Exploring Pretreatment-Morphology Relationships: Ab Initio Wulff Construction for RuO2 Nanoparticles under Oxidising Conditions

We present a DFT‐based Wulff construction of the equilibrium shape of RuO2 particles in an oxygen environment. The obtained intricate variations in the crystal habit with the oxygen chemical potential allow for a detailed discussion of the dependence on the oxidising pretreatment used in recent powder catalyst studies. The analysis specifically indicates an incomplete particle shape equilibration in previously used low‐temperature calcination. Equilibrated particles could be active CO oxidation catalysts with long‐term stability in oxidising feed and then represent an interesting alternative to the previously suggested core–shell concept. Who's afraid of the Wulff? First‐principles Wulff shapes reveal an intricate dependence of the RuO2 crystal habit on the oxidizing pretreatment used in recent powder catalyst studies.