A prototype smartwatch made with zinc-silver nanocomposite circuits inside a poly(vinyl alcohol) case (top) dissolves in water within 40 hours (bottom).
Credit: Adapted from ACS Applied Materials & Interfaces 2021, DOI: 10.1021/acsami.1c07102
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) — a polymer that degrades in water — 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.
Original Article: A dissolvable smartwatch makes for easier electronics recycling
More from: Tianjin University | American Chemical Society
The Latest Updates from Bing News & Google News
Go deeper with Bing News on:
Small electronics recycling
- Reworld and Goodwill Keystone Area Introduce Free Electronic Waste Recycling in 22 Central and Southeastern Pennsylvania Counties
Jessica Shirley, Acting Secretary of the state Department of Environmental Protection, was present at the launch event, underscoring the importance of this pivotal move toward enhancing e-waste ...
- More Than Half Of Kiwi Small Businesses Haven’t Recycled E-waste In The Last Year
Over half (61%) of Kiwi businesses admit they haven’t properly disposed of electronic waste (e-waste) in the last year. When asked why they didn’t recycle or dispose of their e-waste, 45% of business ...
- Papio NRD hosting free e-waste collections
The Papio-Missouri River Natural Resources District and Nebraska Loess Hills RC&D Council are hosting free electronic waste recycling collections during May ...
- Goodwill Keystone Area introduce free electronic recycling in 22 counties
Goodwill Keystone Area is offering a new way to get rid of unwanted electronics at no cost to Pennsylvanians. LEMOYNE, Pa. — Goodwill Keystone Area is saying goodbye to unwanted tech after announcing ...
- Goodwill to offer free electronic waste recycling in region
Goodwill Keystone Area and Reworld on Tuesday unveiled a new initiative that will provide free electronic waste recycling in 22 central and southeastern Pennsylvania counties.
Go deeper with Google Headlines on:
Small electronics recycling
[google_news title=”” keyword=”small electronics recycling” num_posts=”5″ blurb_length=”0″ show_thumb=”left”]
Go deeper with Bing News on:
Electronics recycling
- Reworld and Goodwill Keystone Area Introduce Free Electronic Waste Recycling in 22 Central and Southeastern Pennsylvania Counties
Jessica Shirley, Acting Secretary of the state Department of Environmental Protection, was present at the launch event, underscoring the importance of this pivotal move toward enhancing e-waste ...
- Goodwill Debuts Free E-Waste Recycling in 42 Pennsylvania Locations
Goodwill Keystone Area has partnered with Reworld to offer no-cost electronics recycling at its 42 stores located across 22 Pennsylvania counties.
- Electronics recycling event to be held at Calhoun County admin building
Recycling of most things is important, and that extends to old electronic equipment. However, some electronics contain chemicals that require special handling.
- Over 45 tons of old electronics recycled as fundraiser for Wayne County YMCA
Over 45 tons of old electronics were collected for recycling last month at the Wayne County Fairgrounds in a fundraiser for the Wayne County YMCA.
- Reworld™ and Goodwill Keystone Area Introduce Free Electronic Waste Recycling in 22 Central and Southeastern Pennsylvania Counties
Reworld™, in partnership with Goodwill Keystone Area, unveiled a new initiative to provide free electronic waste recycling across 22 central and ...
Go deeper with Google Headlines on:
Electronics recycling
[google_news title=”” keyword=”electronics recycling” num_posts=”5″ blurb_length=”0″ show_thumb=”left”]