Wearable Helical Molybdenum Nitride Supercapacitors for Self-Powered Healthcare Smartsensors

Advanced Self-Powered Biofuel Cells with Capacitor and Nanogenerator for Biomarker Sensing

Self-powered biofuel cells (BFCs) have evolved for highly sensitive detection of biomarkers such as noncodon micro ribonucleic acids (miRNAs) in the presence of interfering substrates. Self-charging supercapacitive BFCs for in vivo and in vitro cellular microenvironments represent the most prevalent sensing mechanism for diagnosis. Therefore, self-powered biosensing (SPB) with a capacitor and contact separation with a triboelectric nanogenerator (TENG) offers electrochemical and colorimetric dual-mode detection via improved electrical signal intensity. In this review, we discuss three major components: stretchable self-powered BFC design, miRNA sensing, and impedance spectroscopy. A specific focus is given to 1) assembling of sensors for biomarkers, 2) electrical output signal intensification, and 3) role of supercapacitors and nanogenerators in SPBs. We outline the key features of stretchable SPBs and the sequence of miRNA sensing by SPBs. We have emphasized the need of a supercapacitor and nanogenerator for SPBs in the context of advanced assembly of the sensing unit. Finally, we outline the role of impedance spectroscopy in the detection and estimation of biomarkers. We highlight key challenges in SPBs for biomarker sensing, which needs improved sensing accuracy, integration strategies of electrochemical biosensing for in vitro and in vivo microenvironments, and the impact of miRNA sensing on cancer diagnostics. This article attempts a specific focus on the accuracy and limitations of sensing unit for miRNA biomarkers and associated tool for boosting electrical signal intensity for a potential big step further.

Sputtered binder-free Cu3N electrode materials for high-performance quasi-solid-state asymmetric supercapacitors

Developing high-efficiency electrode materials is of great importance in manufacturing supercapacitor devices with superior electrochemical performance. Herein, we for the first time report a binder-free method for controllable growth of Cu₃N electrode materials via magnetron sputtering for supercapacitor applications. Benefiting from their unique polyhedral structure and good electrical conductivity, Cu₃N electrodes can achieve an areal capacity of 90.7 mC cm^-2 at 1 mA cm^-2 and outstanding cycling stability with a capacity retention of 97.4% after 20 000 cycles. In particular, the assembled Cu₃N//active carbon quasi-solid-state asymmetric supercapacitor can exhibit a maximum energy density of 13.2 μW h cm^-2 and a power density of 4.8 mW cm^-2 with an operating voltage of 1.6 V. These remarkable performances demonstrate the great potential of sputtered Cu₃N electrode materials for future energy storage applications.

Bioelectronic devices for light-based diagnostics and therapies

Light has broad applications in medicine as a tool for diagnosis and therapy. Recent advances in optical technology and bioelectronics have opened opportunities for wearable, ingestible, and implantable devices that use light to continuously monitor health and precisely treat diseases. In this review, we discuss recent progress in the development and application of light-based bioelectronic devices. We summarize the key features of the technologies underlying these devices, including light sources, light detectors, energy storage and harvesting, and wireless power and communications. We investigate the current state of bioelectronic devices for the continuous measurement of health and on-demand delivery of therapy. Finally, we highlight major challenges and opportunities associated with light-based bioelectronic devices and discuss their promise for enabling digital forms of health care.