A high-performance, biocompatible, and degradable piezoresistive-triboelectric hybrid device for cross-scale human activities monitoring and self-powered smart home system
Graphical Abstract
Introduction
With the increasing demand for health and life quality of humans, wearable electronic devices have been widely applied in health monitoring [1], [2], [3] and smart home frameworks in Internet of Things (IoT) [4], [5], [6]. Due to the conspicuous merits of simple structure and high sensitivity [7], [8], [9], a flexible piezoresistive sensor that relies on the resistance changing to respond to external pressure serves as one of the most important components in wearable electronic devices and becomes the emphasis of extensive attention and research [10], [11], [12], [13]. To date, much effort has been dedicated to improving the performance of such a piezoresistive sensor including high sensitivity and broad response range, which enables the piezoresistive sensor to achieve cross-scale monitoring from weak physiological signals to high-intensity motion signals and thus better meet the need of health monitoring [14], [15], [16], [17], [18]. For example, Cheng et al. proposed an active layer with a bioinspired micro-spinous structure and effectively improved the sensitivity of the flexible piezoresistive sensor, offering an opportunity to accurately monitor weak signals like pulse [19]. And recently, a broad response range of 0–218 kPa was realized by Zhao and coworkers, which endowed the flexible piezoresistive sensor with a capability of identifying strong signals like finger joint movement [20]. However, most of the reported studies mainly focused on the promotion of either sensitivity or the response range merely [19], [20], [21], [22], and the combination of high sensitivity and broad response range in a flexible piezoresistive sensor is still a great challenge. In addition, considering the huge total power consumption of the wearable electronic products in IoT, triboelectric nanogenerator (TENG), a self-powered electronic device relying on the coupling effect of contact electrification and electrostatic induction [23], [24], has become one of the current research hotspots [25], [26], [27], [28], [29]. By introducing a series of nano-micro scale functional layers, such as nanofibers (NFs) [30], nanowires [31], and fish-scale-like arrays [32], researchers developed TENGs with high electrical output performance and successfully applied the TENGs as sustainable power units in the application of power supply system [33], [34]. More importantly, the TENG is capable of operating as a self-powered sensor without an additional power supply, which is potential for the construction of smart home systems [35], [36].
Currently, most of the wearable electronics adopt synthetic polymers as substrates and matrix materials, which may cause skin problems such as redness after long-time wear [37], [38], [39]. Accordingly, there is an urgent need to develop wearable electronic devices equipped with preferable biocompatibility, allowing the devices to be more suitable for long-term adhesion to the human skin. Beyond that, the non-degradation problem faced by most wearable electronics is easy to trigger the so-called “micro-nano plastic crisis” [40] as well as the accident potential of private information leakage, bringing out a great negative effect on the living environment and information security of humans. Therefore, one shall not limit the research focus on realizing excellent sensing performance, and it is also necessary to design and construct wearable electronic devices with favorably biocompatibility and degradability, which is of great significance to personal health, environmental protection, and information security.
In view of the aforementioned challenges, a flexible piezoresistive-triboelectric hybrid device (PTHD) is proposed, of which the functional layers are prepared based on a facile electrospinning technology followed by selected infiltration treatment (Fig. 1a and b). The PTHD not only enables high-sensitive detection of pressure over a broad range and a remarkable self-powered capability, but also exhibits excellent biocompatibility and degradability. Thereinto, in conjunction with the intentionally introduced bottom stable resistance layer, the piezoresistive layer allows the proposed PTHD to simultaneously achieve the detection of pressure information with high sensitivity and a broad range. Benefiting from that, the proposed PTHD accomplishes the cross-scale monitoring of human signals ranging from tiny deformation of the pulse signal to large-scale movement of the running signal. In addition, several prospective applications of the PTHD in a self-powered smart home system including the real-time aged falls alarm, smart home appliances control and smart entrance guard management are successfully explored (Fig. 1c). Moreover, the success of the cell culture experiment by using the proposed PTHD demonstrates its excellent biocompatibility. Lastly, the proposed PTHD is rapidly dissolved when we soak it in the deionized water and conduct sonication, which shows its superior degradability and potential in the field of transient electronics. Considering the above merits, the proposed PTHD presents a powerful way for constructing wearable electronics that enable both cross-scale pressure detection and self-powered sensing and provides a guiding approach for wearable electronics evolving towards the characteristics that are harmless to physical wellness, conducive to sustainable development, and capable of ensuring information security.
Section snippets
Structure design and fabrication process of the PTHD
Fig. 1a shows the schematic diagram of the proposed PTHD, which integrates a piezoresistive part that enables the highly sensitive detection of the pressure over a broad range and a triboelectric part that endows a remarkable self-powered capability, aiming at realizing the hybrid functions of the PTHD by the two different parts. The piezoresistive part is comprised of polyvinyl alcohol (PVA)/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) NFs film as the bottom stable
Conclusion
In this work, PTHD, a flexible piezoresistive-triboelectric hybrid device is proposed with high sensitivity over a broad pressure range and excellent self-powered capability, incorporated with desirable biocompatibility and degradability. Here, to improve the sensitivity and response range of the PTHD toward the pressure, the PVA/PEDOT:PSS bottom stable resistance layer is ingeniously introduced to work together with the Zein/PVA/CNT piezoresistive layer, both of which are fabricated by the
Fabrication of the PVA/PEDOT:PSS NFs film
To better pursue the biocompatibility and degradability of the PTHD, PVA and PEDOT:PSS are selected to fabricate the PVA/PEDOT:PSS bottom stable resistance layer, which have been widely used as the substrate and conductive filler owing to their superior biocompatibility, environmental friendliness, and easy access [50], [51]. Firstly, 10 wt% PVA solution was prepared by dissolving the PVA (RHAWN, China) in deionized water at 85 ℃ with stirring. The PVA NFs film was prepared by electrospinning
CRediT authorship contribution statement
Huiyun Zhang: Experiment, Writing – original draft, Software. Feifei Yin: Experiment, Writing – original draft, Software. Shuo Shang: Experiment, Validation. Yang Li: Conceptualization, Methodology, Writing – review & editing, Supervision. Zhicheng Qiu: Experiment, Software. Qinghui Lin: Experiment, Software. Xiao Wei: Experiment, Software. Shouliang Li: Experiment, Software. Nam Young Kim: Writing – review & editing. Guozhen Shen: Conceptualization, Methodology, Supervision.
Declaration of Competing Interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Acknowledgement
This work was supported by the National Natural Science Foundation of China under Grant (62174068, 61888102), Rizhao City Key Research and Development Program under Grant (2021ZDYF010102), and Project of Shan dong Province Higher Educational Youth Innovation Science and Technology Program under Grant (2019KJN028).
References (53)
- et al.
A highly stretchable and deformation-insensitive bionic electronic exteroceptive neural sensor for human-machine interfaces
Nano Energy
(2021) - et al.
Technology evolution from self-powered sensors to AIoT enabled smart homes
Nano Energy
(2021) - et al.
A high-accuracy, real-time, intelligent material perception system with a machine-learning-motivated pressure-sensitive electronic skin
Matter
(2022) - et al.
Sensitive piezoresistive sensors using ink-modified plant fiber sponges
Chem. Eng. J.
(2020) - et al.
A skin-like sensor for intelligent braille recognition
Nano Energy
(2020) - et al.
Flexible triboelectric generator
Nano Energy
(2012) - et al.
Improved triboelectrification effect by bendable and slidable fish-scale-like microstructures
Nano Energy
(2017) - et al.
Harsh environment–tolerant and robust triboelectric nanogenerators for mechanical-energy harvesting, sensing, and energy storage in a smart home
Nano Energy
(2021) - et al.
Transparent, stretchable and degradable protein electronic skin for biomechanical energy scavenging and wireless sensing
Biosens. Bioelectron.
(2020) - et al.
Multifunctional and highly sensitive piezoresistive sensing textile based on a hierarchical architecture
Compos Sci. Technol.
(2020)
The arterial pulse in health and disease
Am. Heart J.
Antibacterial bone substitute of hydroxyapatite and magnesium oxide to prevent dental and orthopaedic infections
Mater. Sci. Eng. C
Biomaterials of PVA and PVP in medical and pharmaceutical applications: perspectives and challenges
Biotechnol. Adv.
Bimetallic nanocatalysts immobilized in nanoporous hydrogels for long-term robust continuous glucose monitoring of smart contact lens
Adv. Mater.
Active‐matrix sensing array assisted with machine‐learning approach for lumbar degenerative disease diagnosis and postoperative assessment
Adv. Funct. Mater.
Wearable triboelectric sensors enabled gait analysis and waist motion capture for IoT-based smart healthcare applications
Adv. Sci.
IoT wearable sensor and deep learning: An integrated approach for personalized human activity recognition in a smart home environment
IEEE Internet Things J.
Highly stretchable resistive pressure sensors using a conductive elastomeric composite on a micropyramid array
Adv. Mater.
Ultrahigh-sensitivity piezoresistive pressure sensors for detection of tiny pressure
ACS Appl. Mater. Interfaces
Micro-nano processing of active layers in flexible tactile sensors via template methods: a review
Small
Learning the signatures of the human grasp using a scalable tactile glove
Nature
Flexible piezoresistive sensor patch enabling ultralow power cuffless blood pressure measurement
Adv. Funct. Mater.
Ultrafast-response/recovery flexible piezoresistive sensors with DNA-like double helix yarns for epidermal pulse monitoring
Adv. Mater.
Giant tunneling piezoresistance of composite elastomers with interlocked microdome arrays for ultrasensitive and multimodal electronic skins
ACS Nano
Touchpoint-tailored ultrasensitive piezoresistive pressure sensors with a broad dynamic response range and low detection limit
ACS Appl. Mater. Interfaces
Epidermis-inspired wearable piezoresistive pressure sensors using reduced graphene oxide self-wrapped copper nanowire networks
Small Methods
Cited by (17)
Environmental energy harvesting boosts self-powered sensing
2024, Materials Today EnergyRecent Progress in Application-Oriented Self-Powered Microelectronics
2023, Advanced Energy Materials
- 1
These authors contributed equally: Huiyun Zhang, Feifei Yin, Shuo Shang.