The Preparation Of Monodisperse Spherical Silver Particles And Its Application In Solar Cells

The overuse of fossil fuels and the great changes in the environmental climate raise awareness of the urgency to develop a new energy.Solar energy as a clean resource entered people’s field of vision.At present,the use of solar energy is converting it directly into electric energy by solar cells.Solar cells fall into several classes,among the numerous solar cells,silicon solar cells have been accounted for more than 90% of the world’s solar cells market due to the resource-rich,advanced technology and high conversion efficiency.And silicon solar cells will dominant the market of the photovoltaic industry in the future.In this paper,the silver particles,glass powders and organic medium for the silicon solar cells were prepared,respectively.Then,the silver paste was prepared by mixing silver particles,organic medium and glass powders.Finally,solar cells were prepared by screen printing,and the electrochemical parameters were measured.First,the ascorbic acid was selected as reduction agent,PVA was selected as dispersing agent,and the micro-sized silver particles were prepared using a simple chemical approach.The effects of temperature,reaction time and stirring speed on the morphology and size distribution of silver particles were discussed.The optimal reaction parameters were obtained:35°C,45 min and 300 rpm.Second,the glass system of PbO-SiO₂-B₂O₃ was selected,and the glass plates were prepared by melt cooling route.The particles size glass powders less than 5 μm were obtained by mechanical milling and wet ball-milling.Organic medium was prepared by using dibutyl phthalate,dimethyl adipate,dimethyl glutarate and alpha-terpineol as organic solvents,Polyamide wax and hydrogenated castor oil as thixotropy agents,triethanolamine as surfactant,and ethyl cellulose ethoce as thickening agent,respectively.The effects of different mass ratio of organic solvents,different proportion of thixotropic agents and swelling time ofthickening agent on the viscosity and thixotropic index of organic medium were studied.At last,the silver paste was prepared by mixing silver particles,organic medium and glass powders.The effect of solid content on silver grid line was studied,and the optimal solid content was determined as 85.00%.The as-prepared silver paste and purchased commercial silver paste were manually print through screen printing machine,respectively.The electrochemical parameters were measured.The photoelectric conversion efficiency of the solar cells made with silver paste by using the silver particles can reach 18.64%,which is similar to the industrial production of solar cell made with commercial silver paste.This study is contribute to guide the preparation of spherical silver particles and break the monopoly of imported products.