Electronic Skin for Programmable Touch Operation Platform

Zhao et al., Sci. Adv. 2020; 6 : eaba4294 8 July 2020
SCI ENCE ADVANCES | RESEARCH ARTICLE
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APPLIED SCIENCE AND ENGINEERING
Self-powered user-interactive electronic skin
for programmable touch operation platform
Xuan Zhao1,2
*, Zheng Zhang1,2
*, Qingliang Liao1,2†
, Xiaochen Xun1,2
, Fangfang Gao1,2
,
Liangxu Xu1,2
, Zhuo Kang1,2
, Yue Zhang1,2†
User-interactive electronic skin is capable of spatially mapping touch via electric readout and providing visual
output as a human-readable response. However, the high power consumption, complex structure, and high cost
of user-interactive electronic skin are notable obstacles for practical application. Here, we report a self-powered,
user-interactive electronic skin (SUE-skin), which is simple in structure and low in cost, based on a proposed
triboelectric-optical model. The SUE-skin achieves the conversion of touch stimuli into electrical signal and
instantaneous visible light at trigger pressure threshold as low as 20 kPa, without external power supply. By inte-
grating the SUE-skin with a microcontroller, a programmable touch operation platform was built that can recog-
nize more than 156 interaction logics for easy control of consumer electronics. This cost-effective technology has
potential relevance to gesture control, augmented reality, and intelligent prosthesis applications.
INTRODUCTION
Human-machine interaction (HMI) is implemented by three parts
(human, machine, and interactive medium) whose task is to complete
two processes (instructing the machine and giving feedback to
humans) (1–3). Since most devices are controlled by electrical signals,
the process of giving control commands to the machine generally
relies on electrical readouts, such as using a keyboard and mouse to
operate the computer (4–9). On the basis of the fact that humans
cannot directly obtain information in electrical signals, the process of
giving feedback to human in HMI relies on the human-perceivable
signals such as visible light, sound, and force (10–13). Visible light
is generally considered as the best candidate because of its higher
spatial resolution and intuitiveness, such as using a display screen
(14, 15). However, with the rapid development of wearable devices,
artificial prosthetics, and robotics, the traditional interactive medium
is difficult to meet the needs in terms of flexibility, portability, and
low power consumption (16–20).
As a network of flexible sensors, the electronic skin (e-skin) is
becoming the primary interactive medium for next-generation HMI
due to spatial mapping and amplitude quantifying of touch stimuli.
Early works on e-skin focused on the optimization of pressure sensors
for command delivery and lack of research on human-readable output
(21–27). Until Javey and colleagues (28) integrated thin-film tran-
sistors, pressure sensors, and organic light-emitting diode arrays to
invent a device that provides an instant visual response to pressure,
researchers opened a new era of user-interactive e-skin. After that,
Bao and colleagues (29) reported a stretchable e-skin with inter-
active color-changing and tactile-sensing properties. Shepherd and
colleagues (30) proposed an electroluminescent skin for optical
signaling and tactile sensing. Despite these achievements, the above
devices rely on the external power supply for both tactile sensing
and touch visualization, which brings significant challenges to
portability and integration. Although Wang and colleagues (31)
invented a self-powered optical and electrical dual-mode pressure
sensor based on the triboelectrification and mechanoluminescence,
it requires up to several megapascals of pressure to produce visible
light. Since the pressure threshold of mechanoluminescence is
much higher than the strength of human touch (typically less than
100 kPa), this device cannot be used for user-interactive e-skin.
The present work introduces a self-powered, user-interactive
e-skin (SUE-skin), which can be readily prepared by a cost-effective
processing approach (Fig. 1). The realization of this concept is based
on the proposed triboelectric-optical model. The SUE-skin is capable
of simultaneously converting touch stimuli into electrical signals and
real-time visible lights without relying on the external power supply.
Weexploredaprogrammabletouchoperationplatformforimplement-
ing interactive control of consumer electronics by combining the
microcontroller. Furthermore, benefiting from the above charac-
teristics, the SUE-skin may achieve high-robust touch track mapping
by superimposing of the electrical and optical signals.
RESULTS
Concept and processing approach of the SUE-skin
Here, the SUE-skin, capable of simultaneously generating electrical
and optical signals without external power supply under touch stimuli,
is shown in Fig. 1A. The electrical signals generated when the finger
touches the SUE-skin can be processed by the microcontroller unit
(MCU) as control commands for various consumer electronic
devices, and the optical signals generated can be directly observed
by the human eyes. Figure 1B shows the optical photograph of the
visual output during a sliding touch (movie S1, under dark condi-
tions; fig. S1A and movie S2, under ambient conditions). One frame
is taken every 0.5 s, and a total of seven frames are taken in 3 s. For
comparison, the last picture was obtained by time-lapse photography.
During photography, the exposure time of each frame is 1/10 s.
Figure 1C shows the chromaticity diagram calculated from the
emission spectrum acquired during the touch process, by the GoCIE
software. The color coordinate of the yellow-green light emitted
by the SUE-skin is (0.33, 0.60). Figure 1D shows the stability and
repeatabilitytestoftheSUE-skin’sluminescencefeatureby 1000 cycles.
1
Beijing Advanced Innovation Center for Materials Genome Engineering, Beijing
Key Laboratory for Advanced Energy Materials and Technologies, University of
Science and Technology Beijing, Beijing 100083, China. 2
State Key Laboratory for
Advanced Metals and Materials, School of Materials Science and Engineering,
University of Science and Technology Beijing, Beijing 100083, China.
*These authors contributed equally to this work.
†Corresponding author. Email: liao@ustb.edu.cn (Q.L.); yuezhang@ustb.edu.cn (Y.Z.)
Copyright © 2020
The Authors, some
rights reserved;
exclusive licensee
American Association
for the Advancement
of Science. No claim to
originalU.S. Government
Works. Distributed
under a Creative
Commons Attribution
NonCommercial
License 4.0 (CC BY-NC).
onJuly27,2020http://advances.sciencemag.org/Downloadedfrom

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Figure 1E shows the output voltage of the SUE-skin under sliding
touch stimuli. The schematics for the fabrication procedure of
the SUE-skin, as shown in Fig. 1F [note S1 and fig. S1 (B to D) for
synthesis and characterization of ZnS (ZnS: Cu, Al) phosphor
particles;MaterialsandMethodsfordetailsoftheSUE-skinfabrication].
The as-fabricated SUE-skin consists of a phosphor layer, an electrode
(Al), an insulating layer (Kapton), a shield layer (Al), and a substrate
[polydimethylsiloxane (PDMS)]. The shield is grounded during
operation to minimize external interference during electrical signal
acquisition. Most of the traditional triboelectric-electroluminescent
devices are based on ZnS: Cu (32–35), and the ZnS: Cu, Al synthesized
here has higher luminous efficiency than ZnS: Cu because it is doped
with Al as a co-activator. As shown in fig. S1E, under the same
touch stimuli, the luminous brightness of ZnS: Cu, Al–based SUE-skin
is much higher than that of ZnS: Cu–based SUE-skin. Figure 1G
shows that the SUE-skin can be bent, rolled, and folded without any
mechanical failure, with a minimum bending radius of 2 mm and a
maximum folding pressure of 2 MPa. As shown in fig. S1 (F to K),
the luminous intensities have been recorded every 40 bending/rolling
cycles, and the time-lapse optical photos and surface scanning elec-
tron microscopy (SEM) images of SUE-skin have been taken every
400 bending/rolling cycles. The luminous intensity and surface
topography remain stable during and after 1200 bending/rolling
cycles, which demonstrate that the SUE-skin has excellent mechanical
stability.
The triboelectric-optical model
The SUE-skin’s ability to achieve touch visualization and mapping
at low-pressure thresholds is based on our proposed triboelectric-
optical model, which induces both electrostatic induction and
electroluminescence through triboelectrification, as shown in Fig. 2A
(contact-separation mode) and fig. S2 (sliding mode; note S2). The
charge transfer behaviors of the processes of contact-separation
mode and sliding mode are similar in the basic principle of the
triboelectrification. Here, it is assumed that the dielectric binder has
a larger surface work function than human skin.
When the human skin is in full contact with the SUE-skin
(Fig. 2Ai), the human skin and the dielectric adhesive acquire net
positive and net negative triboelectric charges, respectively. When
the human skin gradually separates from the SUE-skin (Fig. 2Aii),
the top surface of the dielectric adhesive is negatively charged, and
an induced current is generated in the external circuit. During this
process, there is a varying electric field between the top surface of
the dielectric binder and the electrode. The electrons produced within
Fig. 1. Concept and processing approach of the SUE-skin. (A) Schematic diagram of the SUE-skin, which can convert a touch stimulation into an optical signal visible
to the human eye and an electrical signal for machine control simultaneously. IoT, Internet of things. (B) The multiple frames at different timestamps (1 to 7) and the time-
lapse optical photo (8) of the visual output under the sliding touch. (C) The chromaticity diagram calculated from the emission spectrum of SUE-skin. (D) Stability and
repeatability test of the SUE-skin’s luminescence feature by 1000 cycles. (E) The voltage output of the SUE-skin under sliding touch stimuli. (F) Process flow diagram for
device fabrication. (G) The SUE-skin was subjected to different mechanical deformations sequentially, which was (i) original, (ii) bent, (iii) rolled, (iv) folded, and (v)
released. Scale bars, 1 cm. a.u., arbitrary units. Photo credit for (B) and (G): Xuan Zhao, University of Science and Technology Beijing.

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the lattice by the impact ionization move toward the bottom of the
ZnS phosphor particle under the induction of the above varying
electric field (36, 37). During the movement, some of the electrons
affect the luminescence centers, thereby exciting the luminescence
centers and causing electroluminescence. When the human skin is
completely separated (the threshold distance for complete separation
is about 1 to 2 mm) from the SUE-skin (Fig. 2Aiii), no current is
generated in the external circuit. At the same time, the electrons
have been concentrated at the bottom of the ZnS phosphor particle
under the electric field induction and will not affect the luminescence
centers, so the device does not emit light. When the human skin
approaches the SUE-skin again (Fig. 2Aiv), an induced current is
generated again in the external circuit. During this process, the electric
field between the upper surface of the dielectric binder and the elec-
trode gradually disappears. The electrons inside the ZnS that lose
the effect of the electric field move in reverse and impact with the
luminescence centers again to excite it and cause electroluminescence
again. As described in the model, there are two luminescence phe-
nomena in one contact-separation cycle (movie S3). Of course, for
sliding touch, since the time from the start of the contact to the
complete separation is short, and the electroluminescence of ZnS
has an afterglow of tens to hundreds of milliseconds, it is generally
difficult to distinguish the two luminescence phenomena during
the period.
The higher the pressure during the contact-separation process,
the greater the amplitude of the electrical and optical signals generated
by the SUE-skin, as shown in Fig. 2B. However, if a prestress is
applied in advance under the contact state, and then adding stress is
added to the prestress so that the final pressure is equal to 300 kPa,
as shown in Fig. 2C, then the amplitude of the output electrical and
optical signals decreases as the prestress increases. The details of the
prestress here are described in note S3 and fig. S3. Furthermore,
eventually, the optical outputs tend to zero when the prestress is
more than 160 kPa, and the electrical outputs tend to zero when the
Fig. 2. The triboelectric-optical model. (A) Schematic diagram of the physical model of the triboelectric-optical effect in contact-separation mode. (B) Light intensity
and output voltage of the SUE-skin under different pressures. (C) Light intensity and output voltage of the SUE-skin under different prestress. (D) The spectrogram of tri-
boluminescence (TL) of the SUE-skin. (E) The spectrogram of electroluminescence (EL) of the synthesized ZnS: Cu, Al powder. (F) The spectrogram of room temperature
photoluminescence (PL) of the synthesized ZnS: Cu, Al powder.

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prestress is more than 240 kPa. The reason for this phenomenon is
that the contact is not tight when the prestress is small, and tribo
electricity is generated because the contact becomes tighter in the
subsequent pressure increase. When the prestress is large, then the
adding stress will not produce triboelectricity, and thus, there will
be no electrical and optical output. From another point of view,
although the sphalerite-ZnS having piezoelectricity is used here
(fig. S1D), the outputs of the SUE-skin under touch stimuli are
not caused by the piezoelectric effect. It also proves that the optical
signal output generated by the SUE-skin here is not from the
mechanoluminescence caused by lattice distortion or material cracking.
The comparisons of Fig. 2 (D to F) reveal that the triboluminescence
(TL) of the SUE-skin under touch stimuli is from electroluminescence
(EL) rather than room temperature photoluminescence (PL). A
detailed explanation is given in note S4 and fig. S4.
Besides, we have found that when the liquid flows through
the surface of the SUE-skin, the output optical signals can also be
generated (note S5, fig. S5, and movie S4). This previously unknown
phenomenon can further prove the above working principle of the
SUE-skin. In summary, the total intensity of the electrical output and
light output of the SUE-skin depends on the strength of the tribo
electrification, and the intensity of the two outputs is mutually con-
strained when the strength of the triboelectrification is constant.
Performance optimization of the SUE-skin
In the process of touching, the contact area and pressure of the
human skin and the SUE-skin are difficult to precisely control. So,
in all quantitative tests on the outputs of SUE-skin (fig. S6 for the
schematic of the testing equipment), glass was used instead of human
skin, which is close to the human skin in the triboelectric series
(Fig. 3A). As mentioned above, the outputs of the SUE-skin, whether
electrical or optical, are induced by the triboelectrification. Therefore,
enhancing the strength of frictional electrification is the fundamental
method to optimize the performance of the SUE-skin. Two of the
most recognized methods for improving triboelectrification are the
selection of suitable friction materials and surface treatment, such
as the fabrication of microstructures to increase the surface area and
change the excited state concentration of the surface (38, 39). As
shown in Fig. 3B, the effect of various binders [ethyl cellulose (EC),
methylcellulose (MC), polyvinyl alcohol (PVA), PDMS, and Ecoflex
00-20 (Ecoflex)] on device output was compared. The results are
consistent with the triboelectric series, and the output performances
are best when Ecoflex is used as the binder. As shown in Fig. 3C,
after the surface treatment of Ecoflex by reactive ion etching (RIE),
the output performance of the device is significantly improved.
Characterization of Ecoflex surface morphology before and after
RIE treatment is shown in fig. S7 (A to D). In the above comparison,
the mass ratio of ZnS to Ecoflex is 1:1, and the thickness of the ZnS
and Ecoflex composite is 500 m. For practical interactive applications,
the higher the intensity of the output optical signal, the easier it will
be recognized by the human eye. Therefore, on the premise that the
output voltage can be directly identified by the microcontroller
(without filtering and amplification), we want the intensity of the
output optical signal to be as high as possible. In other words, after
increasing the total output of the SUE-skin by material selection
and surface treatment, the strength of the electrical output and the
light output has to be coordinated.
The main factors affecting the relative strength of the two outputs
are the mass ratio of ZnS to Ecoflex and the thickness of the com-
posite, as shown in Fig. 3 (D and E). When the mass ratio of ZnS to
Ecoflex is increased (as the thickness of the composite is 500 m),
the density of the luminescent center in the same rubbing region is
Fig. 3. Performance optimization of the SUE-skin. (A) The position of different materials in the triboelectric series. (B) The output electrical and optical signals of the
SUE-skin when different materials are used as binders. (C) The output electrical and optical signals of the SUE-skin before and after the reactive ion etching (RIE) process.
(D) The output electrical and optical signals of the SUE-skin when the mixing ratio of ZnS and Ecoflex is different. (E) The output electrical and optical signals of the SUE-
skin when the thickness of the composite is different.

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increased, so the intensity of the output optical signal of the device
is increased. At the same time, since ZnS is a semiconductor, it will
have a shielding effect on the electrostatic induction process of the
SUE-skin. Therefore, as the ratio of ZnS to Ecoflex increases, the
output electrical signal strength of the device will decrease. When
the thickness of the composite is increased (as the mass ratio of ZnS
to Ecoflex is 1:1), the density of the luminescent center in the same
friction region is also increased, so the intensity of the output optical
signal of the device is also increased. Besides, when the mass ratio of
ZnS to Ecoflex is more than 1:1, the composite film is easily cracked
and has reduced elasticity (fig. S7, E to H). However, the higher the
thickness, the longer the electrostatic induction distance for the
SUE-skin, so the output electrical signal is smaller.
To realize that the electrical signal can be accurately recognized by
the microcontroller, the electrical signal must be larger than a certain
thresholdtoensuresufficientanti-interferenceperformanceandsmaller
than the reference voltage inside the microcontroller to avoid break-
down.Forourintegratedcontrolplatform,whentheanaloginputsignal
of the analog-to-digital conversion (ADC) is higher than 0.5 V, it can
achieveverygoodinterferenceimmunity.Also,theanalogvoltageinput
range of the microcontroller is 0 to 3.3 V. In actual tests, when the out-
put voltage of the SUE-skin is about 40 V, the corresponding divided
voltage of the ADC module is about 2.7 V, which just meets the above
requirements. So, the relevant parameters of the SUE-skin are deter-
mined as, friction material (binder), Ecoflex; surface treatment, RIE;
the mass ratio of ZnS and Ecoflex, 1:1; and the thickness of the ZnS
Fig. 4. Demonstration of the programmable touch operation platform by tracks recognition. (A) Schematic diagram of the four-electrode SUE-skin. (B) Optical
photograph and electrodes schematic of the SUE-skin. (C) Schematic diagram of the programmable control module. (D) Touch operation demonstration for audio play-
back. (E) Touch operation demonstration for the characters displaying. Photo credit for (B), (D), and (E): Xuan Zhao, University of Science and Technology Beijing.

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and Ecoflex composite, 500 m. Movie S5 demonstrates the lumines-
cence of the ZnS-Ecoflex composite film rubbed by hand.
Demonstration of the programmable touch
operation platform
Because of its good intuitiveness, the interactive operation has
essential application value in the fields of wearable electronic devices,
industrial Internet, and smart home. We combined the SUE-skin
with a microcontroller to build a programmable touch operation
platform, which can recognize different touch tracks for easy control
of consumer electronics. As shown in Fig. 4 (A to C), each channel
from the SUE-skin is connected to the low-pass resistor-capacitance
filter to decrease electrical noise. Using 10-megohm resistor and
1-nF capacitor, the corresponding cutoff frequency is 15.9 Hz.
The electrical signals generated by the four-electrode SUE-skin
are input to the MCU (STM32F407) and converted into digital
signals by the built-in ADC of the MCU. The MCU is programmed
in LabVIEW embedded by advanced reduced instruction set com-
puting machine to recognize electrical signals of the SUE-skin and
control external devices through drive circuits. The signal process-
ing details and flowcharts are shown in fig. S8. First, the MCU
collects input voltage signals of the SUE-skin by ADC from four pins
(PA0, PA1, PA2, and PA3) and then checks if signals are above the
threshold value. Once signals that exceed the threshold are acquired,
the MCU records the pins that were triggered during a time period
and converts them into a one-dimensional array and then checks if
the array is a preset instruction. If yes, then it converts the resulting
one-dimensional array to a control variable. Different control vari-
ables correspond to different output instructions to control the pe-
ripheral equipment. Because of the intuitive touch lighting and signal
processing technology, this interactive programmable touch operation
platformcansupportmorethan156touchinteractionlogics(seefig.S9).
Figure 4 (D and E) is interactive operation demonstrations of the
control of the external audio module and display module (movies
S6 to S8). As shown in Fig. 4D, when the finger is swiped from the
region 1 to 2, the audio is turned on for music (Hotel California)
playback; when the finger is swiped from the region 1 to 3, the music
is played at 2× speed; and when the finger is swiped from the region 3
to 1, the standard rate is resumed. When the finger is swiped from
the region 2 to 4, the music is played at 0.5× speed; when the finger
is swiped from the region 4 to 2, the standard rate is resumed; and
when the finger is swiped from the region 2 to 1, the music is paused.
The inset map in the lower-left corner of each process shows the
illuminating tracks during the operation. Figure 4E is the photographs
of the luminescence at different touches, the characters displayed
on the external LCD screen, and the real-time electrical signals were
acquired in the four channels. In addition, finger sliding velocity
sensing may be useful for the application of HMI. Here, from the
distance between the center points of different electrodes and the
time difference between the electrical signals generated by different
channels, the sliding speed of the fingertips can be calculated easily.
Moreover, we explored the possibility of high-robust touch track
monitoring with the superposition of electrical and optical signals,
as shown in note S6 and fig. S10.
DISCUSSION
In this work, we demonstrated the concept of SUE-skin, which is
capable of interactive luminescence and tactile-sensing properties
without external power supply. The theoretical basis for realizing
this concept is the triboelectric-optical model, which is effective in
illustrating the mechanism of touch light emission at low trigger
pressure threshold (20 kPa, only 1% compared to the traditional
mechanoluminescence). On the basis of the triboelectric-optical
model, a seamless integration of visual and electrical mapping of
touch stimuli is achieved. The perception of touch stimuli can be
achieved through the observation of human eyes, and the touch
stimuli can be monitored through electrical readout. This work
feature is not only the core of user-interactive e-skin but also a good
solution to poor practicality caused by only optical signal output in
the previous strain visualization. Moreover, by integrating with a
MCU, the SUE-skin can also be used as a programmable touch
operation platform that supports more than 156 interactive logics.
Last, we explored the possibility of high-robust touch track monitor-
ing with the superposition of electrical-optical dual signals. Future
work will involve introducing other electroluminescent materials in
a variety of colors and array designs to achieve higher luminous
intensity, contrast, and resolution. This SUE-skin is suitable for
applications in interactive wearable devices, military applications,
artificial prosthetics, and intelligent robots.
MATERIALS AND METHODS
Preparation of composite film
The synthesized ZnS particles are mixed with the binder in proportion
and stirred well. The mixture was then poured into a homemade
mold. After the adhesive is cured in a vacuum environment, the
composite film is obtained by demolding. The PDMS elastomer
base (Sylgard 184, Dow Corning) was mixed with a 10:1 mixture of
curing agents, and ZnS particles were added and stirred well. The
mixture was then heated at 50°C for 12 hours to cure the PDMS. The
components A and B of Ecoflex (00-20, Smooth-on) were mixed 1:1,
and ZnS particles were added and stirred uniformly. The mixture of
Ecoflex, EC, MC, PVA, and ZnS particles was allowed to stand at
room temperature for 18 hours for curing. The top surface of the
ZnS-Ecoflexcompositefilmwasetched(O2 plasma,100mTorr,100W)
using a reactive ion etcher (Ke Mao, RIE-100).
Fabrication of the SUE-skin
First, an Al electrode (thickness, 300 nm) was evaporated at the bottom
of the composite film, and the wires were taken out. Then, a Kapton
film (thickness, 50 m; DuPont) was pasted as an insulating layer.
A layer of Al (thickness, 150 nm) is further evaporated as a shielding
layer (the shielding layer is always grounded during the use of
the SUE-skin). Last, a layer of PDMS having a thickness of about
0.5 mm was pasted as a substrate.
Device characterization
SEM images were characterized using a JEOL JSM-7001F FEG SEM
operated at 10-kV beam voltage. The contact pressure was measured
by a pressure sensor (SBT671), which is tied to the stepping motor.
Spectrometers (NanoLOG-TCSPC, QE65pro Ocean Optics) in the
range of 300 to 800 nm were carried out to analyze the spectral curve
of the emission light in the touching process, and a multichannel
measurement system (PXIe-4300, National Instruments Corporation)
was used to collect the electric signal. Time-lapse optical photo-
graphs and videos of optical output under sliding touch were
collected by Nikon 7000D (18 to 140 mm). The brightness of

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luminescence under touch stimuli was recorded using a spectro
radiometer (PR-655).
SUPPLEMENTARY MATERIALS
Supplementary material for this article is available at http://advances.sciencemag.org/cgi/
content/full/6/28/eaba4294/DC1
REFERENCES AND NOTES
1. A. Chortos, J. Liu, Z. Bao, Pursuing prosthetic electronic skin. Nat. Mater. 15, 937–950 (2016).
2. J. Wang, M.-F. Lin, S. Park, P. Lee, Deformable conductors for human machine interface.
Mater. Today 21, 508–526 (2018).
3. G.-Z. Yang, J. Bellingham, P. E. Dupont, P. Fischer, L. Floridi, R. Full, N. Jacobstein,
V. Kumar, M. McNutt, R. Merrifield, B. J. Nelson, B. Scassellati, M. Taddeo, R. Taylor,
M. Veloso, Z. Wang, R. Wood, The grand challenges of Science Robotics. Sci. Robot. 3,
eaar7650 (2018).
4. T. Someya, Z. Bao, G. G. Malliaras, The rise of plastic bioelectronics. Nature 540, 379–385 (2016).
5. C.-C. Kim, H.-H. Lee, K. Oh, J.-Y. Sun, Highly stretchable, transparent ionic touch panel.
Science 353, 682–687 (2016).
6. M. Sarwar, Y. Dobashi, C. Preston, J. Wyss, S. Mirabbasi, J. D. W. Madden, Bend, stretch,
and touch: Locating a finger on an actively deformed transparent sensor array. Sci. Adv. 3,
e1602200 (2017).
7. V. Blums, M. Piotrowski, M. I. Hussain, B. G. Norton, S. C. Connell, S. Gensemer, M. Lobino,
E. W. Streed, A single-atom 3D sub-attonewton force sensor. Sci. Adv. 4, eaao4453 (2018).
8. W. Gao, H. Ota, D. Kiriya, K. Takei, A. Javey, Flexible electronics toward wearable sensing.
Acc. Chem. Res. 52, 523–533 (2019).
9. K. Takei, W. Gao, C. Wang, A. Javey, Physical and chemical sensing with electronic skin.
Proc. IEEE 107, 2155–2167 (2019).
10. W. Ding, C. Wu, Y. Zi, H. Zou, J. Wang, J. Cheng, A. C. Wang, Z. Wang, Self-powered wireless
optical transmission of mechanical agitation signals. Nano Energy 47, 566–572 (2018).
11. X. Pu, H. Guo, J. Chen, X. Wang, Y. Xi, C. Hu, Z. Wang, Eye motion-triggered self-powered
mechnosensational communication system using triboelectric nanogenerator. Sci. Adv.
3, e1700694 (2017).
12. S. Lim, D. Son, J. Kim, Y. Lee, J.-K. Song, S. Choi, D. Lee, J. Kim, M. Lee, T. Hyeon, D.-H. Kim,
Transparent and stretchable interactive human machine interface based on patterned
graphene heterostructures. Adv. Funct. Mater. 25, 375–383 (2015).
13. S. Hong, S. Lee, D.-H. Kim, Materials and design strategies of stretchable electrodes
for electronic skin and its applications. Proc. IEEE 107, 2185–2197 (2019).
14. B.-K. Tee, A. Chortos, A. Berndt, A. Nguyen, A. Tom, A. McGuire, Z. Lin, K. Tien, W.-G. Bae,
H. Wang, P. Mei, H.-H. Chou, B. Cui, K. Deisseroth, T. Ng, Z. Bao, A skin-inspired organic
digital mechanoreceptor. Science 350, 313–316 (2015).
15. C. Zhang, H. Wang, S. Guan, Z. Guo, X. Zheng, Y. Fan, Y. Wang, T. Qu, Y. Zhao, A. Chen,
G. Zhu, Z. Wang, Self-powered optical switch based on triboelectrification-triggered
liquid crystal alignment for wireless sensing. Adv. Funct. Mater. 29, 1808633 (2019).
16. J. Kang, B.-H. Jeffrey, Z. Bao, Self-healing soft electronics. Nat. Electronics 2, 144–150 (2019).
17. X. Zhao, Z. Kang, Q. Liao, Z. Zhang, M. Ma, Q. Zhang, Y. Zhang, Ultralight, self-powered
and self-adaptive motion sensor based on triboelectric nanogenerator for perceptual
layer application in Internet of things. Nano Energy 48, 312–319 (2018).
18. J. Kim, G. A. Salvatore, H. Araki, A. M. Chiarelli, Z. Xie, A. Banks, X. Sheng, Y. Liu, J. Lee,
K.-I. Jang, S. Heo, K. Cho, H. Luo, B. Zimmerman, J. Kim, L. Yan, X. Feng, S. Xu, M. Fabiani,
G. Gratton, Y. Huang, U. Paik, J. A. Rogers, Battery-free, stretchable optoelectronic
systems for wireless optical characterization of the skin. Sci. Adv. 2, e1600418 (2016).
19. J. Lee, R. Xu, S. Lee, K.-I. Jang, Y. Yang, A. Banks, K. Yu, J. Kim, S. Xu, S. Ma, S. Jang, P. Won,
Y. Li, B. Kim, J. Choe, S. Huh, Y.-H. Kwon, Y. Huang, U. Paik, J. A. Rogers, Soft, thin
skin-mounted power management systems and their use in wireless thermography.
Proc. Natl. Acad. Sci. U.S.A. 113, 6131–6136 (2016).
20. M. Han, H. Wang, Y. Yang, C. Liang, W. Bai, Z. Yan, H. Li, Y. Xue, X. Wang, B. Akar, H. Zhao,
H. Luan, J. Lim, I. Kandela, G. A. Ameer, Y. Zhang, Y. Huang, J. A. Rogers, Three-
dimensional piezoelectric polymer microsystems for vibrational energy harvesting,
robotic interfaces and biomedical implants. Nat. Electronics 2, 26–35 (2019).
21. K. Takei, T. Toshitake, H. C. Johnny, G. G. Andrew, L. W. Paul, F. S. Ronald, A. Javey,
Nanowire active-matrix circuitry for low-voltage macroscale artificial skin. Nat. Mater. 9,
821–826 (2010).
22. S. Mannsfeld, B. C.-K. Tee, R. M. Stoltenberg, C. V. H.-H. Chen, S. Barman, B. V. O. Muir,
A. N. Sokolov, C. Reese, Z. Bao, Highly sensitive flexible pressure sensors
with microstructured rubber dielectric layers. Nat. Mater. 9, 859–864 (2010).
23. D. J. Lipomi, M. Vosgueritchian, B. C.-K. Tee, S. L. Hellstrom, J. A. Lee, C. H. Fox, Z. Bao,
Skin-like pressure and strain sensors based on transparent elastic films of carbon
nanotubes. Nat. Nanotechnol. 6, 788–792 (2011).
24. M. Ma, Z. Kang, Q. Liao, Q. Zhang, F. Gao, X. Zhao, Z. Zhang, Y. Zhang, Development,
applications, and future directions of triboelectric nanogenerators. Nano Res. 11,
2951–2969 (2018).
25. B. C.-K. Tee, C. Wang, R. Allen, Z. Bao, An electrically and mechanically self-healing
composite with pressure- and flexion-sensitive properties for electronic skin applications.
Nat. Nanotechnol. 7, 825–832 (2012).
26. W. Wu, X. Wen, Z. Wang, Taxel-addressable matrix of vertical-nanowire piezotronic
transistors for active and adaptive tactile imaging. Science 340, 952–957 (2013).
27. J. Kim, M. Lee, H. Shim, R. Ghaffari, H. Cho, D. Son, Y. Jung, M. Soh, C. Choi, S. Jung, K. Chu,
D. Jeon, S.-T. Lee, J. Kim, S. Choi, T. Hyeon, D.-H. Kim, Stretchable silicon nanoribbon
electronics for skin prosthesis. Nat. Commun. 5, 5747 (2014).
28. C. Wang, D. H, Z. Yu, K. Takei, J. Park, T. Chen, B. Ma, A. Javey, User-interactive electronic
skin for instantaneous pressure visualization. Nat. Mater. 12, 899–904 (2013).
29. H. Chou, A. Nguyen, A. Chortos, J. W. F. To, C. Lu, J. Mei, J. G. T. Kurosawa, W.-G. Bae,
J. B.-H. Tok, Z. Bao, A chameleon-inspired stretchable electronic skin with interactive
colour changing controlled by tactile sensing. Nat. Commun. 6, 8011 (2015).
30. C. Larson, B. Peele, S. Li, S. Robinson, M. Totaro, L. Beccai, B. Mazzolai, R. Shepherd, Highly
stretchable electroluminescent skin for optical signaling and tactile sensing. Science 351,
1071–1074 (2016).
31. X. Wang, M. Que, M. Chen, X. Han, X. Li, C. Pan, Z. Wang, Full dynamic-range pressure
sensor matrix based on optical and electrical dual-mode sensing. Adv. Mater. 29, 1605817
(2017).
32. X. Wei, X. Wang, S. Kuang, L. Su, H. Li, Y. Wang, C. Pan, Z. Wang, G. Zhu, Dynamic
triboelectrification-induced electroluminescence and its use in visualized sensing.
Adv. Mater. 28, 6656–6664 (2016).
33. X. Wei, L. Liu, H. Wang, S. Kuang, X. Zhu, Z. Wang, Y. Zhang, G. Zhu, High-intensity
triboelectrification-induced electroluminescence by microsized contacts for self-
powered display and illumination. Adv. Mater. Interfaces 5, 1701063 (2018).
34. Y. Wang, H. Wang, H. Li, X. Wei, Z. Wang, G. Zhu, Enhanced high-resolution
triboelectrification-induced electroluminescence for self-powered visualized interactive
sensing. ACS Appl. Mater. Interfaces 11, 13796–13802 (2019).
35. H. Park, S. Kim, J. Lee, H. Kim, W. Seung, Y. Son, T. Kim, U. Khan, N. Park, S. Kim,
Self-powered motion-driven triboelectric electroluminescence textile system.
ACS Appl. Mater. Interfaces 11, 5200–5207 (2019).
36. Y. Park, Topics in Applied Physics, Electroluminescence, Recent advances in injection
luminescence in II–VI compounds (Springer, 1977), vol. 17.
37. H. Henisch, International Series of Monographs on Semiconductors, Electroluminescence
(Pergamon, 1962), vol. 5, chap. 2.
38. G. Zhu, C. Pan, W. Guo, C. Chen, Y. Zhou, R. Yu, Z. Wang, Triboelectric-generator-driven
pulse electrodeposition for micropatterning. Nano Lett. 12, 4960–4965 (2012).
39. A. Wang, I. Greber, J. Angus, Contact charge transfer between inorganic dielectric solids
of different surface roughness. J. Electrost. 101, 103359 (2019).
40. L. Qi, B. Lee, X. Gu, M. Grujicic, W. Samuels, G. Exarhos, Concentration efficiency of doping
in phosphors: Investigation of the copper- and aluminum-doped zinc sulfide.
Appl. Phys. Lett. 83, 4945–4947 (2003).
Acknowledgments
Funding: This work was supported by the National Key Research and Development Program of
China (nos. 2018YFA0703500 and 2016YFA0202701), National Natural Science Foundation of
China (nos. 51991340, 51722203, 51672026, and 51527802), the Overseas Expertise Introduction
Projects for Discipline Innovation (B14003), and the Fundamental Research Funds for Central
Universities (FRF-TP-18-001C1). Author contributions: X.Z., Z.Z., Q.L., and Y.Z. conceived the
concept, processing, and structure details. X.Z., Z.Z., and Q.L. prepared and purified the
materials. X.X. and Z.K. assisted in carrying out the SUE-skin fabrication. X.X., F.G., and X.X.
assisted in the SUE-skin performance measurements. X.Z. built the programmable touch
operation platform. X.Z., Q.L., and Y.Z. co-wrote the paper. All authors discussed the results
and commented on the manuscript. Competing interests: The authors declare that they have
no competing interests. Data and materials availability: All data needed to evaluate the
conclusions in the paper are present in the paper and/or the Supplementary Materials.
Additional data related to this paper may be requested from the authors.
Submitted 3 December 2019
Accepted 22 May 2020
Published 8 July 2020
10.1126/sciadv.aba4294
Citation: X. Zhao, Z. Zhang, Q. Liao, X. Xun, F. Gao, L. Xu, Z. Kang, Y. Zhang, Self-powered user-
interactive electronic skin for programmable touch operation platform. Sci. Adv. 6, eaba4294
(2020).

Self-powered user-interactive electronic skin for programmable touch operation platform
Xuan Zhao, Zheng Zhang, Qingliang Liao, Xiaochen Xun, Fangfang Gao, Liangxu Xu, Zhuo Kang and Yue Zhang
DOI: 10.1126/sciadv.aba4294
(28), eaba4294.6Sci Adv
ARTICLE TOOLS http://advances.sciencemag.org/content/6/28/eaba4294
MATERIALS
SUPPLEMENTARY http://advances.sciencemag.org/content/suppl/2020/07/06/6.28.eaba4294.DC1
REFERENCES
http://advances.sciencemag.org/content/6/28/eaba4294#BIBL
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