Fig. 14
a Schematic of Pt nanoparticle sintering showing how ceria can trap mobile Pt to suppress sintering. Cubes appear to be less effective than rods or polyhedral ceria. HAADF-STEM images of b 1 wt% Pt/CeO2-rod and c 1 wt% Pt/CeO2-polyhedra after aging at 800 °C for 10 h in flowing air. d Schematic of the formation Au single atoms on defective TiO2. e HAADF-STEM image of single atomic Au sites highlighted by red circles. f Elemental map**s showing the distribution of Ti (blue) and Au (red). a–c Adapted with permission from Ref. [158]. Copyright 2016, American Association for the Advancement of Science. d–f Adapted with permission from Ref. [166]. Copyright 2018, Wiley-VCH