Aqueous proton transport at interfaces is ubiquitous and crucial for a number of fields, ranging from cellular transport and signaling, to catalysis and membrane science. However, due to their light mass, small size and high chemical reactivity, uncovering single proton surface transport at room temperature and in aqueous environment has so far remained out-of-reach of conventional atomic-scale surface science techniques, such as STM. Here, we use single-molecule localization microscopy techniques to resolve optically the transport of individual excess protons at the interface of hexagonal boron nitride crystals and aqueous solutions at room temperature. Our label-free approach relies on the successive protonation and activation of optically active defects at the surface of the crystal allowing us to resolve interfacial proton transport at the single molecule scale with nanometric resolution and over micrometer range. Proton trajectories are revealed as a succession of jumps between proton-binding defects, mediated by interfacial water. We demonstrate unexpected interfacial proton mobility under illumination, limited by proton desorption from individual defects. The proposed mechanism is supported by ab initio molecular dynamics simulations of defected and pristine hBN/water interface. Our observations provide direct experimental evidence at the single molecule scale that interfacial water provides a preferential pathway for lateral proton transport. Our findings have fundamental and general implications for water-mediated molecular charge transport at interfaces.
Suppressing Plasmonic Heating in Aqueous Environments with Hexagonal Boron Nitride
Eindhoven University of Technology（埃因霍温理工大学）；Institute of Complex Molecular Systems, Eindhoven University of Technology（埃因霍温理工大学复杂分子系统研究所）；Institut Fresnel, CNRS, Aix Marseille Univ, Centrale Med（法国国家科学研究中心艾克斯马赛大学中央理工马arseille学院菲涅尔研究所）；Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST（加泰罗尼亚纳米科学与技术研究所）
Impact of Monoatomic Vacancies in 2D Materials on the Performance of Magnetic Tunnel Junction Devices: Insights from Configurations and Interface Interactions
Inherent fluctuation-mediated equivalent force drives directional motions of nanoscale asymmetric particles -- Surf-riding of asymmetric molecules in thermal fluctuations
Observation of liquid-solid transition of nanoconfined water at ambient temperature
Peking University（北京大学）；City University of Hong Kong（香港城市大学）；Rice University（莱斯大学）；University of Stuttgart（斯图加特大学）；Max Planck Institute for Solid State Research（马克斯·普朗克固体研究所）
Exciton-mediated optical control of liquid-solid friction
MIPT（莫斯科物理技术学院）；Russian Quantum Center, Skolkovo（俄罗斯量子中心）；Westlake University（西湖大学）；St. Petersburg State University（圣彼得堡国立大学）；Institute of Science and Technology Austria (ISTA)（奥地利科学技术研究所）
Observation of long-lived spin order in nanoconfined water
CUNY–The City College of New York（纽约市立大学城市学院）；CUNY-Graduate Center（纽约市立大学研究生中心）；Department of Physics and Astronomy, The University of Manchester（曼彻斯特大学物理与天文系）；Photon Science Institute and National Graphene Institute, University of Manchester（曼彻斯特大学光子科学研究所和国家石墨烯研究所）；Quantum Innovation Centre, Agency for Science, Technology and Research（新加坡科技研究局量子创新中心）
