Jarulertwathana, Nutpaphat Lee, Kyuwon Shin, Hyeseung Ryu, Eui-Jung Kim, In Soo Moon, Cheon Woo Hyun, Jerome K. 2024-10-26T06:30:18Z 2024-10-26T06:30:18Z 2024-10-25 2024-10 2380-8195 https://pubs.kist.re.kr/handle/201004/150854 Metal electrodeposition and dissolution on a transparent electrode enable dynamic switching between the opaque and transparent states, respectively. To be used as dynamic windows, a fully black state must be achieved while maintaining reversibility. Cu is a top candidate that meets the latter criterion but fails the former, producing its characteristic orange tint. As a result, metal additives are often mixed with Cu ions but at the expense of some degree of reversibility. Here, a truly black state is achieved without metal additives by enhancing the dissipative interaction between light and Cu. A galvanic etching method is used to transform a flat ITO surface into an array of nanopillars, forming a gradually varying index across the ITO interface. This elongates the light absorption path length over all wavelengths once Cu is electrodeposited. The electrode is demonstrated in dynamically tunable devices including one that transitions between mirror-like and opaque states with a coloration efficiency of 20.3 cm2 C-1. These results highlight the potential of our strategy in light management devices, particularly for energy-conserving dynamic windows. English American Chemical Society A Black State from Reversible Copper Electrodeposition without Metal Additives Article 10.1021/acsenergylett.4c01976 1 ACS Energy Letters, v.9, no.10, pp.5207 - 5214 ACS Energy Letters 9 10 5207 5214 N scie scopus 001327112300001 2-s2.0-85205738778 Chemistry, Physical Electrochemistry Energy & Fuels Nanoscience & Nanotechnology Materials Science, Multidisciplinary Chemistry Electrochemistry Energy & Fuels Science & Technology - Other Topics Materials Science Article OXIDE DEVICE ITO TRANSPARENT WINDOWS MIRROR BLUE