title: Fractal growth of platinum electrodeposits revealed by in situ electron microscopy.
abstract: Fractals are commonly observed in nature and elucidating the mechanisms of fractal-related growth is a compelling issue for both fundamental science and technology. Here we report an in situ electron microscopy study of dynamic fractal growth of platinum during electrodeposition in a miniaturized electrochemical cell at varying growth conditions. Highly dendritic growth - either dense branching or ramified islands - are formed at the solid-electrolyte interface. We show how the diffusion length of ions in the electrolyte influences morphology selection and how instability induced by initial surface roughness, combined with local enhancement of electric field, gives rise to non-uniform branched deposition as a result of nucleation/growth at preferred locations. Comparing the growth behavior under these different conditions provides new insight into the fundamental mechanisms of platinum nucleation.
authors.affiliation: Center for Nanoscale Materials, Nanoscience and Technology Division, Argonne National Laboratory, Argonne, IL 60439, USA. miller@anl.gov.
authors.forename: Lifen
authors.initials: L
authors.lastname: Wang
authors.affiliation: Center for Nanoscale Materials, Nanoscience and Technology Division, Argonne National Laboratory, Argonne, IL 60439, USA. miller@anl.gov.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Wen
authors.affiliation: Center for Nanoscale Materials, Nanoscience and Technology Division, Argonne National Laboratory, Argonne, IL 60439, USA. miller@anl.gov.
authors.forename: Huaping
authors.initials: H
authors.lastname: Sheng
authors.affiliation: Center for Nanoscale Materials, Nanoscience and Technology Division, Argonne National Laboratory, Argonne, IL 60439, USA. miller@anl.gov.
authors.forename: Dean J
authors.initials: DJ
authors.lastname: Miller