Porphene: How Is It Formed?

在化学结构动力学和机理B(CSDM-B)计划的支持下，科罗拉多大学博尔德分校的Josef Michl教授将研究锌卟啉在水面上氧化聚合为二维聚合物卟烯的机理。金属卟啉是一大类新型的可调纳米材料，在纳米技术中具有广泛的应用前景，例如用于柔性分子电子学的可图案化单片电路板。拟议的机械调查旨在促进它们从实验室的好奇心转变为实用的材料，并教育和培训早期职业科学家。二维聚合物薄片因其在纳米技术方面的前景而成为当前非常感兴趣的对象，但其形成机理尚不完全清楚。含水氧化剂表面的单体锌卟啉通过去除每个单体周围的12个氢原子和形成12个新的C-C键，形成了卟烯方格。这种氧化聚合产生了数百纳米量级的巨大的单晶区，并显示出热力学和动力学控制的特征。建议使用各种工具对这种反应进行现场动力学和机理调查，如果成功，所获得的洞察力将允许进一步增加域大小和降低缺陷密度。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With the support of the Chemical Structure Dynamics and Mechanisms-B (CSDM-B) Program, Professor Josef Michl at the University of Colorado, Boulder will investigate the mechanism of oxidative polymerization of Zn porphyrin to the two-dimensional polymer porphene on a water surface. Metalloporphenes are a large family of new tunable nanomaterials which promise a variety of applications in nanotechnology, such as patternable monolithic circuit boards for flexible molecular electronics. The proposed mechanistic investigation is intended to promote their transformation from a laboratory curiosity to practically useful materials and to educate and train early career scientists. Two-dimensional polymer sheets are an object of great current interest because of their promise in nanotechnology, but the mechanism of their formation is incompletely understood. The porphene square grid arises from monomeric Zn porphyrin on the surface of an aqueous oxidant through the removal of 12 hydrogen atoms on the periphery on each monomer and the formation of 12 new C-C bonds. This oxidative polymerization produces remarkably large single crystalline domains on the order of hundreds of nanometers and shows features of both thermodynamic and kinetic control. An in situ kinetic and mechanistic investigation of this reaction using a variety of tools is proposed and, if successful, the resulting insight will permit further increase in domain size and decrease in defect density.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.