Cryogenic hydrogen diode

Unmet Need: Efficient hydrogen cooling

Increasing the efficiency of hydrogen liquefaction is critical to the use of hydrogen as a clean fuel. Upon cooling, hydrogen undergoes a spin conversion from mainly orthohydrogen to mainly parahydrogen preceding condensation. Unfortunately, this conversion is very slow and produces heat which complicates efficient hydrogen cooling.

The Technology: Solid-state diode promoting spin conversion of hydrogen leading to cooling

The inventors have developed a method to promote the necessary spin conversion while removing the energy produced from the spin conversion, resulting in more efficient hydrogen cooling and liquefaction. The inventors developed a solid-state diode with a voltage potential corresponding to the energy required to promote ortho-para spin state conversion in hydrogen, which allows for controlled cooling or heating of adsorbed hydrogen depending on the applied potential.


  • Hydrogen liquefaction
  • Utilization of waste heat


  • Efficient refrigeration
  • Energy conversion
  • Solid-state cooling

Patent Information:

Provisional patent filed

Learn More

Scott Steiger
Associate Director
Washington State University
(509) 335-7065
Reference No: TECH-22/3469


Jacob Leachman
John Mccloy
Matthew McCluskey
Scott Beckman

Key Words

Advanced Materials