Stretchable multi-functional fiber for energy harvesting and strain sensing

January 31, 2019, The Korea Advanced Institute of Science and Technology (KAIST)
Stretchable multi-functional fiber for energy harvesting and strain sensing
Figure 1.Schematic illustration of an SMF fiber and its piezoelectric voltage output and response to strain. Credit: The Korea Advanced Institute of Science and Technology (KAIST)

Fiber-based electronics are expected to play a vital role in next-generation wearable electronics. Woven into textiles, they can provide higher durability, comfort, and integrated multi-functionality. A KAIST team has developed a stretchable multi-functional fiber (SMF) that can harvest energy and detect strain, which can be applied to future wearable electronics.

With wearable electronics, health and can be assessed by analyzing biological signals from the human body, such as pulse and muscle movements. Fibers are highly suitable for future wearable electronics because they can be easily integrated into textiles, which are designed to be conformable to curvilinear surfaces and comfortable to wear. Moreover, their weave structures offer support that makes them resistant to fatigue. Many research groups have developed fiber-based strain sensors to sense external biological signals. However, their sensitivities were relatively low.

The applicability of wearable devices is currently limited by their power source, as the size, weight, and lifetime of the battery lessens their versatility. Harvesting from the is a promising solution to overcome such limitations by utilizing various types of motions like bending, stretching, and pressing. However, previously reported, fiber-based energy harvesters were not stretchable and could not fully harvest the available mechanical energy.

Professor Seungbum Hong and Professor Steve Park from the Department of Materials Science and Engineering and their team fabricated a stretchable fiber by using a ferroelectric layer composed of P(VDF-TrFE)/PDMS sandwiched between stretchable electrodes composed of a composite of multi-walled carbon nanotubes (MWCNT) and poly 3,4-ethylenedioxythiophene polystyrenesulfonate (PEDOT:PSS).

Stretchable multi-functional fiber for energy harvesting and strain sensing
Figure 2. Photographs of a stretchable multi-functional fiber being stretched by 100%, bent, and twisted. Credit: The Korea Advanced Institute of Science and Technology (KAIST)

Cracks formed in MWCNT/PEDOT:PSS layer help the fiber show high sensitivity compared to the previously reported fiber strain sensors. Furthermore, the new fiber can harvest mechanical under various mechanical stimuli such as stretching, tapping, and injecting water into the fiber using the piezoelectric effect of the P(VDF-TrFE)/PDMS layer.

Professor Hong said, "This new fiber has various functionalities and makes the device simple and compact. It is a core technology for developing wearable devices with and strain sensing capabilities."

Explore further: Lab team develops hyper-stretchable elastic-composite energy harvester

More information: Jeongjae Ryu et al. Intrinsically stretchable multi-functional fiber with energy harvesting and strain sensing capability, Nano Energy (2018). DOI: 10.1016/j.nanoen.2018.10.071

Related Stories

Researchers develop highly stretchable aqueous batteries

January 26, 2018

The current development of stretchable battery materials that mimic the functions of nature has emerged for the next wave of wearable electronics. A recent study presented a bioinspired Jabuticaba-like hybrid carbon/polymer ...

Fiber OLEDs thinner than a hair

January 10, 2018

Professor Kyung Cheol Choi from the School of Electrical Engineering and his team have fabricated highly efficient organic light-emitting diodes (OLEDs) on an ultra-thin fiber. The team expects the technology, which produces ...

Recommended for you

What rising seas mean for local economies

February 15, 2019

Impacts from climate change are not always easy to see. But for many local businesses in coastal communities across the United States, the evidence is right outside their doors—or in their parking lots.

Where is the universe hiding its missing mass?

February 15, 2019

Astronomers have spent decades looking for something that sounds like it would be hard to miss: about a third of the "normal" matter in the Universe. New results from NASA's Chandra X-ray Observatory may have helped them ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.