Nav: Home

New fiber-shaped supercapacitor for wearable electronics

April 18, 2019

Fiber electrodes, as the key part of fiber-shaped supercapacitors for wearable electronics, are widely explored on the basis of carbon nanomaterials such as carbon nanotubes (CNTs) and graphene fibers due to their high mechanical strength, electrical conductivity and specific surface area. The incorporation of carbon nanomaterials with other pseudocapacitive materials is a common strategy to improve the electrochemical properties of resulting fiber-shaped supercapacitors. However, the pseudocapacitance is far from fully developed especially at high rate owing to the insufficient electron supply and ion accessibility during electrochemical reactions. Hence developing new fiber electrodes is very important to realize efficient electron supply and ion accessibility simultaneously in one single fiber.

Recently, Prof. Huisheng Peng's group from Fudan University, China designed a novel family of amphiphilic core-sheath structured CNT composited fiber, i.e., CNT-gold@hydrophilic CNT-polyaniline (CNT-Au@OCNT-PANI) to meet the above requirements in Science China Materials (DOI: 10.1007/s40843-018-9408-3).

Prof. Peng stated: "The amphiphilic core-sheath structured CNT composited fiber can achieve more ion accessibility across the sheath originating from the enhanced interactions between OCNTs and PANI, and faster electron transport across the core attributing to the sufficient deposition of Au nanoparticles on the CNTs. This electrode design can improve both the electrical conductivity and electrochemical activity of one single fiber electrode."

They systematically studied the morphologies and electrochemical properties of electrodeposited PANI on the hydrophilic OCNT and hydrophobic CNT sheath. More oxygen-containing functional groups and defect sites on hydrophilic OCNT sheath are beneficial to the infiltration and electrodeposition of aniline in the aqueous electrolyte, improving the interactions between OCNTs and PANI than those between CNTs and PANI. As a result, PANI molecules are less aggregated with more accessibility to the ions in the electrolyte during charging and discharging processes, realizing a greater pseudocapacitance utilization. As to the Au-deposited CNT core, the homogeneous distribution of Au nanoparticles facilitates the electron transport among CNTs which finally reduces the internal resistance. Impressively, the CNT-Au@OCNT-PANI demonstrates both high specific capacitance and rate capability, i.e., 256 F cm?3 at a high current density of 50 A cm?3 with a 79% retention of that at 0.5 A cm?3 (324 F cm?3). A remarkable energy density and power density of 7.2 mWh cm?3 and 10 W cm?3 are achieved in the resulting fiber-shaped supercapacitors, respectively.

"Our new concept, increasing the electron supply and ion accessibility simultaneously, can guide the future electrode design aiming at high performances," says Prof. Peng. "And the strategy of structure design and material utilization can be generalized to other energy storage systems including but not limited to lithium-ion and metal-air batteries. We believe this finding will be of interest to readers in energy science, materials chemistry and catalysis."
This work was supported by the Ministry of Science and Technology, the National Natural Science Foundation of China, Shanghai Science and Technology Committee, and Yanchang Petroleum Group.

See the article: Xuemei Fu, Zhuoer Li, Limin Xu, Meng Liao, Hao Sun, Songlin Xie, Xuemei Sun, Bingjie Wang and Huisheng Peng, "Amphiphilic core-sheath structured composite fiber for comprehensively performed supercapacitor", Science China Materials. doi: 10.1007/s40843-018-9408-3

Science China Press

Related Wearable Electronics Articles:

Stretchable supercapacitors to power tomorrow's wearable devices
Researchers have engineered a novel type of supercapacitor that maintains full functionality even when stretched to eight times its original size.
Fish scales could make wearable electronics more sustainable
Flexible temporary electronic displays may one day make it possible to sport a glowing tattoo or check a reading, like that of a stopwatch, directly on the skin.
This wearable device camouflages its wearer no matter the weather
Researchers at the University of California San Diego developed a wearable technology that can hide its wearer from heat-detecting sensors such as night vision goggles, even when the ambient temperature changes -- a feat that current state of the art technology cannot match.
Fur-friendly 'wearable for pets' developed at Imperial
Imperial College London researchers have invented a new health tracking sensor for pets and people that monitors vital signs through fur or clothing.
Improving adhesives for wearable sensors
By conveniently and painlessly collecting data, wearable sensors create many new possibilities for keeping tabs on the body.
Wearable health tech gets efficiency upgrade
North Carolina State University engineers have demonstrated a flexible device that harvests the heat energy from the human body to monitor health.
A new stretchable battery can power wearable electronics
The adoption of wearable electronics has so far been limited by their need to derive power from bulky, rigid batteries that reduce comfort and may present safety hazards due to chemical leakage or combustion.
A wearable gas sensor for health and environmental monitoring
A highly sensitive, wearable gas sensor for environmental and human health monitoring may soon become commercially available, according to researchers at Penn State and Northeastern University.
Skin-like sensors bring a human touch to wearable tech
University of Toronto Engineering researchers have developed a super-stretchy, transparent and self-powering sensor that records the complex sensations of human skin.
Wearable AC
One day, soldiers could cool down on the military battlefield -- preventing heat stroke or exhaustion -- by using 'wearable air conditioning,' an on-skin device designed by engineers at the University of Missouri.
More Wearable Electronics News and Wearable Electronics Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Listen Again: Reinvention
Change is hard, but it's also an opportunity to discover and reimagine what you thought you knew. From our economy, to music, to even ourselves–this hour TED speakers explore the power of reinvention. Guests include OK Go lead singer Damian Kulash Jr., former college gymnastics coach Valorie Kondos Field, Stockton Mayor Michael Tubbs, and entrepreneur Nick Hanauer.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Dispatch 6: Strange Times
Covid has disrupted the most basic routines of our days and nights. But in the middle of a conversation about how to fight the virus, we find a place impervious to the stalled plans and frenetic demands of the outside world. It's a very different kind of front line, where urgent work means moving slow, and time is marked out in tiny pre-planned steps. Then, on a walk through the woods, we consider how the tempo of our lives affects our minds and discover how the beats of biology shape our bodies. This episode was produced with help from Molly Webster and Tracie Hunte. Support Radiolab today at