Preparation of a Nickel Layer with Bell-Mouthed Macropores via the Dual-Template Method

Abstract

A relatively static and unique bubble template is successfully realized on a microporous substrate by controlling the surface tensions of the electrodeposit solution, and a nickel layer containing macropores is prepared using this bubble template. When the surface tension of the solution is 50.2 mN/m, the desired bubble template can be formed, there are fewer bubbles attached to other areas on the substrate, and a good nickel layer is obtained. In the analysis of the macropore formation process, it is found that the size of the bell-mouthed macropores can be tailored by changing the solution stirring speed or the current density to adjust the growth rate of the bubble template. The size change of a macropore is measured by the profile angle of the longitudinal macropore, section. As the solution stirring speed increases from 160 to 480 r/min, the angle range of the bell-mouthed macropores cross-sectional profile is increased from 21.0° to 44.3°. In addition, the angle range of the bell-mouthed macropore cross-sectional profile is increased from 39.3° to 46.3° with the current density increasing from 1 to 2.5 A/dm2. Different from the dynamic hydrogen bubble template, the bubble template implemented in this paper stays attached on the deposition and grows slowly, which is novel and interesting, and the nickel layer containing macropores prepared using this bubble template is applied in completely different fields.