Fabrication of porous bismuth by electrochemical dealloying of Sn-Bi alloys: From microporous structures to nanowire matrix composites

- Three-dimensional porous bismuth is fabricated by dealloying Sn-Bi alloys.
- The resulting Bi microstructures are affected by the amount of Bi in the Sn-Bi alloys.
- Single-crystal Bi nanowires growing in the [110] direction are fabricated by dealloying Sn-Bi alloys with a low Bi content.

The fabrication of three-dimensional (3D) porous bismuth by electrochemical dealloying of two-phase Sn-Bi alloys was investigated. The results show that the resulting porous bismuth changes from a microporous structure composed of bismuth microparticles to an aligned nanowire matrix composite as the Bi content in the Sn-Bi master alloy decreases. Single-crystal bismuth nanowires growing in the [110] direction were fabricated by the selective dissolution of the Sn phase from an alloy with ultralow Bi content. The influence of the two states of elemental Bi existing in smelted Sn-Bi alloys during dealloying was systematically analyzed and discussed. This report presents a novel strategy for direct fabrication of bismuth nanowires by electrochemical dealloying.

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