ABSTRACT
Hydrogen.generation.can.be.accomplished.via.traditional.DC.electrolysis.of.aqueous.solutions.at.temperatures.less.than.about.100°C..However,.electrolysis.of.steam. can.also.be.accomplished.at.higher.temperatures.at.the.cathode.of.electrolytic.cells. utilizing.solid.membranes..The.solid.membranes.typically.are.electronic.insulators. and.need.to.be.gas-tight.(hermetic),.but.have.the.special.property.of.being.able.to. conduct.ions.via.fast.diffusion.through.the.solid..Generally.the.cells.(cathode/electrolyte/anode). are. known. by. the. chemical. name. of. their. solid. electrolytes.. It. has. been.found.for.some.operating.hydrogen.fuel.cell.anode/electrolyte/cathode.systems. that.the.fuel.cell.reactions.at.the.electrodes.are.reversible.and.can.be.operated.in.an. electrolysis.mode..However,.reversibility.has.not.been.demonstrated.for.all.cathode/ electrolyte/anode.combinations.
