Progress in transient electronics depends largely on the availability of components and materials that can decompose in aqueous solutions. However, some of the most important electrically conductive materials, such as copper or aluminum, do not fall into this category. Here, we report a concept for solving this problem based on the preparation of a new water-soluble polymer composite as a packaging material that, when dissolved, releases a chemical etchant that decomposes these two metals. We investigate the synthesis, chemical properties, and solubility kinetics of a polyvinyl alcohol-iron chloride (PVA-FeCl3) composite, its degradation properties, and the associated dissolution mechanisms of metallic Al and Cu films and traces. The results show that Cu films dissolve in a rapid and uniform fashion and produce copper(i) chloride as the end product, while Al films exhibit inconsistent dissolution behavior. Moreover, the timescale for complete dissolution of Cu and Al can be adjusted by simply varying the amount of FeCl3 in the composite. The distinct advantages of this triggered transience mode include low cost, simplicity, precise control of the dissolution process by varying the polymer composition, and a universal degradation mechanism that can be extended to numerous transient electronic devices.
Bibliographical noteFunding Information:
The authors acknowledge ETH Zurich for financial support (ETH Research Grant ETH-45-18-1) and the Young Researcher Exchange Programme-National Research Foundation of Korea for sponsoring the 3 month research exchange in South Korea. This work was supported by Korea University grant, KU-KIST Graduate School of Converging Science and Technology Program, National Research Foundation of Korea (NRF) grant funded by the Korea government (the Ministry of Science, ICT, MSIT) (RS-2022-00165524), and the Ministry of the Science and ICT (MSIT), under the ICT Creative Consilience program (IITP-2023-2020-0-01819) supervised by the IITP (Institute for Information & communications Technology Planning & evaluation). The author would like to thank Dr WonBae Han for many helpful discussions.
© 2023 The Royal Society of Chemistry.
ASJC Scopus subject areas
- General Chemistry
- Renewable Energy, Sustainability and the Environment
- General Materials Science