title: Exploring nanoparticle porosity using nano-impacts: platinum nanoparticle aggregates.
abstract: The porosity of platinum nanoparticles (PtNPs) is explored for the first time using tag-redox coulometry (TRC). This is achieved by monitoring the reduction of the 4-nitrobenzenethiol (NTP)-tagged PtNPs on carbon electrodes via both immobilisation and nanoimpacts. The average charge per impact is measured and attributed to the reduction of NTP adsorbed on individual PtNPs. The number of NTP molecules and thus the "active surface area" of the PtNPs is calculated and compared with two models: fully solid and porous nanoparticles, and the extent of the particle porosity is revealed. This allows a fuller understanding of the (electro-)catalytic behaviour of nanoparticles by providing insight into their porosity and "true/active surface areas".
authors.affiliation: Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, UK. richard.compton@chem.ox.ac.uk.
authors.forename: Xue
authors.initials: X
authors.lastname: Jiao
authors.affiliation: Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, UK. richard.compton@chem.ox.ac.uk.
authors.forename: Stanislav V
authors.initials: SV
authors.lastname: Sokolov
authors.affiliation: Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, UK. richard.compton@chem.ox.ac.uk.
authors.forename: Eden E L
authors.initials: EE
authors.lastname: Tanner
authors.affiliation: Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, UK.
authors.forename: Neil P
authors.initials: NP
authors.lastname: Young
authors.affiliation: Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, UK. richard.compton@chem.ox.ac.uk.
authors.forename: Richard G
authors.identifier: http://orcid.org/0000-0001-9841-5041
authors.initials: RG
authors.lastname: Compton