纳米银胶的合成及其应用性能研究

Synthesis and research on application of nano-silver colloid

为了合成纳米银胶并考察其在制备导电银膜方面的应用性能，在聚乙烯吡咯烷酮（PVP）保护下，利用抗坏血酸（Vc）还原柠檬酸银纳米乳液，合成了纳米银胶，并将其用迈耶棒涂布在支持体上制备了纳米导电银膜。考察了不同Vc用量对合成纳米银胶反应程度，以及水浸泡与加热烧结两种后处理手段对银膜表面电阻的影响。XRD分析结果表明，Vc过量1倍反应进行彻底，产物纯净、无副产物；TEM与UV-Vis测试表明，合成的纳米银胶粒径分布在10～50nm，无明显团聚现象；通过对水浸泡前后银膜进行FTIR测试表明，副产物溶解使纳米银膜更加致密的排列，降低了其表面电阻；DSC、TG结果表明，纳米银的低熔点特性与有机物的分解，使得纳米银膜的表面电阻在烧结过程中大幅降低。

To investigate the applications of nano-silver colloid in conductive silver film, the nano-silver colloid was synthesized using ascorbic acid （Vc） reduce silver citrate nano-emulsion in the presence of polyvinylpyrrolidone （PVP） as a protected agent. Then the nano-silver colloid was coated onto the substrate to form a conductive silver film by Mayer rod. The influence of amount of Vc on the degree of the reaction and the effect of two kinds of post-processings, water dipping and Sintering processing, on the surface resistance were discussed. The XRD results showed that the reaction was completed when Vc excessive double; The TEM and UV-Vis study indicated that the distribution of silver colloid particles was from 10～50nm and without any particles aggregation. The FTIR results of pre-water dipping and post-water dipping showed that the densification of the silver film by dissolving away by-products decreased the surface resistance. DSC and TG showed the low melting temperature characteristic of nano-silver and decomposition of organic compounds made the surface resistance of silver film sharply decrease in the sintering process.