Low-Dimensional Chemistry

小型化已经成为现代技术的一个常见方面：每年，笔记本电脑变得更薄，移动的手机变得更小，计算机变得更快，因为越来越多的组件可以容纳在它们的芯片上。纳米科学作为一门科学学科的出现是由电子设备行业在过去四十年中对更快芯片的不懈追求所推动的。小型化的重要性不仅在于较小的设备可以更紧密地组装在一起，当物体变得非常小时，它们有时会获得由相同材料形成的较大物体通常不会表现出的全新特性。使用催化剂来加速化学反应已经超过世纪，并且许多催化剂由负载在陶瓷上的金属颗粒组成。几十年来，汽车尾气中的催化转化器一直使用金属纳米颗粒-尺寸为数十亿分之一米的颗粒-来清洁废气，因为催化活性已被发现通过活性金属的小尺寸显着增加。当半导体形成相同尺寸的结构时，它们获得了全新的光学特性，这纯粹是因为它们的小尺寸-例如，它们在电流刺激下发出明亮的光，并且发出的光的颜色由颗粒的大小决定（因此可以高精度地控制）。这些现象被称为低维现象：它们是新的、意想不到的现象，仅仅是由于活动物体的小尺寸造成的。在一个非常重要的意义上，生物物体也可以说是低维的。细胞是由涉及少量分子的过程驱动的微小物体。生物学家已经认识到，单分子与大分子群有很大的不同，因此人们对研究它们很感兴趣，因为它们可以帮助我们更好地理解更大的系统是如何工作的。然而，没有建立的工具来构建相互作用的单分子系统，即所谓的低维系统。为了实现这一目标，需要新的工具，而本计划的目标就是开发这些工具。我们希望建立一个合成的低维系统，其中将包含生物分子及其合成模型，复制细菌的光合作用途径。光合作用是地球上所有生命的基础，因此它具有根本的重要性。然而，还有其他重要的动机来研究生物有机体收集阳光并利用它来生活，生长和繁殖的惊人有效过程。目前对化石燃料短缺的担忧，以及与燃烧化石燃料产生的二氧化碳相关的问题，使太阳能成为许多紧迫问题的极具吸引力的解决方案。为了最好地利用大量的太阳能，福尔斯落在地球上，即使在寒冷的气候像英国，我们可能会做得很好，向大自然学习。通过建立一个基于船的系统，复制生物有机体的光合作用行为，我们将获得关于自然光合作用如何工作的新见解。然而，不仅如此，我们还将开发全新的、受生物启发的设计原则，这些原则可能有助于理解许多其他科学和工程问题。在基本层面上，生物系统的工作方式与电子设备完全不同：它们由复杂的信号驱动，它们是模糊的和概率性的，而微系统基于二进制逻辑并且是精确确定的。构建一个能复制细胞通路的低维系统，需要在人造结构中采用这些非常不同的设计原则。如果我们能够实现这一点，它可能会产生重要的新见解，如何将类似的原则应用于其他技术。

Miniaturisation has become a familiar aspect of modern technology: every year, laptops get thinner, mobile phones get smaller, and computers get faster as more and more components can be accommodated on their chips. The emergence of nanoscience as a scientific discipline has been driven by the relentless quest by the electronic device industry over the past four decades for ever-faster chips. The importance of miniaturisation is not just in the fact that smaller devices can be packed more closely together, however: when objects become very small indeed, they sometimes acquire entirely new properties that larger objects formed from the same materials do not normally exhibit. Catalysts have been used for over a century to accelerate chemical reactions, and many catalysts consist of metal particles supported on ceramics. For several decades, catalytic converters in car exhausts have used metallic nanoparticles - particles a few billionths of a metre in size - to clean the exhaust gas because the catalytic activity has been found to be dramatically increased by the small size of the active metal. When semiconductors are formed into structures of the same size, they acquire entirely new optical properties purely as a consequence of their small size - for example, they glow brightly when stimulated by electrical current, and the colour of the light emitted is determined by the size of the particle (and can thus be controlled with high precision). These phenomena are referred to as low-dimensional ones: they are new, unexpected phenomena that result only from the small size of the active objects.There is a very important sense in which biological objects may also be said to be low-dimensional. Cells are tiny objects that are driven by processes that involve small numbers of molecules. Biologists have recognised that single molecules are quite different from large groups of molecules, and there has therefore been a lot of interest in studying them, because they may help us to understand much better how larger systems work. However, there are no established tools for building systems of interacting single molecules, what might be called low-dimensional systems . New tools are required to achieve this, and the goal of this programme will be to develop them.We wish to build a synthetic low-dimensional system, which will incorporate biological molecules and synthetic models for them, that replicates the photosynthetic pathway of a bacterium. Photosynthesis is the basis for all life on earth, so it has fundamental importance. However, there are important other motivations for studying the marvellously efficient processes by which biological organisms collect sunlight and use it to live, grow and reproduce. The current concerns about shortage of fossil fuels, and the problems associated with the carbon dioxide produced by burning them, make solar energy a highly attractive solution to many pressing problems. To best exploit the huge amount of solar energy that falls on the earth, even in colder climates like the UK, we may do well to learn from Nature. By building a ship-based system that replicates the photosynthetic behaviour of a biological organism, we will gain new insights into how Natural photosynthesis works. More than that, however, we will develop entirely new, biologically-inspired design principles that may be useful in understanding many other scientific and engineering problems. At a fundamental level, biological systems work quite differently from electronic devices: they are driven by complex signals, they are fuzzy and probabilistic, where microsystems are based on binary logic and are precisely determined. The construction of a functioning low-dimensional system that replicates a cellular pathway will require the adoption, in a man-made structure, of these very different design principles. If we can achieve this it may yield important new insights into how similar principles could be applied to other technologies.