FOR IMMEDIATE RELEASE
ACS News Service Weekly PressPac: August 04, 2021
A dissolvable smartwatch makes for easier electronics recyclingÂ
ACS Applied Materials & Interfaces
Small electronics, including smartwatches and fitness trackers, aren’t easily dismantled and recycled. So when a new model comes out, most users send the old devices into hazardous waste streams. To simplify small electronics recycling, researchers reporting in ACS Applied Materials & Interfaces have developed a two-metal nanocomposite for circuits that disintegrates when submerged in water. They demonstrated the circuits in a prototype transient device � a functional smartwatch that dissolved within 40 hours.
Planned obsolescence and the fast pace of technology innovations leads to new devices that are continuously replacing old versions, which generates millions of tons of electronic waste per year. Recycling can reduce the volume of e-waste and is mandatory in many places. However, it often isn’t worth the effort to recycle small consumer electronics because their parts must be salvaged by hand, and some processing steps, such as open burning and acid leaching, can cause health issues and environmental pollution. Dissolvable devices that break apart on demand could solve both of those problems. Previously Xian Huang and colleagues developed a zinc-based nanocomposite that dissolved in water for use in temporary circuits, but it wasn’t conductive enough for consumer electronics. So, they wanted to improve their dissolvable nanocomposite’s electrical properties while also creating circuits robust enough to withstand everyday use.
The researchers modified the zinc-based nanocomposite by adding silver nanowires, making it highly conductive. Then, they screen-printed the metallic solution onto pieces of poly(vinyl alcohol) â€� a polymer that degrades in water â€� and solidified the circuits by applying small droplets of water that facilitate chemical reactions and then evaporate. With this approach, the team made a smartwatch with multiple nanocomposite-printed circuit boards inside a 3D printed poly(vinyl alcohol) case. The smartwatch had sensors that accurately measured a person’s heart rate, blood oxygen levels and step count, and sent the information to a cellphone app via a Bluetooth connection. The outer package held up to sweat, but once the whole device was fully immersed in water, both the polymer case and circuits dissolved completely within 40 hours. All that was left behind were the watch’s components, such as an organic light-emitting diode (OLED) screen and microcontroller, as well as resistors and capacitors that had been integrated into the circuits. The researchers say the two-metal nanocomposite can be used to produce transient devices with performance matching that of commercial models, which could go a long way toward solving the challenges of small electronics waste.Â
The authors do not acknowledge a funding source for this study.
###
The American Chemical Öйú365betÖÐÎĹÙÍø (ACS) is a nonprofit organization founded in 1876 and chartered by the U.S. Congress. ACS is committed to improving all lives through the transforming power of chemistry. Its mission is to advance scientific knowledge, empower a global community and champion scientific integrity, and its vision is a world built on science. The Öйú365betÖÐÎĹÙÍø is a global leader in promoting excellence in science education and providing access to chemistry-related information and research through its multiple research solutions, peer-reviewed journals, scientific conferences, e-books and weekly news periodical Chemical & Engineering News. ACS journals are among the most cited, most trusted and most read within the scientific literature; however, ACS itself does not conduct chemical research. As a leader in scientific information solutions, its CAS division partners with global innovators to accelerate breakthroughs by curating, connecting and analyzing the world’s scientific knowledge. ACSâ€� main offices are in Washington, D.C., and Columbus, Ohio.
Registered journalists can subscribe to the to access embargoed and public science press releases. For media inquiries, contact newsroom@acs.org.
Note: ACS does not conduct research but publishes and publicizes peer-reviewed scientific studies.
Media Contact
ACS Newsroom
newsroom@acs.org
###
La sociedad American Chemical Öйú365betÖÐÎĹÙÍø (ACS) es una organización sin fines de lucro fundada en 1876 y aprobada por el Congreso de los Estados Unidos. La ACS se ha comprometido a mejorar la vida de todas las personas mediante la transformación del poder de la quÃmica. Su misión es promover el conocimiento cientÃfico, empoderar a la comunidad global y defender la integridad cientÃfica, y su visión es un mundo construido basándose en la ciencia. La Sociedad es lÃder mundial en la promoción de la excelencia en la educación cientÃfica y en el acceso a información e investigación relacionadas con la quÃmica a través de sus múltiples soluciones de investigación, publicaciones revisadas por expertos, conferencias cientÃficas, libros electrónicos y noticias semanales periódicas de Chemical & Engineering News. Las revistas de la ACS se encuentran entre las más citadas, las más fiables y las más leÃdas en la literatura cientÃfica; sin embargo, la propia ACS no realiza investigación quÃmica. Como lÃder en soluciones de información cientÃfica, su división CAS se asocia con innovadores internacionales para acelerar los avances mediante la preservación, la conexión y el análisis de los conocimientos cientÃficos del mundo. Las sedes principales de la ACS se encuentran en Washington, D.C., y Columbus, Ohio.
Los periodistas registrados pueden suscribirse al en EurekAlert! para acceder a comunicados de prensa públicos y retenidos. Para consultas de los medios, comunÃquese con newsroom@acs.org.
Nota: ACS no realiza investigaciones, pero publica y divulga estudios cientÃficos revisados por expertos.â€�
View the image