Use of plasmonic nanoparticles made of aluminum and alloys of aluminum to enhance the optoelectronic performance of thin-film solar cells

This computational study highlights the importance of aluminum and alloys of aluminum nanostructures to enhance the opto-electronic performance of thin-film solar cells. Despite having favorable optical properties and significant potential to enhance the performance of thin-film solar cells, not much work has been reported on the utility of using aluminum due to its high chemical reactivity. Hence, this study attempts to devise novel ways to overcome the chemical instability of aluminum while still harnessing its favorable optical properties by constructing alloys of aluminum with other metals in different ratios. Initially, single nanoparticles of Ag, Au and Al were analyzed where Al showed optimum results. Subsequently, dimer nanostructures were designed for the same materials and the Al-Al dimer coupled to the surface of Si thin-film solar cells generated the highest values in the performance parameters. Thereafter, alloys of aluminum were designed comprising aluminum-gold (Al-Au) and aluminum-silver (Al-Ag) with varying composition of materials in the alloy. It was seen that the dimer nanostructures where each of the individual nanoparticles were alloys of aluminum showed the optimum performance parameters from the thin-film solar cells. It was observed that increasing the amount of Au in the Al-Au alloy dampened the favorable optical properties of the Al only to a limited extent while potentially adding more chemical stability. This was regarded as a reasonable trade-off and supported the goals of this study.