Overcoming Liquid Hydrogen storage problem: Increasing the ortho-para H2 conversion yield

One of the problems faced by engineers in using the hydrogen molecule for industry (e.g., aerospace, future vehicles) concerns the storage of liquid hydrogen, where special procedures are required to keep the composition (proportion) of the two types of hydrogen molecules known as orthohydrogen (o-H2) and parahydrogen (p-H2). Without these procedures, o-H2 in the storage tanks slowly convert to p-H2 over a period of days or weeks, releasing enough heat to evaporate most of the liquid. In order to limit the boil-off to low levels, it is necessary to fill the tank with liquid hydrogen that has already been converted to an equilibrium composition close to 100 % p-H2. Thus, a method to increase the o-p H2 conversion yield is important in liquid hydrogen storage [1-2]. In this study we introduce a new method to increase the o-p H2 conversion yield on the catalysts surfaces by using: [1]. Molecular orientation of H2 on catalysts surface. One of the ultimate goals of surface science is to be able to design and control reactions as they progress on surfaces. This entails an atomic-level understanding of the fundamental principles (elementary processes) underlying, among others, the bond-making and bond-breaking at surfaces. By using steric effect (SE) and dynamical quantum filterin