Exceeding the limit of plasmonic light trapping in textured screen-printed solar cells using Al nanoparticles and wrinkle-like graphene sheets

The solar cell market is predominantly based on textured screen-printed solar cells. Due to parasitic absorption in nanostructures, using plasmonic processes to obtain an enhancement that exceeds 2.5% of the short-circuit photocurrent density is challenging. In this paper, a 7.2% enhancement in the photocurrent density can be achieved through the integration of plasmonic Al nanoparticles and wrinkle-like graphene sheets. For the first time, we experimentally achieve Al nanoparticle-enhanced solar cells. An innovative thermal evaporation method is proposed to fabricate low-coverage Al nanoparticle arrays on solar cells. Due to the ultraviolet (UV) plasmon resonance of Al nanoparticles, the performance enhancement of the solar cells is significantly greater than that from Ag nanoparticles. Subsequently, we deposit wrinkle-like graphene sheets over the Al nanoparticle-enhanced solar cells. Compared with planar graphene sheets, the bend carbon layer also exhibits a broadband light-trapping effect. Our results exceed the limit of plasmonic light trapping in textured screen-printed silicon solar cells. Solar cells: Nanostructure enhancement The performance of screen-printed silicon solar cells can be enhanced by aluminium nanoparticles. Xi Chen and co-workers from the Swinburne University of Technology in Australia report that light scattering effects can increase a solar cell’s short-circuit photocurrent density by up to 6.3%. Aluminium nanoparticles are advantageous because their Fano resonance, unlike those of gold or silver nanoparticles, falls in the ultraviolet wavelength band. This means that detrimental Fano interference effects between scattered and unscattered light can be avoided within the solar cell’s spectral range of operation. The addition of wrinkle-like graphene sheets further improves the photocurrent to 7.3% beyond that of an unmodified screen-printed cell.