Bio-inspired artificial light-harvesting antennas for enhancement of solar energy capture in dye-sensitized solar cells

Light absorption is the primary step in any photovoltaic device, therefore panchromatic light collection is a fundamental condition to maximize the efficiency of a solar cell. Indeed, the photocurrent density is directly proportional to the fraction of the light absorbed by the cell relative to the whole incoming solar flux. By mimicking the light harvesting antennas of natural photosynthetic systems it is possible to enhance the light capture of photoanodes in DSCs by using different absorbing units which funnel the incident light to the sensitizer by energy transfer. In this perspective article, bio-inspired strategies to improve the light collection efficiency of dye-sensitized solar cells (DSCs) by the antenna effect are reviewed. We provide a summary of some of the most important and recent developments in the utilization of the antenna effect to improve the photocurrent density in DSCs. This article highlights how new and innovative multi-chromophoric sensitizers can effectively broaden and enhance the absorption cross-section which enables us to produce higher photocurrent density both in liquid and solid state solar cells. The potential for development, future challenges and opportunities of this strategy are discussed.