In recent years, vital signals monitoring in sports and health have been considered the research focus in the field of wearable sensing technologies. Typical signals include bioelectrical signals, biophysical signals, and biochemical signals, which have applications in the fields of athletic training, medical diagnosis and prevention, and rehabilitation. In particular, since the COVID-19 pandemic, there has been a dramatic increase in real-time interest in personal health. This has created an urgent need for flexible, wearable, portable, and real-time monitoring sensors to remotely monitor these signals in response to health management. To this end, the paper reviews recent advances in flexible wearable sensors for monitoring vital signals in sports and health. More precisely, emerging wearable devices and systems for health and exercise-related vital signals (e.g., ECG, EEG, EMG, inertia, body movements, heart rate, blood, sweat, and interstitial fluid) are reviewed first. Then, the paper creatively presents multidimensional and multimodal wearable sensors and systems. The paper also summarizes the current challenges and limitations and future directions of wearable sensors for vital typical signal detection. Through the review, the paper finds that these signals can be effectively monitored and used for health management (e.g., disease prediction) thanks to advanced manufacturing, flexible electronics, IoT, and artificial intelligence algorithms; however, wearable sensors and systems with multidimensional and multimodal are more compliant.

Improved efficiency and stability of the organic solar cells (OSCs) are the critical considerations for practical applications. The interface between the interlayer and bulk heterojunction has recently been shown as one of the weak links associated with the degradation in the nonfullerene acceptor (NFA)‐based OSCs. It shows that the removal of the interfacial chemical reactions between the 2‐(3‐oxo‐2,3‐dihydroinden‐1‐ylidene)malononitrile (INCN) moieties in NFA and poly(3,4‐ethylenedioxythiophene)‐polystyrene sulfonate (PEDOT:PSS) hole extraction layer (HEL) is desired for enhancing the device stability. In this work, we show that the use of a bilayer MoO₃/antimonene HEL favors the operational stability in OSCs through maintaining a high built‐in potential and suppression of an undesired interfacial reaction between INCN moieties in NFA and the PEDOT structures in PEDOT:PSS. A power conversion efficiency of 16.68% is also obtained for the OSCs with a bilayer MoO₃/antimonene HEL, prepared using a blend system of PM6:Y6, demonstrating its suitability for high‐performance OSCs. image

Electrospinning is a versatile technique, which can be used to generate nanofibers from a rich variety of materials. We investigate the variation of a zinc oxide (ZnO)-polyvinylpyrrolidone (PVP) composite structure in morphology by electrospinning from a series of mixture solutions of ZnO sol–gel and PVP. Calcination conditions for the crystallization of ZnO nanofibers and removal of the PVP component from the ZnO-PVP composite nanofibers were also studied. The progression of the ZnO-PVP composite structure from grains to nanofibers was observed, and ZnO-PVP nanofibers as thin as 29.9 ± 0.8 nm on average were successfully fabricated. The size of the resultant ZnO-PVP composite nanofibers was considerably affected by two parameters: the concentrations of zinc acetate and PVP in the precursor solution. The concentration of zinc acetate particularly influenced the diameter distribution of the ZnO-PVP nanofibers. The ZnO-PVP nanofibers could be subsequently converted into ZnO nanofibers of a pure wurtzite phase via calcination in air at 500°C for 2 h.

2D materials with unique opto-electronic properties have shown immense potential for application in organic photovoltaics (OPVs). In this article, we reported a facile and efficient strategy to enhance the device performance of OPVs by doping 2D material of antimonene quantum sheets (AMQSs) into PEDOT:PSS emulsion. The interfacial properties between the hole extraction layer (HEL) and PBDB-T:ITIC-based active layer were properly meliorated, achieving boosted power conversion efficiency (PCE). Results indicate that the introduced AMQSs could help suppress the recombination loss and improve charge extraction efficiency. Over 8.09% enhancement of PCE is observed compared to that of the control cell with pure PEDOT:PSS. This work provides a simple and valid strategy of HEL modification to realize high efficiency OPVs.