What happens to molecules that are adsorbed on the surface of a nanoparticle when a very intense but short, laser electric field impinges on the complex? This is a question of profound and actual importance in the fields of nanosciences and nanotechnology. We have recently developed a spectroscopic framework to study and understand the dissociation of organic molecules on nanoparticles caused by the locally enhanced electric field from few-cycle intense laser pulses. The nanoscope is an instrumental development where individual particles are entered from atmospheric pressure into the ion source of a mass spectrometer held in an ultrahigh vacuum. Molecules such as water or ethanol, or others, adsorbed on the surface are then dissociated and ionized on individual particles by the laser pulse and the mass and abundance of the fragments are determined, shedding light on different possible channels of dissociation. To reveal where on the surface of the individual particles these reactions take place with nanometric precision, at the fs and sub fs time scale, we numerically reconstruct the classical trajectories of the ions hitting the spatially resolved detector to successfully backtrack the place of their formation. With this new technique, we aim to clarify basic aspects of the catalytic properties of different types of nanoparticles, an achievement of potential great future impact.
Selected recent publications:
2nd April 2020