Protonoit

Protonoit is a synthetic inorganic material noted for its high proton conductivity when hydrated and its stability under humid air. It is studied as a potential solid-state electrolyte for low-to-moderate temperature devices, including fuel cells and electrolysis cells, where efficient proton transport is essential.

Its structure comprises a three-dimensional oxide framework in which protons occupy interstitial sites within hydrogen-bond networks. The lattice provides short migration paths, allowing rapid proton transfer via a Grotthuss-like mechanism. The material typically forms layered or perovskite-related phases depending on composition.

Synthesis methods include solid-state reactions of metal oxides followed by treatments in hydrogen-rich atmospheres, hydrothermal routes, or high-temperature intercalation of protons. Doping with aliovalent cations is common to tune defect chemistry and adjust conductivity, activation energy, and hydration behavior.

Protonoit shows conductivities on the order of 10^-3 to 10^-2 siemens per centimeter under humid conditions at temperatures between 40 and 120°C, with activation energies around 0.25–0.35 eV. Its hydration-dependent conductivity and moisture sensitivity are central design considerations for device integration.

Current research focuses on improving chemical stability, long-term performance, and compatibility with electrode materials. While promising, practical deployment requires scalable synthesis and robust interfaces. Protonoit remains a topic of active investigation within the broader field of proton-conducting electrolytes.