Use of nanoparticles arrays made of alloys of plasmonic metals of varying compositions to enhance the opto-electronic performance of thin-film solar cells

Abstract

The demand for the photovoltaic (PV) cells has increased exponentially in the last decade as solar energy has become extremely popular because it is environmentally friendly and relatively affordable, thus making solar energy an attractive alternative to fossil fuels. Of the many methods available to increase the efficiency/performance of PV cells, the use of plasmonic nanostructures have been have been a major focus of recent research due to their ability to significantly enhance the light absorption and other optical/electrical performance of solar cells. In this paper, plasmonic metal nanoparticles made of alloys of silver, aluminum and gold with different percentage in their composition were used to enhance the opto-electronic performance of thin-film solar cells. The alloys were studied in an attempt to harness the favorable plasmon enhancement properties of individual silver, gold and aluminum particles and create a more efficient enhancing material. The size and pitch (the edge-to-edge distance between adjacent nanoparticles in an array) of the alloy nanoparticles in an array is also varied and analyzed. The simulation results show that an alloy made of Ag-Al(10%-90%) of 100nm diameter having a pitch of 100nm gives the most favorable result when compared to other composition of the alloys or with pure metal. This conclusion was reached through the analysis of optical absorption enhancement, open circuit voltage produced, short circuit current generation, fill factor calculations, efficiency and optical near-field optical enhancement studies.