Nonaqueous electrolytes for reversible zinc electrodeposition for dynamic windows with excellent optical contrast and durability

Summary

In this study, we design high-performing dynamic windows based on the reversible electrodeposition of Zn from nonaqueous electrolytes containing dimethyl sulfoxide (DMSO). We develop Zn-DMSO electrolytes that support electrochemically and optically reversible Zn electrodeposition with high optical contrast (∼75% clear-state transmission and <0.1% dark-state transmission). The optoelectronic reversibility of the Zn electrodeposition enables devices to cycle thousands of times without degradation in optical contrast. The electrolytes facilitate the formation of a compact Zn electrodeposit morphology that blocks light efficiently, which reduces the current needed and thereby aids in device scale-up due to a minimal voltage drop across the transparent conducting electrode. Devices with a transparent Zn mesh as the counter electrode switch uniformly at the 100-cm² scale. Lastly, the noncorrosive nature of the Zn electrolytes results in the formation of devices that possess long-term shelf lives and dark-state stability in the absence of applied power.