Application of plasmonic nanoparticles to modulate organic photochemistry

知道本世纪一些最伟大的创新--从展示最新款苹果手机到净化口罩以防止新冠肺炎传播--依赖于分子对被禁止的光激发态的访问，你会感到惊讶吗？为什么科学家会选择基于被禁止的东西进行创新？这其中有两个主要原因。第一个是这些禁态是最普遍的，因为4个激发态中有3个是禁态。但更重要的是，这些状态可以持续很长一段时间，因为它们的特性是被禁止的。这种长寿命是有利的，例如，已经跃迁到这些禁态的分子在反应之前可以旅行更长的时间，从而为某些化学反应提供了特异性。然而，不言而喻，因为这些激发态是被禁止的，它们很难达到。有机分子的情况尤其如此。出于这个原因，许多科学家在过去的几十年里一直致力于改善对这些被禁止的激发态的访问。为了实现这一点，人们已经在改变有机分子的化学结构方面做了大量的工作。虽然这是一种有效的方法，但不一定是最有利于创新的方法。事实上，修饰有机分子可能需要几个复杂的合成步骤，这可能不容易扩展。另一种不那么传统的方法是操纵光，以便于进入这些禁忌状态。这是我的研究团队考虑到我们访问、操纵和利用禁忌状态的长期目标而采取的策略。为了引导光线，我的团队计划使用等离子纳米颗粒。这些纳米粒子是一个令人着迷的工具，因为它们扮演着放大环的角色，将光线集中在它们的表面。我的研究计划的目标是，在接下来的5年里，通过将纳米技术与光化学相结合，瞄准三条被禁止的路径。我最初的计划是利用等离子体纳米粒子表面的光的磁性部分来调节对这些禁态的访问。由于这些状态对磁场非常敏感，这将允许我们操纵它们并对它们的反应性进行控制。拟议计划中计划的研究活动将是获得新的科学知识的基础，因为拟议的战略是新颖的，它们还将通过加强银行和金融系统、防伪或推进下一代计算基础设施来增强加拿大的创新能力。

Would you be surprised to know that some of the greatest innovations of this century, from the display of your newest iPhone to the decontamination of masks to prevent the spread of COVID-19, depend upon molecular access to forbidden excited states with light? Why would scientists choose to innovate based on something that is forbidden? There are 2 major reasons for that. The first one is that these forbidden states are the most prevalent ones, as 3 out of 4 excited states are forbidden. But more importantly, these states can persist for a very long time because of their forbidden character. This long lifetime is advantageous as, for instance, molecules that have transitioned to these forbidden states can travel longer before they react, providing specificity to certain chemical reactions. However, it goes without saying that, because these excited states are forbidden, they are difficult to reach. This is especially the case for organic molecules. For this reason, many scientists have focused their effort over the last decades on improving access to these forbidden excited states. To accomplish this, a lot of work has been directed at modifying the chemical structure of organic molecules. While this is a valid approach, it is not necessarily the most conducive for innovation. Indeed, modifying organic molecules might require several complex synthetic steps, which might not be easily scalable. Another approach, which is much less conventional, would be to manipulate light to facilitate access to these forbidden states. This strategy is the one my research team is adopting in view of our long-term goal to access, manipulate and utilize forbidden states. To guide light, my team plans to use plasmonic nanoparticles. These nanoparticles are a fascinating tool, as they act as magnifying loops, concentrating light at their surface. My research program aims to, over the next 5 years, target three forbidden paths by combining nanotechnology with photochemistry. My original plan is to exploit the magnetic portion of light at the surface of plasmonic nanoparticles to tune access to these forbidden states. As these states are very sensitive to magnetic fields, this will allow us to manipulate them and exert control over their reactivity. The research activities planned in the proposed program will be the foundation to new knowledge in science, as the proposed strategy is novel, they will also enhance the Canadian innovation capacity by strengthening banking and financial systems through forgery prevention or advancing the next generation computing infrastructure.