Origin of excess heat generated during loading Pd-impregnated alumina powder with deuterium and hydrogen

▸ We studied heat produced by hydrogen and deuterium in Pd-impregnated alumina powder. ▸ Samples were fabricated using light and heavy water isotopes and varied the gas used for loading. ▸ Incorporation of hydrogen and deuterium influenced the amount of heat released or consumed. ▸ Pd nanoparticles appear to catalyze hydrogen/deuterium (H/D) exchange chemical reactions. ▸ Anomalous heating can be accounted for by chemical rather than nuclear reactions.