The catalytic transfer hydrogenation on Ni electroless alloys Original Research Article

The catalytic transfer hydrogenation (CTH) was investigated on Ni electroless alloys, using H2PO2− ion as the H-donor and 3-buten-1-ol as a model organic compound. Ni electroless alloys films containing 7, 9 and 14 at.% of P were prepared and characterized by SEM, EDS and XRD. Cyclic voltammetry allowed to evaluate qualitatively the catalyst ability to co-adsorb the H-donor and the organic compound and revealed that the adsorption ability of 3-buten-1-ol is stronger on the highest P content alloy film. The CTH performance was characterized in terms of yield, H-donor efficiency and selectivity and the results were compared to those for the electrocatalytic hydrogenation. The dependence of the catalyst activity on the P content of the Ni alloy was found to follow different trends on the two hydrogenation methodologies. This behaviour was qualitatively explained on the basis of the competitive adsorption of 3-buten-1-ol and the supplier of hydrogen. It was concluded that hydrogenation of a strong adsorbable unsaturated organic compounds is more successful through the use of an H-donor than through the electrocatalytic hydrogenation.In the course of the CTH run, the Ni alloy deactivation was observed, but re-activation of the catalyst by applying a rather negative potential was attained. Dependence of the time lag for deactivation with the P content of the Ni alloy was found. The source of the deactivation was investigated and an explanation for this phenomenon was proposed.