Electrochemical Deposition of Co−Sb Thin Films and Nanowires

Abstract

Co-Sb thin films and nanowires were grown on gold-coated polymer templates by electrochemical deposition under different potentiostatic conditions from -0.8 to -1.0 V vs Ag/AgCl. The growth of nanowires was 3D and went through several growth stages starting from the gold-coated wall. Overgrowth of nanowires out of the porous template did not produce a fully dense film; instead, Sb-rich columnar structures (mushroom caps) were developed and connected by Co-rich needle-like structures. Compared to nanowires, the mushroom caps had a lower content of Co. With a more negative deposition potential, the content of Co in the nanowires and the mushroom caps increased. A composition of Co:Sb ) 1:3 in nanowires was obtained at a constant deposition potential of -0.965 V.

Electrodeposition of Ni and Te‐doped Cobalt Triantimonide in Citrate Solutions

“…These are not the final page numbers! ÞÞ Figure 4 shows that although the position of Au oxidation peaks for the initial surface indicates a polycrystalline Au surface with no defined oxidation peaks, the peak around 1.3 V becomes predominant, shifts to about 1.2 V, and becomes sharper during the electrochemical treatment The configuration of the Au oxidation curve points to a potential-dependent rearrangement of the Au atoms in the surface during the electrochemical annealing, which is due to high surface diffusion of Au atoms under the applied potential [24][25]26]. During the electrochemical treatment, the Au surface atoms rearrange themselves by surface diffusion, and this process results in improved surface quality and experimental reproducibility.…”

“…Figure 7 shows a typical plot of the current recorded during the deposition performed at a given potential within À0.55 and À1.2 V, and the current recorded during the stripping performed at 0.4 V i.e. the potential where stripping of the entire deposit is concluded [24]. In Figure 7, a negative current indicates a reduction (deposition) process at the working electrode while a positive value means oxidation (stripping).…”

“…overgrown nanowires).The film is relatively uniform and deposits on the entire membrane surface (Figure 11a), including the pores. Local variations in morphology may be associated with the particular nature of the nanostructured Au surface and hydrogen evolution [24]. Figure 11b shows a typical nanowire array grown in a template.…”

“…Figure 11b shows a typical nanowire array grown in a template. Generally, the formation of nanowires inside a template takes place by means of a nucleation and growth process in several steps [24]. The first process corresponds to a nucleation and growth of the nuclei inside the pores.…”

“…Cheng et al [20] obtained Co-Sb thin films on stainless steel substrates using citric-based solutions. Previous work also reported the growth of Co-Sb nanorods in citrate solution using polycarbonate track-etched (PCTE) templates [21]. Behnke et al [22] investigated the post-deposition annealing treatment of Co-Sb nanowires to form CoSb 3 and reported certain difficulties in obtaining a good stoichiometry due to the antimony loss during heat treatment.…”