Hydrogen evolution reaction (HER) was intensified to produce bubbles as dynamic templates for the preparation of foamed porous copper (FPCu) in acidic cupric electrolyte. The macroscopic morphologies of FPCu, including pore size distribution and pore density, were determined by the bubble diameter. Bubble assemble behavior was the most important in overall process of gas evolution. Growth of hydrogen bubbles caused coalescence of bubbles and resulted in size increment of the templates. Furthermore, bubble behavior was in tight relation with residence time and current density. Results showed that the morphologies were dependent on deposition time and current density. Small pores in FPCu were attributed to the un-coalesced bubbles and large pores were ascribed to the coalesced bubbles. The embedding and nesting of small holes by the large ones contributed to the formation of hierarchical porous framework. A “stack up layers” model was proposed to illuminate the morphological transformation of FPCu from two-dimensional structure to 3-dimensional framework. Understanding of this model facilitated the preparation of macroporous copper with favorable morphologies.

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An investigation into the ignitions and combustions of porous silicon (PS) nanoenergetic material array chips (nECs) at different ignition voltages was performed. The PS nECs were fabricated by integrating PS nanoenergetic material (nEMs) matrices and Cr-microbridges (microigniters) on the surface of silicon substrates. The combustion of PS nECs was in ambient air. Its ignition and combustion were investigated by a testing system and an optical high-speed camera. Experimental results revealed that the combustion delay time of PS nEMs increased from 8.0 × 10(-5) s to 1.1 × 10(-4) s with the decrement of ignition voltages from 140 to 80 V. The scope of ignition energy ranged from 0.153 to 0.287 mJ by calculations. The reaction type was deflagration, from the analysis of the high-speed video of PS nECs. The comprehensive experimental results indicated that the combustion of PS nECs was ignited by the synergic effect of the heat and the plasma. The ignition experiments suggested that Cr-microbridges were reliable igniters to trigger the self-sustained combustion of PS nECs. The strong plume of flame emitted from the surface of PS nECs indicated that the PS nECs may be applied as micro/nano igniter chips and microthruster chips.

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摘要：采用胶晶模板法制备出具有三维多孔结构的纳米 CoFe2O4。利用 X 射线衍射仪(XRD)、傅里叶变换红 外(FT-IR)光谱仪、扫描电镜(SEM)、透射电镜(TEM)和 N2吸附-脱附对样品的晶型和形貌结构等进行表征， 采用差示扫描量热法(DSC)对比研究多孔纳米 CoFe2O4和球形纳米 CoFe2O4对高氯酸铵(AP)的热分解性能的 影响，并考察这两种催化剂对 AP 催化热分解的动力学参数。结果显示，制备出的多孔纳米 CoFe2O4样品具 有典型的尖晶石结构，孔径约 200 nm；比表面积明显高于 40 nm 球形 CoFe2O4，达到 55.646 m 2 •g -1 。DSC 测试结果表明：多孔纳米 CoFe2O4的加入促进了 AP 的热分解，最高使 AP 的高温分解峰温降低 91.46°C，能