光伏电池正极银浆用球形银粉的制备

Fabrication of Spherical Silver Powders Used for the Front Electrode Paste of Photovoltaic Battery

采用化学还原法制备光伏电池正极银浆用球形银粉,通过扫描电镜(SEM)和激光粒度仪表征了银粉的形貌和粒度,研究还原剂的种类、表面活性剂浓度以及反应时间等工艺条件对银粉粒度及形貌的影响。结果表明,采用抗坏血酸作还原剂、聚乙烯吡咯烷酮(PVP)作分散剂时,可以得到分散性好、粒度约为1.5μm的球状银粉。将该银粉制成浆料,印刷、烘干并烧结后,表征了电极形貌,用四探针电阻仪测得烧结银层的方阻<5 m?/□,可满足太阳能电池的电性能要求。

The spherical silver powders used for the front electrode paste of photovoltaic battery were prepared by chemical reduction. The morphology, particle size and dispersity of silver powders were characterized by scanning electron microscope （SEM） and laser particle size analyzer. The silver powders prepared are about 1.5μm in particle size, and well dispersed in spherical shape. The influencing factors were analyzed, such as the type of reducer, concentration of surfactant and reaction time etc. The silver powders were fabricated into the silver paste. After being sintered, the morphology and resistance of front electrode were measured. The results showed that the silver powders could meet the need of fabricating the front electrode of photovoltaic battery.