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arXiv · 2401.02621

Tracking Surface Charge Dynamics on Single Nanoparticles

Ritika Dagar·Wenbin Zhang·Philipp Rosenberger·Thomas M. Linker·Ana Sousa-Castillo·Marcel Neuhaus·Sambit Mitra·Shubhadeep Biswas·Alexandra Feinberg·Adam M. Summers·Aiichiro Nakano·Priya Vashishta·Fuyuki Shimojo·Jian Wu·Cesar Costa Vera·Stefan A. Maier·Emiliano Cortés·Boris Bergues·Matthias F. Kling
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Abstract

Surface charges play a fundamental role in physics and chemistry, particularly in shaping the catalytic properties of nanomaterials. Tracking nanoscale surface charge dynamics remains challenging due to the involved length and time scales. Here, we demonstrate real-time access to the nanoscale charge dynamics on dielectric nanoparticles employing reaction nanoscopy. We present a four-dimensional visualization of the non-linear charge dynamics on strong-field irradiated single SiO$_2$ nanoparticles with femtosecond-nanometer resolution and reveal how surface charges affect surface molecular bonding with quantum dynamical simulations. We performed semi-classical simulations to uncover the roles of diffusion and charge loss in the surface charge redistribution process. Understanding nanoscale surface charge dynamics and its influence on chemical bonding on a single nanoparticle level unlocks an increased ability to address global needs in renewable energy and advanced healthcare.

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Ritika Dagar, Wenbin Zhang, Philipp Rosenberger, Thomas M. Linker, Ana Sousa-Castillo, Marcel Neuhaus, Sambit Mitra, Shubhadeep Biswas, Alexandra Feinberg, Adam M. Summers, Aiichiro Nakano, Priya Vashishta, Fuyuki Shimojo, Jian Wu, Cesar Costa Vera, Stefan A. Maier, Emiliano Cortés, Boris Bergues, Matthias F. Kling. 2024-01-05. Tracking Surface Charge Dynamics on Single Nanoparticles. https://arxiv.org/abs/2401.02621

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