Spectral Conversion Materials to Harvest Sunlight in the Urban Landscape

Dr Rachel C. Evans

Solar power is the world’s fastest-growing energy source. The sun rush has driven technological advances and forced competitive manufacturing, leading to more efficient solar cells at significantly reduced costs. Central to the argument for solar technologies is the potential to tap in to an essentially infinite reserve - more energy from the sun hits the Earth’s surface in an hour than the global population uses in an entire year! However, sunlight arrives as a broad distribution of photons with different energies, and current solar cells are unable to harvest all of these photons efficiently. This restricts the maximum achievable performance of any solar device.
To tackle this challenge, luminescent spectral converters have emerged as a rational strategy to harvest otherwise wasted solar photons, providing a way to optimise the spectral response of any solar cell. Spectral converters can be integrated directly with finished solar cells, which avoids the need for modifications to the device physics. Furthermore, the colour tunability of spectral converters, combined with their ability to enhance the response of solar cells to diffuse light have been regarded as effective drivers for a truly sustainable transition towards wide-scale deployment of solar harvesting architecture in the urban landscape.
This talk will focus on our recent work to develop photoluminescent spectral conversion materials which enable the collection, conversion and concentration of sunlight for subsequent use by solar cells. The use of materials engineering to enable the bottom-up design of spectral converters with tuneable optical properties will be established and future perspectives for the advancement of this field will be discussed.