Selective photocatalytic hydrogenation of citral over pure TiO ₂ nanoparticle

Abstract The α, β-unsaturated aldehydes selective hydrogenation, especially the C=O bond, is an extremely challenging topic in the field of catalysis. In this paper, a series of pure TiO₂ photocatalysts obtained at various calcination temperature were tested for the hydrogenation of citral. It has been determined that inexpensive TiO₂ nanoparticles, calcined at 450 °C–500 °C for two hours, show hydrogenation selectivity of 100% from citral toward unsaturated alcohols (UA) with the highest conversion up to 99% under ultraviolet light. The present work reports a simple yet pragmatic approach for the efficient and selective hydrogenation of the C=O bond of citral.