2楼: Originally posted by zyhou at 2016-08-04 10:53:19
也许是微量控制交换量，防止金属颗粒长大。
但是，你举的这个例子中，NH4+可能不是竞争交换剂，是缓冲溶液吧，防止Pt(NH3)4++沉淀！

3楼: Originally posted by yan_wei at 2016-08-04 11:05:29
All the catalysts contained 1 wt.% platinum, introduced into the zeolite through ion exchange by 2+ in competition with NH4+ (NH4+/2+ = 100), followed by calcination under dry air flow at 450 8C for ...

3楼: Originally posted by yan_wei at 2016-08-04 11:05:29
All the catalysts contained 1 wt.% platinum, introduced into the zeolite through ion exchange by 2+ in competition with NH4+ (NH4+/2+ = 100), followed by calcination under dry air flow at 450 8C for ...