Proton ceramic reactors offer efficient extraction of hydrogen from ammonia, methane, and biogas by coupling endothermic reforming reactions with heat from electrochemical gas separation and compression. Preserving this efficiency in scale-up from cell to stack level poses challenges to the distribution of heat and gas flows and electric current throughout a robust functional design. Here, we demonstrate a 36-cell well-balanced reactor stack enabled by a new interconnect that achieves complete conversion of methane with more than 99% recovery to pressurized hydrogen, leaving a concentrated stream of carbon dioxide. Comparable cell performance was also achieved with ammonia, and the operation was confirmed at pressures exceeding 140 bars. The stacking of proton ceramic reactors into practical thermo-electrochemical devices demonstrates their potential in efficient hydrogen production.

With the increased pressure to decarbonise the power generation sector several gas turbine manufacturers are working towards increasing the hydrogen-firing capabilities of their engines towards 100%. In this review, we discuss the potential materials challenges of gas turbines fuelled with hydrogen, provide an updated overview of the most promising alloys and coatings for this application, and highlight topics requiring further research and development. Particular focus is given to the high-temperature oxidation of gas turbine materials exposed to hydrogen and steam at elevated temperatures and to the corrosion challenges of parts fabricated by additive manufacturing. Other degradation mechanisms such as hot corrosion, the dual atmosphere effect and hydrogen diffusion in the base alloys are also discussed.