FABRICATION OF ULTRAFINE NANOPOROUS COPPER STABILIZED BY NOBLE METALS WITH LOW SURFACE DIFFUSIVITY

以Ti-Cu-M （M:Ag, Au, Ni, Pd, Pt）非晶前驱体合金为原料，在HF溶液中合金化制备了超细纳米孔铜（NPC）。M稳定的非晶态纳米材料的孔径小于10 nm，与NP Au、NP Pt的孔径相似。与无M的Ti-Cu非晶态纳米材料相比，纳米材料的孔径减小了约1-2个数量级。M吸附原子的引入抑制了铜吸附原子在合金脱合金过程中的长距离快速自由扩散。M原子缓慢扩散导致表面扩散率急剧下降，表明合金/溶液界面处的扩散控制了NPCs的形成。超细纳米催化剂的应用不仅可以节省成本，而且可以减少对稀有铂资源的消耗，对社会有很大的帮助。

Ultrafine nanoporous copper (NPC) was fabricated from Ti-Cu-M (M:Ag, Au, Ni, Pd, Pt) amorphous precursor alloys by dealloying in HF solutions. NPCs stabilized by M had a pore size less than 10 nm, which is similar with that of NP Au, NP Pt. In comparison to NPCs fabricated from M-free Ti-Cu amorphous precursors, the pore size decreased about 1-2 orders. The introduction of M adatoms resulted in the suppression of the fast long-distance free diffusion of Cu adatoms during dealloying. The drastic decrease in the surface diffusivity caused by the slow diffusion of M adatoms indicated that the diffusion at the interface of alloy/solution controlled the formation of NPCs. The application of the present ultrafine NPCs has a potential to replace the conventional Pt nanoparticle catalysts, which can save the cost and on the other hand, the decrease of the consuming of rare Pt resources will help our society.