Theoretically yes, it depends on the intention of said spacecraft. If you mean a stationary facility in orbit around a planet, absolutely. (By today's standard) If you intend to use it as propulsion across astronomical distances, that is where it gets tricky In terms of combustion. However it is speculated it could suffice in Ion displacement, but it would not be able to do it alone. It will need another substance to which "Excite" the substance into releasing saod Ions. A viable substance for a nuclear catalyst is the He3 isotope. ( He3 is something I am interested in perusing) Look up "Alcubierre Drive"