As posted previously, many countries has developed and employed peroxide-driven torpedoes (and still operates them). For instance, Norway used the swedish TP612 and TP613 torpedoes for several dekades on both submarines, MTB's and (briefly) shore-based torpedobatteries. The TP613 was retired about ten years ago though, and remaining torpedoes and equipment was sold to Poland (where it's still in service with their submarines - ex. Norwegian "Kobben-class" as far as I know).

The high-concentrated peroxide (around 90% in torpedofuel if I remmeber correctly) sure has it's challenges in terms of logistics and handling, but of course it's fulle feasible.

Walter-turbines are not dependent of peroxide as a fuel (or vice versa - the swedish torpedoes have for example standard piston-engines), but the great advantage of the peroxide is it's quality as a "oxygen-carrier" (a litre of peroxide produces close to 600 litres of oxygen if I remember correct). Ensuring complete combustion and avoiding the bubble-trail is also important benefits.