Preparation of Nanostructured Microporous Metal Foams through Flow Induced Electroless Deposition

Figure 7

Development of hierarchic pore structure during heat treatment of the Ni-P metal deposits. Sample characteristics: [Ni] = 0.13 M; [P] = 1.26 M. Amount of deposition solution used was 600 mL. (a) First stage of the formation of grain surface skin after temperature reached °C during heating at °C/min; . (scale bar = 1 μm). (b) Skin formation after temperature reaches °C during heating at °C/min; . (scale bar = 1 μm). (c) Skin formation after temperature reaches °C during heating at °C/min;  min (scale bar = 2 μm). (d) Full grain skin formation after heat treatment at °C when °C/min;  min followed by cooling in the closed oven until reaching room temperature over a period of 12 hours (scale bar = 2 μm). (e) Details of the skin at high magnification (sample as in Figure 7(d)) showing the existence of the pores with size ca. 200 nm (scale bar = 1 μm). (f) The inner structure of the grains revealed by the fractured grains showing a porous skin and a dense inner core. Sample same as in Figure 7(d) (scale bar = 10 μm).

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