Plasmon enhanced solar cell structure based on GaAs nanowire array decorated with metal nanoparticles. The results show that the engineered metal nanoparticles can excite the local surface plasmon, so that the incident light can be gathered and the energy can be transmitted to the nanowires. Surface plasmon can significantly enhance the absorption of near Band Gap light, and the enhancement is affected by the size and material of nanoparticles. By optimizing the particle parameters, a large absorbance enhancement of 50% and a high conversion efficiency of 14.5% can be obtained at 760 nm at a low diameter and period ratio (D / P ratio) of 0.3. The structure is expected to be used in nano solar cells with low cost and high performance.
The two prominent problems faced by traditional solar cells are to reduce the cost of solar cells and improve the photoelectric conversion efficiency of solar cells. At present, commercial solar cells are mainly made of silicon materials, and silicon-based solar cells account for 80% of the current solar cell market. The thickness of traditional monocrystalline silicon solar cells is about 180-300mm, while the thickness of silicon thin film solar cells is only a few microns, which greatly reduces the consumption of silicon materials and reduces the cost of solar cells. However, the reduction of Si material thickness will reduce the photoelectric conversion efficiency of Si thin film solar cells. The latest research shows that, Using the light scattering of metal plasma and the field enhanced light aggregation generated by local plasmon resonance can effectively improve the light absorption of silicon thin film solar cells.
In this paper, the following studies are carried out:
1. In order to study metal nanoparticles reinforced silicon thin film solar cells, spherical, square and, It is found that by adjusting the shape and size of metal nanoparticles on the silicon surface, the thickness of surface SiO2 passivation layer has an effect on the light absorption of silicon thin layer. It is found that adjusting the particle size of nanoparticles can make the light absorption spectrum of silicon layer red shift and improve the light absorption in infrared band.
2. With the help of the study of metal nanoparticles on the light absorption spectrum of silicon layer, firstly, the structure of silicon thin film solar cell with spherical nano array on the upper surface and square nano array on the lower surface is designed. It is found that the spherical particle size and square particle side length can affect the light absorption of solar cell. The light absorption efficiency can be enhanced by optimizing the structural parameters of solar cell.
3. Using the antireflection and light diffraction of two-dimensional subwavelength grating