Enhanced catalytic properties of Pd nanoparticles by their deposition on ZnO-coated ceramic membranes

An efficient and reusable catalyst was developed by loading palladium (Pd) nanoparticles on a ceramic membrane modified with a ZnO nano-coating. The microstructures of the as-prepared Pd-loaded ceramic membranes were characterized by FESEM, EDS, ICP, XPS and HRTEM. Their catalytic properties in liquid-phase p-nitrophenol reduction to p-aminophenol were evaluated. A comparative study was also made with the Pd nanoparticles deposited onto the ceramic membrane without any modification. The XPS and HRTEM results indicate that the ZnO coating can provide strong Pd-Zn interactions on the ceramic membrane, resulting in higher catalytic stability with similar catalytic activity as compared to that without modification. It was found that the leaching and agglomeration of Pd nanoparticles should be responsible for the deactivation of Pd-loaded ceramic membranes. This work would aid the development of membrane catalysts with higher catalytic performance.