Dagar Ritika, Zhang Wenbin, Rosenberger Philipp, Linker Thomas M, Sousa-Castillo Ana, Neuhaus Marcel, Mitra Sambit, Biswas Shubhadeep, Feinberg Alexandra, Summers Adam M, Nakano Aiichiro, Vashishta Priya, Shimojo Fuyuki, Wu Jian, Vera Cesar Costa, Maier Stefan A, Cortés Emiliano, Bergues Boris, Kling Matthias F
Faculty of Physics, Ludwig-Maximilians-Universität Munich, D-85748 Garching, Germany.
Max Planck Institute of Quantum Optics, D-85748 Garching, Germany.
Sci Adv. 2024 Aug 9;10(32):eadp1890. doi: 10.1126/sciadv.adp1890. Epub 2024 Aug 7.
Surface charges play a fundamental role in physics and chemistry, in particular in shaping the catalytic properties of nanomaterials. However, tracking nanoscale surface charge dynamics remains challenging due to the involved length and time scales. Here, we demonstrate time-resolved access to the nanoscale charge dynamics on dielectric nanoparticles using reaction nanoscopy. We present a four-dimensional visualization of the spatiotemporal evolution of the charge density on individual SiO nanoparticles under strong-field irradiation with femtosecond-nanometer resolution. The initially localized surface charges exhibit a biexponential redistribution over time. Our findings reveal the influence of surface charges on surface molecular bonding through 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 health care.
表面电荷在物理和化学中起着基础性作用，尤其是在塑造纳米材料的催化特性方面。然而，由于涉及的长度和时间尺度，追踪纳米级表面电荷动力学仍然具有挑战性。在此，我们展示了利用反应纳米显微镜对介电纳米颗粒上的纳米级电荷动力学进行时间分辨的方法。我们呈现了在飞秒 - 纳米分辨率的强场辐照下，单个SiO纳米颗粒上电荷密度的时空演化的四维可视化。最初局域化的表面电荷随时间呈现双指数重新分布。我们的研究结果通过量子动力学模拟揭示了表面电荷对表面分子键合的影响。我们进行了半经典模拟以揭示扩散和电荷损失在表面电荷重新分布过程中的作用。在单纳米颗粒水平上理解纳米级表面电荷动力学及其对化学键合的影响，有助于提升满足可再生能源和先进医疗保健领域全球需求的能力。
