Liquid Organic Hydrogen Carriers (LOHCs): Comprehensive Comparison and Future Outlook

Amid the growing demand for a sustainable hydrogen infrastructure, this review examines various hydrogen storage systems. Special emphasis is placed on liquid organic hydrogen carriers (LOHCs), which represent a highly promising solution for chemical hydrogen storage in a decarbonized energy future. An ideal hydrogen storage medium necessitates high volumetric and gravimetric energy densities, rapid absorption and release capabilities, operation under ambient conditions, inherent safety, and balanced cost-effectiveness. LOHCs emerge as standout candidates due to their favorable volumetric density and adaptable storage conditions, offering a safer and more environmentally benign alternative to conventional high-pressure or cryogenic hydrogen storage. The review discusses the technical challenges of LOHCs, including the critical role of catalysts in their reversible hydrogenation–dehydrogenation cycles. In addition, we address historical critiques regarding LOHCs’ petroleum origins by showcasing recent advancements in their biobased synthesis from biomass, underscoring their potential for a virtuous, renewable, and circular energy chain. The inherent reusability of LOHC molecules, serving as hydrogen reservoirs without degradation during each cycle, significantly enhances their environmental sustainability. This comprehensive exploration aims to guide the development of more efficient and sustainable hydrogen integration solutions, ultimately contributing to reduced greenhouse gas emissions and a cleaner energy landscape.