3DOM CeO2–Al2O3 with ordered mesopore walls is fabricated via the PMMA-templating route.
3DOM 26.9CeO2–Al2O3 displays a bimodal macro/mesoporous architecture.
3DOM 26.9CeO2–Al2O3 supported noble metal is prepared via the polymer-protective reduction.
0.27Pt/3DOM 26.9CeO2–Al2O3 performs the best in toluene oxidation.
Oads content, reducibility, and noble metal—support interaction govern the catalytic activity.