[Kevmo]

a form of iron called hematite, a low band gap semiconductor material,
***I didn’t know Iron was considered a semiconductor. I suppose you could consider Carbon a high bandgap semiconductor, so Iron by that definition would be a low bandgap semi...

[RippinGood]

for what it’s worth - the headline was not the only thing misleading / wrong.

hematite is iron oxide (Fe2O3). Rust is primarily hydrated hematite (Fe2O3 with some water molecules attached)

It would have been more accurate to say that the titania (TiO2) and rust were combined...

Iron is a metallic conductor; carbon as diamond is indeed a wide bandgap semiconductor (or insulator), although graphite is a conductor. There are differences between a low bandgap semiconductor and a metal in terms of the electrical properties as a function of temperature, etc.

Interesting work, actually - too bad the writer of the article mucked it up...