilization of subsurface B is more pronounced, as more H occupies surface sites and empty interstitial sites. We hence demonstrate that the H 2 fuel itself favors the microstructural degradation of the electrocatalyst and an associated drop in activity.