Preparation of inverse opal cerium dioxide for optical properties research

•Inverse opal CeO2 was prepared and characterized.•The true filling factor of CeO2 is calculated and discussed.•Inverse opal CeO2 modulating light was investigated.

Inverse opal cerium dioxide (CeO2) is prepared with polystyrene (PS) microsphere opal template and sol–gel method, and characterized in detail. The opal template and inverse opal CeO2 show different colors in the light of halogen tungsten lamp and have a long-range ordered three dimensional periodic structure. Comparing with the opal template, the size of the inverse opal CeO2 shows shrinkage. The randomly selected positions of opal and inverse opal almost have the same peak position. The true filling factor of CeO2 is different from the theoretical value and calculated by testing the reflecting peak. The inverse opal CeO2 can modulate light by changing the diameter of air sphere and have directional stop band gap in the visible spectrum, which is expected to be some advanced and promising applications.