Ultra small gold nanoparticles (GNPs) also called gold nano clusters (GNCs) because of their unique structure comprises of very few atoms and are capable of molecular level interactions by virtue of their molecule like properties. Introduction of GNCs to assist the transport layer of organic solar cells fetched higher current output as compared to cells with GNPs and cells with no gold at all. GNC devices showed a maximum efficiency enhancement by a factor of 1. 74 to that of reference cell without gold. Faster electron-hole separation and movement towards respective electrodes leads to better efficiency and we suggest that electronic properties of GNCs enhance the action of transport layer PEDOT:PSS. But GNCs give more to the solar cell. They also allow more light to pass through them, thus, allowing more light to reach the active layer via transport layer, leading to increase in photocurrent resulting in overall parameter enhancement. It was evident with our experiments that single layer of GNCs provides double benefits of transport enhancement and absorption enhancement adding up to increased cell parameters and efficiency keeping the low cost advantage of organic solar cells intact.

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Nanoclusters Gold Nanoparticles Organic Cells Current Density