Although titanium, like S/S, requires
some oxygen to form it's protective oxide film, I think it would do well in your application.
Titanium's
corrosion resistance is due to a stable, protective, strongly adherent oxide film,
which forms instantly when a fresh surface is exposed to air or moisture.
(Titanium has a very strong affinity for oxygen)
The oxide film formed on titanium is more protective than that on
stainless steel, and it often performs well in environments, such as seawater, wet chlorine, & organic chlorides, that cause pitting and crevice corrosion in stainless. While titanium is resistant to these media, it is not immune, and can be susceptible to pitting and crevice attack at
elevated temperatures. It is, for example, not immune to seawater corrosion if the temperature is greater than about 110 deg. C.