The Shape of Water: Wetting and Beyond

水是地球上最丰富的分子，然而液态水的形状一直让科学界感到困惑。对水的经典描述是，在一个四面体基序中，每个水分子通过氢键平均与另外四个水分子相连。迄今为止，这种结构已经成为理解表面润湿的基础，这需要一个有限尺寸的液滴与表征表面接触来测量其接触角。申请人最近在液滴水下润湿动力学方面的开创性工作揭示了液滴与淹没表征表面之间存在纳米级薄水膜，强调了界面水层在润湿动力学中的重要性。拟议的研究计划建立在液下滴动力学的这些进展的基础上，通过使用通过该计划开发的最先进的实验和计算工具，获得对界面水层内承压水分子形状的新的基本理解。它将探索这种受限水分子的新量子特性。这项由实验、理论和计算工作组成的基础研究将为对润湿现象的新理解铺平道路，特别是在新兴的二维材料的背景下，它可以为承压水分子的量子行为提供新的见解。这将有各种各样的工程应用，从制造具有防污性能的高效防水表面（例如，船体）到用于海水淡化的膜（例如，通过拒绝溶解的盐提供清洁水的新来源），甚至创造量子计算的新方法（例如，在室温下使用水分子进行计算）。该研究计划将培养包括博士后、研究生和大四本科生在内的11名高素质人才，目标是建立基于基础科学与工程应用研究无缝结合的训练有素的劳动力。它将为加拿大的战略优先领域（先进制造业、环境和信息通信技术）提供重要的发展机会。研究成果将为研究界提供关于润湿和界面水重要性的新视角，从而为申请人建立“量子润湿”的新研究方向。这个综合研究项目将使加拿大在开发和表征具有可调润湿性能的下一代材料方面处于国际领先地位，并将推动申请人的研究小组走在润湿领域的前沿。

Water is the most abundant molecule on earth, yet the shape of liquid water continues to mystify the scientific community. Classical depictions of water consist of each water molecule on an average bonded to four others in a tetrahedral motif by hydrogen bonding. To date, this structure has been the foundation for understanding wetting of surfaces, which requires a finite size liquid drop in contact with the characterizing surface to measure its contact angle. The applicant's recent pioneering work on underwater wetting dynamics of liquid drops revealed the existence of a nano-scale thin water film between the drop and the submerged characterizing surface, underscoring the importance of the interfacial water layer in wetting dynamics. The proposed research program builds upon these advances in under-liquid drop dynamics to gain new, fundamental understanding of the shape of the confined water molecules within interfacial water layers using state-of-art experimental and computational tools developed through this program. It will explore new quantum properties for such confined water molecules. This fundamental research consisting of experimental, theoretical and computational work will pave the way for a new understanding of wetting phenomena, particularly in the context of new emerging two-dimensional materials, and it could provide new insight into the quantum behaviour of confined water molecules. This would have a wide variety of engineering applications ranging from fabricating efficient water-repellant surfaces with antifouling properties (e.g., ship hulk) to membranes for water desalination (e.g., providing new source for clean water by rejecting dissolved salts) and even creating new ways of quantum computing (e.g., using water molecules at room temperature to perform computation). The research program will train eleven highly qualified personnel including post-doctoral fellows, graduate students and senior undergraduate students with a goal to create a trained workforce based on seamless integration of fundamental science with applied research in engineering. It would provide significant opportunities to develop skilled workforce in Canada's strategic priority areas (Advanced Manufacturing, Environment, and ICT). The research outcomes will provide the research community with new perspectives on wetting and the importance of interfacial water, thereby establishing a new research direction on "quantum wetting" for the applicant. This comprehensive research program will position Canada as an international leader in developing and characterizing the next-generation materials with tunable wetting properties and will propel the applicant's research group to the forefront of the wetting community.