14 research outputs found
Transparent and Flexible Triboelectric Sensing Array for Touch Security Applications
Tactile sensors with large-scale
array and high sensitivity is essential for human–machine interaction,
smart wearable devices, and mobile networks. Here, a transparent and
flexible triboelectric sensing array (TSA) with fingertip-sized pixels
is demonstrated by integrating ITO electrodes, FEP film, and signal
transmission circuits on an undivided palm-sized polyethylene terephthalate
substrate. The sensing pixels can be triggered by the corresponding
external contact to induce the electrostatic potential in the transparent
electrodes without power consumption, which is individually recognized
by the sensor. By testing the response of the pixels, the electrical
characterization is systematically investigated. The proposed TSA
exhibits excellent durability, independence, and synchronicity, which
is able to realize real-time touch sensing, spatial mapping, and motion
monitoring. The integrated TSA has great potential for an active tactile
system, human–machine interface, wearable electronics, private
communication, and advanced security identification
Rotating-Sleeve Triboelectric–Electromagnetic Hybrid Nanogenerator for High Efficiency of Harvesting Mechanical Energy
Currently, a triboelectric nanogenerator (TENG) and an electromagnetic
generator (EMG) have been hybridized to effectively scavenge mechanical
energy. However, one critical issue of the hybrid device is the limited
output power due to the mismatched output impedance between the two
generators. In this work, impedance matching between the TENG and
EMG is achieved facilely through commercial transformers, and we put
forward a highly integrated hybrid device. The rotating-sleeve triboelectric–electromagnetic
hybrid nanogenerator (RSHG) is designed by simulating the structure
of a common EMG, which ensures a high efficiency in transferring ambient
mechanical energy into electric power. The RSHG presents an excellent
performance with a short-circuit current of 1 mA and open-circuit
voltage of 48 V at a rotation speed of 250 rpm. Systematic measurements
demonstrate that the hybrid nanogenerator can deliver the largest
output power of 13 mW at a loading resistance of 8 kΩ. Moreover,
it is demonstrated that a wind-driven RSHG can light dozens of light-emitting
diodes and power an electric watch. The distinctive structure and
high output performance promise the practical application of this
rotating-sleeve structured hybrid nanogenerator for large-scale energy
conversion
Lithium-Ion Batteries: Charged by Triboelectric Nanogenerators with Pulsed Output Based on the Enhanced Cycling Stability
The triboelectric
nanogenerator (TENG) has been used to store its generated energy into
lithium-ion batteries (LIBs); however, the influences of its pulse
current and high voltage on LIB polarization and dynamic behaviors
have not been investigated yet. In this paper, it is found that LIBs
based on the phase transition reaction of the lithium storage mechanism
[LiFePO<sub>4</sub> (LFP) and Li<sub>4</sub>Ti<sub>5</sub>O<sub>12</sub> (LTO) electrodes] are more suitable for charging by TENGs. Thus,
the enhanced cycling capacity, Coulombic efficiency (nearly 100% for
LTO electrode), and energy storage efficiency (85.3% for the LFP–LTO
electrode) are successfully achieved. Moreover, the pulse current
has a positive effect on the increase of the Li-ion extraction, reducing
the charge-transfer resistance (<i>R</i><sub>ct</sub>) for
all studied electrodes as well (LFP, LiNi<sub>0.6</sub>Co<sub>0.2</sub>Mn<sub>0.2</sub>O<sub>2</sub>, LTO, and graphite). The excellent
cyclability, high Coulombic, and energy storage efficiencies demonstrated
the availability of storing pulsed energy generated by TENGs. This
research has provided a promising analysis to obtain an enhanced charging
methodology, which provides significant guidance for the scientific
research of the LIBs
All-Nanofiber-Based Ultralight Stretchable Triboelectric Nanogenerator for Self-Powered Wearable Electronics
The
flexible and stretchable electronics have been considered as next-generation
electronics. Stretchable triboelectric nanogenerators (S-TENGs) with
both multifunction and comfort have become a hot field of research
for wearable electronic devices recently. Here, we designed an all-nanofiber-based,
ultralight, S-TENG that could be softly attached on skins for motion
energy harvesting and self-powered biomechanical monitoring. The S-TENG
consisted of only two nanofiber membranes: a polyvinylidene fluoride
nanofiber membrane (PVDFNM) supported by thermoplastic polyurethane
nanofiber membrane (TPUNM) was used as the frictional layer, and a
multiwalled carbon nanotube (MWCNT) conductive material screen-printed
on the TPUNM was used as the electrode layer. Due to the excellent
stretchability of TPUNM, the S-TENG could generate electricity under
various types of deformation, and regains its original performance
after intense mechanical extension, even if it is partially cut or
damaged. Owing to the great electronegativity of PVDFNM, the device
generated a maximum voltage of 225 V and a current of 4.5 ÎĽA
with an electrode area of 6 Ă— 1 cm<sup>2</sup>. The S-TENG has
great potential applications in self-powered wearable devices, electronic
skins, and smart sensor networks
All-Nanofiber-Based Ultralight Stretchable Triboelectric Nanogenerator for Self-Powered Wearable Electronics
The
flexible and stretchable electronics have been considered as next-generation
electronics. Stretchable triboelectric nanogenerators (S-TENGs) with
both multifunction and comfort have become a hot field of research
for wearable electronic devices recently. Here, we designed an all-nanofiber-based,
ultralight, S-TENG that could be softly attached on skins for motion
energy harvesting and self-powered biomechanical monitoring. The S-TENG
consisted of only two nanofiber membranes: a polyvinylidene fluoride
nanofiber membrane (PVDFNM) supported by thermoplastic polyurethane
nanofiber membrane (TPUNM) was used as the frictional layer, and a
multiwalled carbon nanotube (MWCNT) conductive material screen-printed
on the TPUNM was used as the electrode layer. Due to the excellent
stretchability of TPUNM, the S-TENG could generate electricity under
various types of deformation, and regains its original performance
after intense mechanical extension, even if it is partially cut or
damaged. Owing to the great electronegativity of PVDFNM, the device
generated a maximum voltage of 225 V and a current of 4.5 ÎĽA
with an electrode area of 6 Ă— 1 cm<sup>2</sup>. The S-TENG has
great potential applications in self-powered wearable devices, electronic
skins, and smart sensor networks
All-Nanofiber-Based Ultralight Stretchable Triboelectric Nanogenerator for Self-Powered Wearable Electronics
The
flexible and stretchable electronics have been considered as next-generation
electronics. Stretchable triboelectric nanogenerators (S-TENGs) with
both multifunction and comfort have become a hot field of research
for wearable electronic devices recently. Here, we designed an all-nanofiber-based,
ultralight, S-TENG that could be softly attached on skins for motion
energy harvesting and self-powered biomechanical monitoring. The S-TENG
consisted of only two nanofiber membranes: a polyvinylidene fluoride
nanofiber membrane (PVDFNM) supported by thermoplastic polyurethane
nanofiber membrane (TPUNM) was used as the frictional layer, and a
multiwalled carbon nanotube (MWCNT) conductive material screen-printed
on the TPUNM was used as the electrode layer. Due to the excellent
stretchability of TPUNM, the S-TENG could generate electricity under
various types of deformation, and regains its original performance
after intense mechanical extension, even if it is partially cut or
damaged. Owing to the great electronegativity of PVDFNM, the device
generated a maximum voltage of 225 V and a current of 4.5 ÎĽA
with an electrode area of 6 Ă— 1 cm<sup>2</sup>. The S-TENG has
great potential applications in self-powered wearable devices, electronic
skins, and smart sensor networks
Regions showing significantly altered connectivity with the amygdala in females with MDD compared to HC.
<p>Panel A shows significantly altered connectivity with the amygdala in females with MDD compared to HC. Panel B shows the statistical maps rendered on a SurfTemplate by using the BrainNet Viewer (<a href="http://www.nitrc.org/projects/bnv" target="_blank">http://www.nitrc.org/projects/bnv</a>); the magenta dot is the seed–the right amygdala; aquamarine dots indicate the right VLPFC, bilateral insula, bilateral parahippocampus, bilateral putamen, bilateral pallidus, and bilateral thalamus that displayed significantly decreased connectivity with the amygdala in females with MDD relative to HC. In contrast, no significant increased functional connectivity relevant to seed was detected among females with MDD compared to HC. The significance level was set as single voxel threshold of <i>p</i><0.01 and cluster size > 251 voxels, using AlphaSim correction. Panel C shows significant correlations between connectivity and anxiety scores; the upper row displays the connectivity of the left pallidus, relevant to the right amygdala, significantly correlates with anxiety scores (r = 0.52, <i>p</i> = 0.0017); the bottom row displays the connectivity of the left hippocampus, relevant to the right amygdala, significantly correlates with anxiety scores (r = 0.36, <i>p</i> = 0.0314).</p
The locations of regions showing significantly altered GM volume in females with MDD compared to HC.
<p>The locations of regions showing significantly altered GM volume in females with MDD compared to HC.</p
The locations of the regions showing significantly altered connectivity with the amygdala in females with MDD compared to HC.
<p>The locations of the regions showing significantly altered connectivity with the amygdala in females with MDD compared to HC.</p