Luminescent Lanthanide Layers for Enhanced Photovoltaic Performance (LEAP)

人们现在普遍认为，近几个世纪来，世界对化石燃料的日益依赖正在导致地球气候的剧烈变化。可再生能源技术--如太阳能、风能和海浪能--为清洁能源的产生提供了一条途径。该项目涉及光伏(PV)技术--将阳光转化为电能--尤其涉及将发光材料应用于光伏组件。自1994年以来，光伏组件的出货量一直在以每年40%的稳定速度增长，预计未来几年将继续保持20%-30%的强劲增长。然而，效率和价格仍然是降低太阳能发电成本的主要障碍。该项目寻求开发一种新的光伏器件和模块，基于当今的半导体技术，但在光子与太阳能电池相互作用之前，利用发光材料改变阳光中包含的波长。通过两种称为下转换(DC)和上转换(UC)的技术，我们能够极大地解决将单结太阳能电池的理论性能限制在30%左右的两个主要损耗机制。有了DC，我们能够使用发光材料吸收300-500 nm范围内的光子(从紫外光到蓝绿光)，并在大约1000 nm处发射两个光子，在那里硅太阳能电池的响应非常有效。初步模拟表明，在硅太阳能电池正面施加这样的直流层可以将其绝对能量转换效率(太阳能到电能)从典型生产设备的16%提高到19%。因此，性能上的巨大变化是可能的！UC层能够收集直接穿过硅的近红外(NIR)光，对于这些近红外光子中的每一个，我们可以发射一个更高能量的光子，可以被硅太阳能电池捕获。UC层的性能取决于太阳光的强度，因此我们将在500倍的集中阳光下设计和测试这些系统。本项目汇集了英国赫里奥特-瓦特大学(Heriot-Watt University)的光谱转换和光伏专业技术，并将其与中国科学院(CAS)福建物质结构研究所(FJIRSM)的发光材料专业知识相匹配，目标是建立一种新型光伏器件，能够保证c-Si和薄膜(例如a-Si：H)光伏技术的性能阶梯变化。

It is now widely accepted that the world's increasing reliance on fossil fuels over recent centuries is causing drastic changes in the Earth's climate. Renewable energy technologies - such as solar, wind and wave energy - offer a pathway for the generation of clean energy. This project concerns photovoltaic (PV) technology - the conversion of sunlight to electricity - and, in particular, involves the application of luminescent materials to PV modules. Shipments of PV modules have been increasing at a steady rate of >40% per annum since 1994 and continued strong growth of 20-30% predicted for the next few years. However, efficiency and price are still the main barriers to reducing the cost of solar electricity.This project seeks to develop a new class of PV devices and modules, based on todays semiconducting technology however utilising luminescent materials to alter the wavelengths contained in the sunlight before the photons interact with the solar cell. Via two techniques known as down-conversion (DC) and up-conversion (UC), we are able to greatly address two of the main loss mechanisms that limit the theoretical performance of a single junction solar cell to about 30%. With DC, we are able to use luminescent materials to absorb photons in the range of 300-500nm (UV through to blue-green light) and for each of these emit TWO photons at about 1000nm, where silicon solar cells respond very efficiently. Preliminary modelling has indicated that such a DC layer applied to the front of a silicon solar cell could increase its absolute energy conversion efficiency (sunlight to electricity) from 16% for a typical production device to 19%. Thus, a huge step change in performance is possible! UC layers are able to collect near-infrared (NIR) light that passes straight through the silicon, and for each of these NIR photons we can emit a single higher-energy photon that can be harvested by the silicon solar cell. The performance of UC layers depends on the intensity of sunlight though, and hence we will design and test these systems under 500-times concentrated sunlight.This project brings together spectral conversion and PV expertise from Heriot-Watt University (HWU) in the UK and matches this with luminescent materials expertise from the Fujian Institute of Research on the Structure of Matter (FJIRSM), one of the Chinese Academy of Sciences (CAS), with the goal of establishing a new class of PV devices that are able to promise a step-change in performance for both c-Si and thin film (e.g. a-Si:H) PV technologies.