Search

There is a growing need for research on self‐healing materials capable of spontaneously repairing physical damage, allowing the fabrication of highly durable wearable devices featuring flexibility and stretchability. Herein, the study reports on the fabrication of a novel, magnetically aligning, fully and rapidly self‐healing skin‐attachable biosensor based on newly synthesized photothermally self‐healing polyurethane. By introducing photothermal amine‐capped aniline trimers to selectively self‐healable polyurethane, the synthesized self‐healing polymer achieves a fast and high recovery rate of 81.1% from complete bisection upon laser irradiation for just 3 min. Additionally, a thin‐film type strain sensor fabricated via the spray patterning of liquid metal EGaIn as an electrode onto the surface of the self‐healing polymer exhibits a high sensitivity to strain from deformation, enabling the real‐time monitoring of bio‐signals. Furthermore, the integration of a magnetic aligning layer directly patterned and embedded onto the self‐healing polymer enhances the self‐healing performance of the sensor after damage by 4.3 times on average, compared to when using manual alignment. In short, this work demonstrates a high‐performance fully self‐healing electronic device via the synthesis of novel fast self‐healing photothermal polymers and the introduction of patterned liquid metal electrodes and magnetic alignment layers. [ABSTRACT FROM AUTHOR]

A fully self‐healing sensor patch consisting of an in‐plane integrated dual‐mode sensor and a pressure sensor with a vertically integrated electrocardiogram (ECG) electrode is reported. For a full‐device self‐healing, interlayer self‐bonding by using self‐healing oxime‐carbamate bond‐based polyurethane and room temperature self‐healing TUEG3 capped Au nanosheet (T‐Au NS) electrodes are devised. Via the use of a self‐healing sensor foam prepared by a coating of a self‐healing composite of polyurethane and polyaniline onto a microporous graphene foam, a self‐healing dual‐mode sensor is fabricated to detect the pressure and temperature simultaneously without interference. Furthermore, the interdigitated self‐healing electrode of T‐Au NS is applied to the pressure sensor to enhance the sensitivity up to 208.62 kPa−1 (<1 kPa), enabling the detection of small pulse signals even after multiple self‐healing events. By using the common self‐healing T‐Au NS electrode vertically integrated onto the sensor patch, ECG signals are also detected. With this sensor patch, skin temperature, wrist pulse, and ECG signals are successfully detected after a simultaneous full‐device self‐healing from complete bisection. This study demonstrates the facile fabrication of a high‐performance, fully self‐healing patch of multi‐sensors via the deliberate selection of sensor design and the associated functional materials, confirming its high potential applicability to highly durable health monitoring systems. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) and graphene have commonly been applied as the sensitive layer of strain sensors. However, the buckling deformation of CNTs and the crack generation of graphene usually leads to an unsatisfactory strain sensing performance. In this work, we developed a universal strategy to prepare welded CNT–graphene hybrids with tunable compositions and a tunable bonding strength between components by the in situ reduction of CNT–graphene oxide (GO) hybrid by thermal annealing. The stiffness of the hybrid film could be tailored by both initial CNT/GO dosage and annealing temperature, through which its electromechanical behaviors could also be defined. The strain sensor based on the CNT–graphene hybrid could be applied to collect epidermal bio-signals by both capturing the faint skin deformation from wrist pulse and recording the large deformations from joint bending, which has great potential in health monitoring, motion sensing and human–machine interfacing. [ABSTRACT FROM AUTHOR]

[Display omitted] • A fully self-healing supercapacitor is demonstrated for wearable electronics. • The supercapacitor is stable over 40% stretching even after repetitive self-healing. • The supercapacitor is stable over repeated temperature changes from −20 to 60 ℃. • With integrated patch of supercapacitor and strain sensor, bio-signals are detected. • The patch device works successfully even after self-healing over −20 and 60 ℃. In this study, we demonstrate a stretchable, fully self-healable, temperature-tolerant, and water-proof supercapacitor with high electrochemical performance via a deliberate selection of materials and device architecture. Distinct from previous works, our whole supercapacitor is stretchable and self-healable, owing to the application of specially devised stretchable and self-healing oxime-carbamate based polyurethane (OC-PU) substrate film, self-healing polymer (poly(ether-thioureas) triethylene glycol) capped Au nanosheet current collector (TUEG 3 -Au NS) and newly synthesized organohydrogel electrolyte. The fabricated supercapacitor exhibits a high electrochemical performances (specific capacitance of 165.5F g−1, energy density of 14.58 Wh kg−1, power density of 2181.75 W kg−1, and capacitance retention of 89 % after 10,000 cycles) with a capacitance retention of 81 % over stretching by 40 % even after repetitive healing from damages, the self-healing of all components (full self-healing) over repetitive damages with a capacitance recovery by over 83 %, a wide operational temperature range from −20 to 60 °C with retaining over 91 % of capacitance at RT. Furthermore, a μ-LED is stably operated with the supercapacitor immersed in water regardless of the mechanical deformation and self-healing from damage due to self-bonded encapsulation layer of hydrophobic OC-PU film. With a vertically integrated patch device consisting of the fabricated supercapacitor and a strain sensor, bio-signals are detected using the stored energy of the supercapacitor even after self-healing from damages over the temperature range from −20 to 60 °C. This work suggests the high application potential of our high performance multi-functional supercapacitor as an integrated energy storage device for wearable electronics featuring longevity and stability under harsh environments. [ABSTRACT FROM AUTHOR]

‘Many worlds’ is a short narrative live-action film written and directed so as to provide multiple linear routes through the plot to one of four endings, and designed for showing in a cinema environment. At two points during the film, decisions are made based on audience bio-signals as to which plot route to take. The use of bio-signals is to allow the audience to remain immersed in the film, rather than explicitly selecting plot direction. Four audience members have a bio-signal measured sensor for each person: ECG (heart rate), EMG (muscle tension), EEG (‘brain waves’) and Galvanic Skin Response (perspiration). The four are interpreted as a single average of emotional arousal. ‘Many worlds’ was the first live-action linear plotted film to be screened in a cinema to the general public utilizing multiple biosensor types. The film has been shown publically a number of times, and lessons learned from the technical and cinematic production are detailed in this paper. [ABSTRACT FROM AUTHOR]

In the past few years, a significant amount of breakthroughs in the research field of nanosheets have made them possible for broad applications of wearable sensors. Compared with nanoparticles (NPs) and one-dimensional nanofibers or nanotubes, however, nanosheets (as two-dimensional materials) manifest superior physical and electrochemical properties and the potential of constructing wearable electronic composites. The high surface-to-volume ratio and high flexibility of the nanosheets endow the sensors with small size and high stability under deformation, making sensors portable and wearable. In this review, the state-of-the-art advances of wearable sensors based on nanosheets are discussed systematically in three categories, e.g., motion detection, bio-signal monitoring, and environmental applications. Finally, the future perspectives and outlooks towards the development of wearable sensors are prospected. • Nanosheets possess high surface-to-volume ratio which is suitable substrate for wearable sensors. • Body motion can be monitored by nanosheets-based wearable sensors with high flexibility. • Wearable sensors based on nanosheets can monitor bio-signals in real-time. • Nanosheets-based wearable sensors can interact with the ambient environment for harmful gas detection. [ABSTRACT FROM AUTHOR]

With the development of mobile and wearable devices with biosensors, various healthcare services in our life have been recently introduced. A significant issue that arises supports the smart interface among bio-signals developed by different vendors and different languages. Despite its importance for convenient and effective development, however, it has been nearly unexplored. This paper focuses on the smart interface format among bio-signal data processing and mining algorithms implemented by different languages. We designed and implemented an advanced software structure where analysis algorithms implemented by different languages and tools would seem to work in one common environment, overcoming different developing language barriers. By presenting our design in this paper, we hope there will be much more chances for higher service-oriented developments utilizing bio-signals in the future. [ABSTRACT FROM AUTHOR]

We report on the fabrication of a high performance flexible micro-supercapacitor (MSC) for powering a vertically integrated skin-attachable strain sensor on a gecko-inspired micro-structured adhesive. Combined utilization of the mixed manganese/vanadium (Mn/V) oxide grown on MWCNT electrode and the sulfone-based electrolyte, PC/SL/LiClO 4 /PMMA, enhances both the capacitance and operation voltage up to 2 V of MSC. Thus, the fabricated MSC exhibits excellent electrochemical performance with an areal capacitance of 11.8 mF cm − 2 and an areal energy density of 6.58 µWh cm − 2 at an areal power density of 200 µW cm − 2. The MSC shows mechanical stability over 1000 repetitive bends at a bending radius of 3.7 mm. The strain sensor made of fragmentized graphene foam embedded in PDMS film provides a high gauge factor of 12.6 up to 50% strain to detect strains due to various bio-signals. Our gecko-inspired adhesive made of PDMS micropillars inked with a mixture of PDMS and Silbione to have spatula tips exhibits not only high adhesion property but also high durability over repeated cycles of attachment-detachment and negligible skin irritation. After vertical integration of the MSC, strain sensor, and the adhesive film, bio-signals such as an arterial pulse, swallowing, and frowning of the brow are successfully detected using energy stored in the MSC. [Display omitted] • High-performance micro-supercapacitor (MSC) was fabricated with mixed metal oxide electrode and sulfone-based electrolyte. • Mixed oxide electrode enhanced the capacitance and sulfone-based electrolyte widened operation voltage window of MSC. • Skin-attached fragmentized graphene foam strain sensor with a micro-structured adhesive detected bio-signals. • The strain sensor was operated using the stored energy of the vertically integrated MSC. • MSC was demonstrated as an integrated energy storage device for bio-signal monitoring. [ABSTRACT FROM AUTHOR]