RESUMEN
Air, a widely recognized dielectric material, is employed as a dielectric layer in this study. We present a triboelectric sensor with a laser-induced graphene (LIG) electrode and an air-trapped pad using silicone rubber (SR). A very thin device with a thickness of 1 mm and an effective gap for contact-separation between the films of silicone rubber and polyimide (PI) of 0.6 mm makes the device extremely highly sensitive for very low amplitudes of pressure. The fabrication of LIG as an electrode material on the surface of PI is the key reason for the fabrication of the thin sensor. In this study, we showed that the fabricated air-trapped padded sensor (ATPS) has the capability to generate an output voltage of ~32 V, a short-circuit current of 1.2 µA, and attain a maximum power density of 139.8 mW m-2. The performance of the ATPS was compared with a replicated device having a hole on the pad, allowing air to pass through during contact-separation. The observed degradation in the electrical output suggests that the trapped air in the pad plays a crucial role in enhancing the output voltage. Therefore, the ATPS emerges as an ultra-sensitive sensor for healthcare sensing applications.
RESUMEN
The triboelectric nanogenerator (TENG) is a promising research topic for the conversion of mechanical to electrical energy and its application in different fields. Among the various applications, self-powered bio-medical sensing application has become popular. The selection of a wide variety of materials and the simple design of devices has made it attractive for the applications of real-time self-powered healthcare sensing systems. Human activity is the source of mechanical energy which gets converted to electrical energy by TENG fitted to different body parts for the powering up of the biomedical sensing and detection systems. Among the various techniques, wearable sensing systems developed by TENG have shown their merit in the application of healthcare sensing and detection systems. Some key studies on wearable self-powered biomedical sensing systems based on TENG which have been carried out in the last seven years are summarized here. Furthermore, the key features responsible for the highly sensitive output of the self-powered sensors have been briefed. On the other hand, the challenges that need to be addressed for the commercialization of TENG-based biomedical sensors have been raised in order to develop versatile sensitive sensors, user-friendly devices, and to ensure the stability of the device over changing environments.
RESUMEN
Long-range antiferromagnetic coupling impeded electron flow through the hexaradical-containing tetranuclear CoIII4 complex (1), while the nonradical-containing tetranuclear CoIII4 complex (2), with no paramagnetic centres, was a semiconductor and sensed NH3 efficiently at room temperature (25 °C).
RESUMEN
The emergence of organic-inorganic hybrid perovskites (OHPs) has revolutionised the potential performance of optoelectronic devices; most perovskites are opaque and hence incompatible with transparent optoelectronics and sensitive to environmental degradation. Here, we have reported a single-step fabrication of ultra-long MAPbI3 perovskite microwire arrays over a large area using stencil lithography based on sequential vacuum sublimation. The environmental stability of MAPbI3 is empowered with a newly designed and synthesized transparent supramolecular self-assembly based on a mixture of two tripodal l-Phe-C11H23/C7F15 molecules, which showed a contact angle of 105° and served as ultra-hydrophobic passivation layers for more than 45 days in an ambient atmosphere. The MAPbI3 microwire arrays passivated with the supramolecular self-assembly demonstrated for the first time both excellent transparency of â¼89% at 550 nm and a remarkable photoresponse with a photo-switching ratio of â¼104, responsivity of 789 A W-1, detectivity of 1014 Jones, linear dynamic range of â¼122 dB, and rise time of 432 µs. Furthermore, the photodetector fabricated on a flexible PET substrate demonstrated robust mechanical flexibility even beyond 1200 bending cycles. Therefore, the scalable stencil lithography and supramolecular passivation approaches have the potential to deliver next-generation transparent, flexible, and stable optoelectronic devices.
RESUMEN
Triboelectric nanogenerators (TENGs) are smart alternative energy harvesters to convert mechanical energy into electrical energy to power small and portable electronic devices. A key challenge in fabricating an efficient TENG lies in the choice of an active material in addition to the mechanical stability and robust output performance of the device. This report suggests, for the first time, the use of a peritoneum membrane as a triboelectrically positive material for designing TENGs. The peritoneum covers the abdominal wall and diaphragm of mammals except for the kidneys and the adrenal glands and consists of a structure of a well-defined network of elastic fibers. Our peritoneum-based TENG (p-TENG) can generate an open-circuit output voltage of â¼550 V, output current density of â¼100 mA m-2, and instantaneous output power density of 9.4 Wm-2. This work demonstrates the p-TENG as a portable power source, a self-powered pedometer, and a speedometer, which conveys its futuristic applications for health care purposes. Our p-TENG is highly stable, delivering a constant output voltage of â¼550 V over a period of 90 days. The introduction of a biowaste peritoneum membrane as a triboelectrically positive component in the TENG has great potential as a portable alternative energy source owing to its abundance, stability, low cost, and ease of fabrication.