New examples of electrodeposited alloy systems with pattern formation

Abstract

The experience in the pattern formation during electrodeposition of alloys is summarized. The possibility of formation of spatio-temporal structures due to the spontaneous co-deposition of different phases and their self-organization in ordered structures is demonstrated in some new not investigated in this aspect alloy systems, like Cu-Sb, Ag-Sn, Pd-In and Au-In.

Depth-Dependent Scanning Photoelectron Microspectroscopy Unravels the Mechanism of Dynamic Pattern Formation in Alloy Electrodeposition

“…Before starting the SPEM characterization applying Ar sputtering cycles, the pristine structure of the sample was characterized by OM (Figure 1A) and SEM (Figure 2). Previous relevant studies 3,5,38 have already shown the formation of spatial structures during alloy electrodeposition. These structures can be imaged accurately by OM, but exhibit a surprisingly poor contrast in SEM, confirmed by the present study as well.…”

“…Notwithstanding the relatively vast literature on electrochemical pattern formation, the general problem of correlating the electrodeposited patterns with specific alloy chemistry and plating conditions, as well as issues regarding sensitivity, reproducibility and scalability, have not been faced systematically yet. Recent reviews of experimental results , and parametric mathematical modeling (see section S5 of the Supporting Information) have paved the way of this prospective investigation. In any case, spatial patterns in electrodeposited alloys have recently been shown to correlate with a two-phase structure including an intermetallic (see Bozzini et al and references therein).…”

“…For more than half a century, the formation of spatiotemporal structures during alloy electrodeposition has been extensively studied experimentally, starting from Raub’s pioneering paper published in 1938, and recently it has been modeled mathematically in terms of dynamic-system theory (see section S5 of the Supporting Information). Notwithstanding the large corpus of systems investigated, recently reviewed in Bozzini et al and Krastev et al, still the mechanisms governing the spatiotemporal organization during electrochemical phase formation are poorly understood. Electrodeposition studies (for a comprehensive list of references, see Bozzini et al) have initially dealt with a range of Ag alloys (Ag–Sb, Ag–Sn, Ag–In, Ag–Bi, Ag–Cd), but it has been recently shown that similar phenomena also occur with Bi, In and Sb alloys not involving Ag: Ni–P–W–Bi, Au–In, Co–In, , Pd–In, Cu–Sb .…”