Aluminum oxide is not magnetic, but the iron oxide (presumably bonded to the other ingredients) is magnetic.
> discrete nanoflakes of (Al2O3@v-MoS2)/Cu/Fe3O4
https://www.nature.com/articles/s44221-023-00079-4
> discrete nanoflakes of (Al2O3@v-MoS2)/Cu/Fe3O4
https://www.nature.com/articles/s44221-023-00079-4