Atomic layer deposition of Pt nanoparticles on low surface area zirconium oxide for the efficient base-free oxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid

The oxidation of 5-hydroxymethylfurfural (5-HMF) to 2,5-furandicarboxylic acid (2,5-FDCA) under base-free condition is one of the most attractive reactions. This work first reported the synthesis of highly efficient oxidation of 5-HMF to 2,5-FDCA catalyst using the atomic layer deposition (ALD) to deposit Pt nanoparticles on low surface area zirconium oxide (ZrO₂). Pt/ZrO₂ synthesized by ALD showed excellent activity for the oxidation of 5-HMF to 2,5-FDCA in base-free solution compared with Pt/MO_x synthesized by other methods in this work or reported already. The highly dispersed and uniform particle size of Pt particles were demonstrated by transmission electron microscopy (TEM), X-ray diffraction (XRD) and temperature programmed desorption of CO (CO-TPD), which provided a striking improvement of the catalytic activity in the oxidation of 5-HMF. An enhanced C[dbnd]O adsorption property of Pt/ZrO₂ obtained by ALD was also characterized by CO-TPD. The enhanced adsorption property of C[dbnd]O facilitated a stronger adsorption between catalyst and reactant/intermediates, which associated with the high dispersion and uniform particle size distribution of Pt particles to make the adsorbed reactant be efficiently converted to 2,5-FDCA.