Reversible Electrodeposition of Ni and Cu for Dynamic Windows

Reversible metal electrodeposition is a promising method for constructing dynamic windows with electronically switchable transparency. Through the reduction of lighting, heating, and cooling costs, these windows reduce energy consumption. Here, we design new electrolytes for reversible metal electrodeposition on tin-doped indium oxide electrodes based on the co-electrodeposition of Ni and Cu. We determined that synergistic effects between Ni and Cu facilitate spectroelectrochemical reversibility in contrast to the individual electrodeposition of these metals. The most reversible electrolytes contain chloride to improve electrodeposition kinetics and sulfamate ions to prevent the formation of dendrites. In addition to improving the color neutrality of the electrodeposits, nickel sulfamate in the electrolytes serves as a source of sulfamate ions that is soluble without added acid. After investigating the functions of the different electrolyte components, we then evaluated the performance of 25 cm 2 two-electrode Ni-Cu dynamic windows.