COx-free hydrogen production from ammonia on novel cobalt catalysts supported on 1D titanate nanotubes. (15th November 2019)

• Record Type: Journal Article
• Authors: Lara-García, Hugo A.; Mendoza-Nieto, J. Arturo; Pfeiffer, Heriberto; Torrente-Murciano, Laura
• Is Part Of: International journal of hydrogen energy. Volume 44:Number 57(2019)
• Page Start: 30062
• Page End: 30074
• Publication Date: 2019-11-15
• Subjects: Co-based catalyst -- Ti-NT -- Ammonia decomposition -- Hydrogen production; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2019.09.120
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Hydrogen storage in chemical bonds such as ammonia is an attractive alternative to physical hydrogen storage if a sustainable and efficient catalyst can be designed for the release of COx-free hydrogen on demand. This paper presents a systematic study for the design of cobalt-based catalysts, moving away from scare Ru-based systems. It demonstrates the importance of the preparation method of cobalt-based catalysts not only to tune the size of the active species and their interaction with the support but also in the promotion of active species. Cobalt supported on titanate nanotubes via an ion-exchange method leads to the incorporation of the cobalt into the crystal structure of the titanates facilitating the formation of unreducible cobalt titanate species with a detrimental effect on the reactivity, and the thermal stability of the titanate support. Considerably higher reactivities can be achieved by loading cobalt via deposition-precipitation with NaOH method, leading to the formation of reducible cobalt particles on the surface of the titanate nanorods support. In this case, the rate of reaction is inversely related to the cobalt particle size, pointing out the key effect of particle size of cobalt-based catalyst for the hydrogen production in ammonia decomposition. Although the activities reported here for cobalt-based catalysts are still below those of the state-of-the-art ruthenium counterpart systems, this work provides unique insights for the future development of sustainable catalysts for the use of ammonia as hydrogen vector. Highlights: High H2 production from ammonia on cobalt-based catalysts. Guidance for future cobalt-based catalysts development to replace scarce Ru. Cobalt particle size plays a key parameter on ammonia decomposition activity. Cobalt catalyst preparation method affects its size and interaction with support. Strong-cobalt support interaction leads to formation of unreducible and inactive species.