Abstract： The composite powders of fly ash cenospheres plated by silver were prepared by slowly adding the solution of AgNO3 into alkaline solution with D-glucose as reducing agent after hot alkali’s activation. The morphology and composition of the silver-coated fly ash cenospheres composite powders were observed and analyzed by SEM, EDS and XRD. The mechanism of electroless silver plating on fly ash with thermo-alkaline activation was studied. The results show that the nano-crystalline silver plating is even and compact. The resistivity of the composite particles can reach 0.05 Ω·cm. The mechanism of electroless silver plating on fly ash with thermo-alkaline activation is as follows. A large number of hydroxyl groups are generated on the surface of fly ash cenospheres due to powerful reaction of alkali with SiO₂ and Al2O3, then the nucleophilic of hydroxyl groups promotes polarity attraction on silver ammonium cation, so the silver is reduced by reduction reaction of D-glucose.

Keywords: fly ash cenospheres; thermo-alkaline activation; electroless silver plating; mechanism

中图分类号：TQ153.3         文献标志码：A

文章编号：1008-5548(2015)02-0090-04

DOI:10.13732/j.issn.1008-5548.2015.02.023

收稿日期：2014-04-28， 修回日期：2014-06-11，在线出版时间：2015-04-17。

第一作者简介：李亚敏(1973—)，女，博士，副教授，研究方向为高温合金及金属表面改性。 电话：0931-2976572，E-mail：leeyamin@163.com。