Improvement of light-harvesting efficiency of amorphous silicon solar cell coated with silver nanoparticles anchored via (3-mercaptopropyl) trimethoxysilane

Owing to small size effect and large surface area, silver nanoparticles (Ag NPs) exhibit special physical properties and are widely used in different applications. One of the significant applications is that Ag NPs can be coated on the glass surface of solar cell to increase the light-harvesting efficiency of solar cell due to the plasmonic resonance and scattering effect. In this study, Ag NPs used for the coating of solar cells were synthesized via a chemical reduction method. The effect of the concentration of sodium borohydride (NaBH4) as reducing agent and 1-dodecanethiol (DDT) as capping agent on the size and shape of Ag NPs synthesized have been investigated. The synthesized Ag NPs were characterized using UV-vis spectroscopy, X-ray diffraction, energy-dispersive X-ray spectrometry and ATR-FTIR spectroscopy; while the particle size, morphology and topology of Ag NPs were examined by scanning electron microscopy and atomic force microscopy. By coating the glass surface of amorphous silicon solar cells with a uniform array of Ag NPs with the particle size of > 350 nm, a power conversion efficiency (PCE) enhancement of approximately 41% has been achieved. (3-mercaptopropyl) trimethoxysilane (MPTMS) was used as the adhesion promoter to anchor Ag NPs on the silicon surface of solar cells. With 7% of MPTMS, the array of Ag NPs formed on the glass surface was found being the most evenly distributed with a densely packed surface coverage, which resulted in 46% of PCE enhancement of the silicon solar cells.