Supported metal nanoparticles play an important role in areas such as energy storage/conversion and catalysis for sustainable production of fuels and chemicals . In heterogeneous catalysis, particle size, structure and distribution of the active sites within the porous support have significant impact on the catalytic properties . To better clarify the influence on the catalytic property, an insight into the three-dimensional (3D) structure of supported catalyst is indispensable. Electron tomography in combination with image analysis has been demonstrated to provide 3D information at the nanoscale. In the present work, we focus on two aspects: the 3D morphology of the support and the distribution of the active metal sites. For the first part, the 3D structure of two porous carbon supports (a synthesized mesoporous carbon (MC) and a commercial ordered porous material (CMK-3)) have been quantitatively analyzed by electron tomography with advanced image analysis. Quantitative information including pore size, pore orientation, tortuosity and connectivity have been obtained for a full morphological description of the two carbon supports. For the second part, quantitative electron tomography analysis revealed the 3D distribution of Pd nanoparticles on Pd/CMK-3 catalysts prepared by different approaches (incipient wetness impregnation, wet impregnation and immobilization of preformed PVA stabilized nanoparticles). The observed distribution of the nanoparticles was critical to understand their catalytic properties (reactivity & selectivity) in furfural hydrogenation.
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