Encapsulation of hydrogen in cadmium-exchanged zeolite rho; temperature-programmed diffusion studies

Cadmium-exchanged zeolite rho encapsulates 161 µmol g–1 of hydrogen at 100 °C and 620 µmol g–1 at 200°C, (in 2 h and at 1 atm), the highest ever observed for any zeolite at 1 atm; hydrogen-exchanged zeolite rho, however, shows negligible uptake of hydrogen, providing evidence that the cadmium ion is directly responsible for hydrogen encapsulation.