Can we make any substance that will produce ions at low temprature

Can we make any substance that will produce ions at low temprature

I am talking about thermal ionization, Is to possible to make any material
or is there any element that can be ionized at let say 20 degree
centigrade Temperature?
I am a computer engineer and into science that much but it is just
curiosity, Please correct me If I am talking nonsense.
EDIT :
As per I know a filament of a bulb produces photons when heat applied. My
point is can we make any material that will produce photons at less than a
room temperature and use photoelectric effect to capture energy of photon
and convert it to electricity.