Extensible Integrated System for Real-Time Monitoring of Cardiovascular Physiological Signals and Limb Health.

In recent decades, the rapid growth in flexible materials, new manufacturing technologies, and wearable electronics design techniques has helped establish the foundations for noninvasive photoelectric sensing systems with shape-adaptability and "skin-like" properties. Physiological sensing includes humidity, mechanical, thermal, photoelectric, and other aspects. Photoplethysmography (PPG), an important noninvasive method for measuring pulse rate, blood pressure, and blood oxygen, uses the attenuated signal obtained by the light absorbed and reflected from living tissue to a light source to realize real-time monitoring of human health status. This work illustrates a patch-type optoelectronic system that integrates a flexible perovskite photodetector and all-inorganic light-emitting diodes (LEDs) to realize the real-time monitoring of human PPG signals. The pulse rate of the human body and the swelling degree of finger joints can be extracted and analyzed using photodetectors, thus monitoring human health for the prevention and early diagnosis of certain diseases. Specifically, this work develops a 3D wrinkled-serpentine interconnection wire that increases the shape adaptability of the device in practical applications. The PPG signal sensor reported in this study has considerable potential for future wearable intelligent medical applications.

Reversible self-powered fluorescent electrochromic windows driven by perovskite solar cells.

Self-powered electrofluorochromic devices (EFCDs) have attracted particular attention for smart windows of green buildings. In this work, we report a perovskite solar cell (PSC) driven self-powered EFCD. For the first time, electrochromic material polyoxometalates (POMs) and a fluorescent component are made into wet adhesives. A special design feature is that POMs and magnesium composed a battery powering the EFCD bleaching, and the device can be quickly coloured after connecting with the PSCs by the electrical power generated through solar energy conversion. Therefore, without any additional external bias, the fabricated EFCD undergoes an electrochromic transition from white semitransparent to dark blue-tinted, and under UV it presents reversible fluorescence switching between yellow and dark.

Self-Rechargeable-Battery-Driven Device for Simultaneous Electrochromic Windows, ROS Biosensing, and Energy Storage.

A self-powered electrochromic device (ECD) powered by a self-rechargeable battery is easily fabricated to achieve electrochromic window design, quantitative reactive oxygen species (ROS) sensing, and energy storage. The special design of the battery was composed of Prussian blue (PB) and magnesium metal as the cathode and anode, respectively, which exhibits fast self-charging and high power-density output for continuous and stable energy supply. Benefitting from the fast electrochromic response of PB, it was not only used for structuring self-rechargeable batteries but also used as an electrochromic display for highly sensitive self-powered ROS sensing and visual analysis. We believe that this work provides a solution to self-powered ECDs limited to a single application and could combine the applications in smart windows, ROS sensing, and other fields together, and in the meantime provide a solution for energy supply problems.