Applying Long-lived Metastable States with Switchable Functionality via Kinetic Control of Molecular Assembly - a Programme in Functional Materials

当前化学领域最重要的领域之一是开发新的材料，这种材料能够对当地环境的变化做出快速而可靠的反应，并发出信号让我们知道正在发生什么。这些“智能”材料可以在各种情况下用作传感器，并用于现代生活的许多方面，从按压贴片测量病人的温度到现代电视中的固态电子元件。用于开发这种材料的巧妙化学技术可以帮助材料在适当的情况下具有适当的性质——它们可以被调节。这位化学家的目标是生产出新的、智能的、反应灵敏的材料，这些材料将被制造成实际应用的有用设备。为了生产新的、更好的、更节能的材料，使英国制造业受益，并使英国保持在技术发展的前沿，我们需要找到控制分子特性和功能的新方法，以生产“更智能”的材料。这个提议的目的就是要做到这一点，使用一种调整材料特性的新方法。大多数智能材料在平衡状态下运行，而大多数复杂系统，如动物和人类，在非平衡状态下运行，对环境的微小变化反应更灵敏，因此可以以更复杂的方式发挥作用；事实上，如果人类以平衡的方式运作，我们所知道的生命将不复存在！我们需要刺激来保持我们的活力，我们希望通过将“非平衡”状态的想法应用于新材料的开发和操作，在开发新一代智能材料时从自己身上获得灵感。它们将以不同的方式运行，从而访问新的属性和功能。我们设计在非平衡条件下工作的新材料的新方法是使用“亚稳态”或激发态——这意味着我们刺激材料，例如用光脉冲，通过这样做，我们改变了材料的化学结构传递其特性的方式。有效地利用激发态，我们可以改变电子的行为，从而改变材料的化学性质，而不明显地改变它的化学性质！许多当前可切换的智能材料必须包含不同化学或物理成分的区域——这些缺陷对于赋予材料特性非常重要，但会产生异质材料——物理学家正在开发的“超材料”就是一个很好的例子。我们将能够引入相同的可调谐功能，但在化学均质材料中，具有控制其稳定性和性能的真正优势。为了实现这一目标，我们必须在一系列领域取得重大进展，包括设计亚稳态可切换材料的化学性质，产生能产生所需性质变化的激发态，控制这些“亚稳态激发态”，并最终将它们构建成有用的应用设备。我们的建议将使我们能够以目前不可能的方式开发控制这些亚稳态材料的特性和功能的方法。这些新材料有许多可能的应用，包括更高效的导体和依赖电子的更小型化的设备。我们还可以设想工程薄膜，通过简单地改变输入电压来提供光谱的每种颜色，从而允许智能油漆或智能织物的颜色可以根据心情或环境来选择。我们还可以开发“活性膜”，其机械性能可以主动调节，这将在医学和能源应用中很有用。从长远来看，有可能开发出具有负折射率的材料，其特殊性质意味着通过接通和关闭电流，物体显然会消失并重新出现！

One of the most important current areas in chemistry is developing new materials that are able to respond rapidly andreliably to changes in local environment, and send out signals that let us know what is happening. These "smart" materials can be used as sensors in a wide range of situations and are used in many aspects of modern life, from press-on patches to take a patient's temperature to solid-state electronic components in modern televisions. The clever chemistry used to develop such materials can help make materials with just the right property for the right situation - they can be made tuneable. The chemist aims to produce new, smart, responsive materials to be manufactured into useful devices for real applications. To produce new, better, more energy efficient materials that can benefit UK manufacturing and keep the UK at the forefront of technological developments, we need to find new ways of controlling the properties and functions of molecules to produce "even smarter" materials. This proposal aims to do just this, using a new way of tuning the properties of materials.Most smart materials operate in an equilibrium state, while most complex systems, such as animals and humans, operatein non-equilibrium states that are much more responsive to small changes in environment and can thus function in morecomplex ways; indeed, if the human race operated in equilibrium, life would cease to exist as we know it! We need stimulito keep us alive we wish to take inspiration from ourselves in developing a new generation of smart materials, by applyingthe ideas of "non-equilibrium" states to the development and operation of new materials. These will operate in differentways giving access to new properties and functions.Our new approach to designing new materials that operate in non-equilibrium conditions, uses "metastable" or excitedstates - this means that we stimulate the material, for example by a light pulse, and by doing so we change the way inwhich the chemical structure of that material delivers its properties. Effectively using excited states we can change thebehaviour of the electrons and hence the effect of the chemistry of a material without apparently changing its chemistry at all! Many current switchable smart materials must include regions of a different chemical or physical composition - these defects are very important for giving a material its properties, but produce a heterogeneous material - a good example is the "metamaterials" which physicists are developing. We will be able to introduce the same tuneable function but in chemically homogeneous materials, with real advantages for controlling their stability and performance.To achieve this, we have to make significant advances across a range of areas, including designing the chemistry ofmetastable switchable materials, generating excited states that give the desired change of property, controlling these"metastable-excited states" and eventually to build these into useful devices for applications. Our proposal will allow us to develop ways of controlling the properties and functions of these metastable materials in ways that are not possiblecurrently.There are many possible applications for these new materials including more efficient conductors and more miniaturisationof devices that rely on electronics. We can also envisage engineering thin films that will provide each of the colours of the spectrum by simply changing the input voltage, allowing smart paints or smart fabrics whose colour could be chosen to suit mood or environment. We can also develop "active membranes" whose mechanical properties can be actively tuned, which will be useful in medicine and energy applications. In the longer term there is the prospect of developingmaterials with a negative refractive index, whose special properties would mean that by switching on and off an electriccurrent, objects will apparently disappear and reappear!