Electrochemically Activatable Liquid Organic Hydrogen Carriers and Their Applications

Abstract

Hydrogen has been chosen as an environmentally benignenergy sourceto replace fossil-fuel-based energy systems. Since hydrogen is difficultto store and transport in its gaseous phase, thermochemical liquidorganic hydrogen carriers (LOHCs) have been developed as one of thealternative technologies. However, the high temperature and pressurerequirements of thermochemical LOHC systems result in huge energywaste and impracticality. This Perspective proposes electrochemical(EC)-LOHCs capable of more efficient, safer, and lower temperatureand pressure hydrogen storage/utilization. To enable this technology,several EC-LOHC candidates such as isopropanol, phenolic compounds,and organic acids are described, and the latest research trends anddesign concepts of related homo/hetero-based electrocatalysts arediscussed. In addition, we propose efficient fuel-cell-based systemsthat implement electrochemical (de)hydrogenation of EC-LOHCs and presentprospects for relevant technologies.