Flow-induced non-equilibrium conditions yielded high-purity Dy precipitate from aqueous mixtures of NdCl ₃ and DyCl ₃ more quickly compared to conventional equilibrium stirred mixing.

Seawater electrodeposition is gaining renewed interest in the context of sustainable development, both to build climate-resilient coastal infrastructure and for ocean-based decarbonization applications. Most of the applications benefit from CaCO₃-rich deposits, but constant-voltage electrodeposition results in a mixture of CaCO₃ and Mg(OH)₂, especially at higher voltages where precipitation rates are more desirable. The use of pulse voltages can help control interfacial pH that dictates the precipitation reactions. Here, we explore the use of pulse electrodeposition as a function of pulse frequency and duty cycle to control deposit composition. The most CaCO₃-rich deposits were obtained under 10 Hz frequency and 10% duty cycle conditions for the voltage window investigated (−0.8 V to −1.2 V vs. SCE). While pulsing the voltage increases the amount of CaCO₃ deposited, the energy required per gram of CaCO₃ is significantly higher (14.5×) when compared to the base case of applying a constant voltage of −0.8 V vs. SCE. Further optimization of pulse conditions, electrode materials, and system configuration could lead to finding parameters that result in exclusively carbonate deposits without compromising precipitation rates, which may prove to be more useful for corrosion protection, coastal infrastructure, and other applications in sustainable development.