Probing and enhancing charge generation and transport in solid-state dye-sensitized solar cells

光伏装置可以收集太阳提供的能量，作为清洁、可再生的电力来源具有巨大的潜力。尽管如此，对光电发电的吸收还不是很强，很大程度上是因为基于许多现有技术的设备仍然过于昂贵。一种有希望的替代方案是基于染料敏化金属氧化物介孔电极的有机-无机混合电池，这种电池生产成本更低，功率转换效率超过11%。然而，人们对掺入氧化还原活性液体电解质仍然存在担忧，存在有毒、腐蚀性化学品泄漏的可能性。最近一项用固态空穴传输体取代液态电解质的研究已经产生了高达5%功率转换效率的电池。在这里，我们提出了一个结构化的研究计划，将导致全固态染料敏化太阳能电池（SDSCs）的功率转换效率提高到含有电解质的同类产品。特别是，我们将使用一种新的方法来建立优化基本参数的标准，如电极的纳米级形貌，空穴转运体的电荷迁移率和界面处的能级排列。该研究将结合设备测量和一系列时间分辨光谱调查来推断系统的每个变化如何影响材料中的单个光物理过程（如光激发电子转移），以及这如何转化为设备操作的效率。工作将基于材料组件的精心选择，每次只允许调整一个特定的属性。这种组合的新方法不仅可以对特定的SDSC设计进行重大改进，而且还可以为成功优化方法的确切要求提供更通用的框架。

Photovoltaic devices that harvest the energy provided by the sun have great potential as clean, renewable sources of electricity. Despite this, uptake of photovoltaic energy generation has not been strong, largely because devices based on many current technologies are still too expensive. One promising alternative is given by organic-inorganic hybrid cells based on dye-sensitised metal oxide mesoporous electrodes, which are cheaper to produce and have reached power conversion efficiencies of over 11%. However, there remain concerns about the incorporated redox active liquid electrolyte, presenting the possibility of toxic, corrosive chemicals leakage. Recent research into replacing the liquid electrolyte with a solid-state hole-transporter has yielded cells with up to 5% power conversion efficiency. Here we propose a structured research programme that will lead to increases in the power conversion efficiencies of all-solid-state dye-sensitized solar cells (SDSCs) towards that of their electrolyte-containing counterparts. In particular, we will use a new approach in order to establish criteria for optimization of essential parameters such as the nanoscale morphology of the electrodes, the charge-mobility for the hole-transporter and the energetic level arrangement at the interface. The study will combine device measurements with a range of time-resolved spectroscopic investigations to deduce how each change to the system affects individual photophysical processes (such as photo-excited electron transfer) in the material, and how this translates into efficiency of device operation. Work will be based on a careful selection of material components that allow tuning of only one particular property at a time. This combined new approach will not only allow significant improvements to be made to specific SDSC designs, but also deliver a more general framework for the exact requirements of successful optimization approaches.