SiFi - Singlet Fission photon multiplier film to increase photovoltaic efficiency

SIFI项目建议展示剑桥大学科学家团队最近取得的一项突破应用的技术和商业可行性：一种利用有机材料中的单重态裂变(SF)原理的光子倍增薄膜，与高效的无机纳米粒子发射器相耦合，将通过将薄膜改造到先前安装的模块上或通过将薄膜集成到新模块中来提高光伏模块的效率。光子倍增膜将高能光子(紫外线、蓝色和绿色)分成两个较低能量的红外光子，从而在原则上使高能光子产生的光电流加倍。当光子倍增器膜应用于先前部署的光伏组件时，它提高了组件的效率，而不会增加诸如机械安装、布线、逆变器等系统成本的平衡，因此是从相同安装的组件区域产生更多电力的一种非常有效的方式。这一好处同时降低了发电成本，增加了可再生能源的发电量，从而减少了不必燃烧如此多化石燃料的碳排放，并增强了电力供应的安全性，因为更多的电力是在当地生产的，这减少了国家对进口燃料或电力的能源依赖。SIFI试图展示一个重要的技术可行性里程碑：一种实用的光子倍增器膜，能够在“光子碰撞”或100%的外部量子效率下运行。换句话说，胶片每吸收一个高能可见光光子，就会发射一个红外线光子。这距离理论上的最大量子效率200%还差一半。该团队此前曾在去年报告了一项突破，在模型系统中，将单个高能光子转化为两个低能光子的四步过程中的前三步显示出接近最高效率的操作。该项目要解决的挑战是提高最后一步的效率--即从保存其能量的无机纳米粒子发出红外光子的发光。这项技术工作与与Eight19 Ltd合作的更广泛的工作计划相结合，Eight19 Ltd带来了有机和混合薄膜大面积加工方面的专业知识，以及基于科学创新的新光伏产品开发方面的专业知识。

The SiFi project proposes to demonstrate the technical and commercial feasibility of an application of a recent breakthrough by a team of scientists at Cambridge University: a photon multiplier film employing the principle of singlet fission (SF) in an organic material coupled to an efficient inorganic nano-particle emitter that will increase the efficiency ofphotovoltaic modules either by retrofit of the film onto previously installed modules or by integration of the film into new modules. The photon multiplier film splits high-energy photons (in the uv, blue and green) into 2 lower-energy infrared photons, thus enabling, in principle, a doubling of the photocurrent generated from the high-energy photons. When the photon multiplier film is applied to previously deployed photovoltaic modules it increases the efficiency the modules without adding to the "balance of system" costs such as mechanical mounting, wiring, inverters etc. and is thus a highly effective way of generating more power from the same installed module area. This benefit simultaneously reduces the cost of electricity generated, increases the amount of power generated from renewable sources and so reduces carbon emissions from not having to burn so much fossil fuel and enhances security of electricity supplied, since more is being generated locally and this reduces national energy dependency on imported fuel or electricity. SiFi seeks to demonstrate a significant technical feasibility milestone: a practical photon multiplier film that is able to operate at "photon reakeven" or an external quantum efficiency of 100%. In other words, the film will emit one infra-red photon for every high-energy visible photon absorbed by the film. This is halfway towards the theoretical maximum quantum efficiency of 200%. The team haspreviously reported a breakthrough in the last year in which the first three steps in the four-step process of converting a single high-energy photon into two lower-energy photons were shown to be operating close to maximum efficiency in a model system. The challenge to be tackled in this project is to raise the efficiency of the last step - that is luminescence of infra-red photons from the inorganic nanoparticle in which their energy is held. This technical work is integrated within a broader programme of work in collaboration with Eight19 Ltd, who bring expertise in large-area processing of organic and hybrid films, and in development of new photovoltaic products based on scientific innovation.