Figure 1

Bight-field transmission electron micrographs recorded in TEM mode. (A) Of leached Au/Fe₂O₃ (hematite) catalyst at room temperature, showing voids and Au nanoparticles; (B) same support particle imaged at 500°C, revealing Au particle growth and void shrinkage; (C) diffractogram from heated particle, consistent with a <112 > zone axis of magnetite (Fe₃O₄). The dim, fine spots in diffractogram were from that of hematite.