Ultrafast Action Spectroscopy of Hybrid States for Soft Optoelectronic Materials Engineering

现代光电材料发展的一个核心挑战是以高时间分辨率和空间选择性来控制和控制其电子和结构动力学的能力。这对于可溶液加工的“软”纳米材料越来越重要，其中电子和结构动力学是高度纠缠和时间依赖的。这种纠缠导致不同电子和振动能级的杂化以及新状态的出现，这些新状态最终决定了材料的光电特性，并在从电荷光生和激子裂变到电子态的局域化和倍增的一系列过程中发挥关键作用。一种能够表征杂化态操作的技术将是材料工程和器件开发不可或缺的。在过去的8年里，我的团队已经揭示了电子和振动态之间的杂化在一系列软电子纳米材料中的作用。我们还开发了一套新的方法，在工作条件下的纳米器件的超快光谱。这使我们处于一个独特的位置，联合收割机结合这种专业知识与相干多维光谱和多功能纳米探针平台的最新发展，开发一种新的工具包，用于光电材料中电荷动力学的时间分辨操作映射，包括演化混合态及其分子起源。这将通过有针对性地调整电子和振动态的密度、态间耦合和结构动力学，为工程材料特性开辟新的可能性。这些发现将为软分子材料中的电子过程带来新的机械理解，并可能对实际应用产生直接影响，包括开发具有高开路电压的光电子器件，发射可印刷材料或高效和坚固的太阳能燃料设备。

A central challenge in the development of modern optoelectronic materials is the ability to characterise and control their electronic and structural dynamics with high time resolution and spatial selectivity. This is increasingly important for solution processable 'soft' nanomaterials where the electronic and structural dynamics are highly entangled and time dependent. This entanglement leads to the hybridisation of different electronic and vibrational levels and the emergence of new states that ultimately determine the materials' optoelectronic properties and play the key role in a range of processes from charge photogeneration and exciton fission to the localisation and multiplication of electronic states. A technology capable of characterising hybrid states operando would be indispensable for material engineering and device development.In the last 8 years, my team has exposed the role of hybridisation between electronic and vibrational states in a range of soft electronic nanomaterials. We have also developed a new set of methods for the ultrafast spectroscopy of nanodevices at working conditions. This brings us in a unique position to combine this expertise with recent developments in coherent multidimensional spectroscopies and versatile nanoprobe platforms, to develop a novel toolkit for time-resolved operando mapping of charge dynamics in optoelectronic materials, including the evolution hybrid states and their molecular origins. This will open new possibilities in engineering material properties by the targeted adjustments of the densities of electronic and vibrational states, interstate couplings and structural dynamics. These findings will bring a new mechanistic understanding of electronic processes in soft molecular materials and can have direct consequences for the practical applications, including the development of photovoltaics with high open-circuit voltage, emissive printable materials, or efficient and robust solar fuel devices.