Comparison of O3 removal materials – Toyota's ferrihydrite represented by letter A
Researchers at Toyota Central Research and Development Labs in Japan claim to have developed a mesoporous two-line ferrihydrite (M2LFh) that, if used in an ozone (O3) filter, could remove up to 95 percent of unreacted O3. Ferrihydrite is a substance composed of iron, oxygen and water, as you most assuredly already knew, right?
The two-line (derived from its X-ray diffraction properties, which shows two lines) ferrihydrite material is porous, boasts a massive inner surface area and has a high percentage of iron sites at or near its surface. All of these qualities, according to the team of researchers, add up to make M2LFh an ideal material for O3 removal. A snippet from the team's report reads:
Yes, the sample graph shown above says M2LFh is the best at removing O3. However, it should be noted that Toyota's own research team drew up that graph....Among a wide range of materials tested at room temperature, we found M2LFh to be the most efficient candidate for O3 removal; it showed about 95 percent O3 removal with high reproducibility.
[Source: Wiley Online Library]