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Alloy-based materials such as antimony (Sb) are of interest for both Li/Na-ion batteries due to their high theoretical capacity and electronic conductivity. Of the various ways to fabricate Sb films (slurry casting, sputtering, etc.) one promising route is through electrodeposition. Electrodeposition is an industrially relevant synthetic technique that allows for the use of solution additives to control different characteristics such as film uniformity, morphology, and electrical conductivity. Solution additives such as cetyltrimethylammonium bromide (CTAB) and bis(3-sulfopropyl) disulfide (SPS) have been used to control different characteristics such as particle morphology and electrical conductivity in various electrodeposits but have not been applied to the electrodeposition of Sb for battery applications. In this study, Sb films were electrodeposited with varied concentrations of CTAB and SPS and the structure, morphology, composition, and electrochemical performance in Na-ion batteries were compared. We report that CTAB and SPS additives can significantly influence electrodeposited Sb films by altering the morphology and reduce the crystallinity, affecting the electrochemical performance. These studies provide valuable insight into the tunability of alloy-based films through electrodeposition and solution additives for battery applications. 

Electrodeposited Cu–Sb thin films on Cu and Ni substrates are investigated as alloy anodes for Li-ion batteries to elucidate the effects of both the film composition and substrate interactions on anode cycling stability and lifetime. Thin films of composition Cu x Sb (0 < x < 2) exhibit the longest cycle lifetimes nearest x = 1. Additionally, the Cu–Sb films exhibit shorter cycle lifetimes when electrodeposited onto Cu substrates when compared to equivalent films on Ni substrates. Ex situ characterization and differential capacity analysis of the anodes reveal that significant interdiffusion occurs during cycling between pure Sb films and Cu substrates. The great extent of interdiffusion results in mechanical weakening of the film–substrate interface that exacerbates film delamination and decreases cycle lifetimes of Cu–Sb films on Cu substrates regardless of the film's composition. The results presented here demonstrate that the composition of the anode alone is not the most important predictor of long term cycle stability; the composition coupled with the identity of the substrate is key. These interactions are critical to understand in the design of high capacity, large volume change materials fabricated without the need for additional binders.