CuO Supported Ru Nanoclusters: A Highly Efficient Nanocatalyst for the Hydrolytic Dehydrogenation of Morpholine Borane

Abstract

In this study, the development of a new, efficient and economical hydrogen production system was aimed and for this purpose, ruthenium(0) nanoparticles placed on copper(II) oxide (CuO) support were synthesised as catalysts. The catalyst was thoroughly characterized by various advanced techniques including Transmission Electron Microscopy (TEM), TEM coupled with Energy Dispersive X-ray Spectroscopy (TEM-EDX), Scanning Electron Microscopy (SEM), SEM-EDX, SEM mapping, X-ray Photoelectron Spectroscopy (XPS), and X-ray Diffraction (XRD). According to the TEM analysis, the Ru(0) nanoparticles were well-dispersed on the CuO support with an average particle size of approximately 2.24 nm. The catalyst synthesised by a feasible and efficient method showed extremely high efficiency in hydrogen gas production as a result of hydrolysis of morpholine-borane (MB) complex. By interpreting the data obtained as a result of the experimental studies, the TOF value in hydrolysis reactions using Ru(0)/CuO catalyst was calculated as 44.37 min⁻¹. This value stands out as the highest catalytic activity achieved compared to similar systems reported so far in the literature. A series of kinetic studies on the catalytic hydrolysis of MB were conducted by varying the amount of catalyst/substrate and temperature and the rate law expression and activation parameters were generated by collecting the kinetic data. The apparent activation energy (Ea), activation enthalpy (ΔH‡) and activation entropy (ΔS‡) of MB hydrolysis catalyzed by Ru@CuO were calculated as 56.49 kJ mol⁻¹, 54.04 kJ mol⁻¹ and −40.07 J (mol × K)⁻¹, respectively. © 2025 Elsevier B.V.