Non-classical hydrogen storage mechanisms other than chemisorption and physisorption

Abstract

The hydrogen storage mechanism of materials is usually divided into chemisorption and physisorption according to the way the material interacts with hydrogen. Chemisorption refers to the breaking of hydrogen molecules into hydrogen atoms, which are then bonded to materials through chemical bonds. Physisorption refers to the adsorption of hydrogen molecules on the surface of materials with high specific surface areas through van der Waals forces. With the development of materials science and characterization techniques, some new hydrogen storage materials are emerging, which exhibit relatively complex interactions with hydrogen. This review will focus on non-classical hydrogen storage materials and mechanisms beyond physisorption and chemisorption, including Kubas interactions, nanopump effects, non-dissociative chemisorption, and weak-confined insertion of hydrides. This review will give researchers a clear view of the diversity of hydrogen storage materials and the complexity of hydrogen storage mechanisms, which may help enrich future hydrogen storage materials.