Synthesis of uniform bulk nanoporous palladium with tunable structure
Synthesis of uniform bulk nanoporous palladium with tunable structure
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DOI：
10.1016/j.electacta.2018.07.081
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发表时间：
2018-07
影响因子：
6.6
通讯作者：
S. Shi;J. Markmann;J. Weissmüller
中科院分区：
文献类型：
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作者：
S. Shi;J. Markmann;J. Weissmüller
本文系统地研究了在硫酸溶液中通过电化学脱合金法制备多级纳米多孔钯。探讨了电极电位、去合金化温度和附加退火对显微组织和形貌的影响。Cu85Pd15在1M硫酸中在高温下脱合金提供了一种简单的策略，以产生均匀的，分级的纳米多孔的，并且没有宏观尺度的裂纹的大块纳米多孔Pd样品。问题“为什么一步无模板去合金化会产生分层而不是单峰的纳米多孔结构？”讨论了钝化和一个purifating富铜集群上的孔结构的影响进行检查。稀释母合金的去合金化的结构不稳定性概念优选作为基本机制。纳米多孔钯与经典的，单峰孔结构和可调的韧带尺寸范围从80至270 nm出现时，所制备的分级纳米多孔钯退火。本研究的材料可以提供一个模型系统，补充纳米多孔Au的大块纳米金属网络作为功能和结构材料的研究。
This work presents systematic investigations on the synthesis of hierarchical nanoporous Pd via electrochemical dealloying of CuPd alloys in sulfuric acid. The impact of electrode potential, dealloying temperature, and additional annealing on microstructure and morphology is explored. Dealloying Cu85Pd15in 1M sulfuric acid at elevated temperature provides a facile strategy to produce bulk nanoporous Pd samples which are uniform, hierarchically nanoporous, and free of macro-scale cracks. The question “Why will one-step template-free dealloying yield a hierarchical and not unimodal nanoporous structure?” is discussed. The impact of passivation and of a percolating Cu-rich cluster on the pore structure is inspected. A structural instability concept for dealloying of dilute master alloys is preferred as the underlying mechanism. Nanoporous Pd with classical, unimodal pore structure and tunable ligament size ranging from 80 to 270 nm emerges when the as-prepared hierarchical nanoporous Pd is annealed. The material of this study may provide a model system that complements nanoporous Au for studies of bulk nanoscale metal networks as functional and structural materials.