A flexible zinc ion micro-battery with ultra-high surface capacity (10.1 mA h cm-2) and energy density (8.1 mW h cm-2), as well as good flexibility, is fabricated based on the co-doping effect of V2O5 through an improved 3D printing technology, and is further integrated with flexible solar cells for self-powered wearable electronics.
Abstract Multinary layered 2D nanomaterials can exhibit distinct physicochemical properties and innovative applications as compared to binary 2D nanomaterials due to their unique crystal structures. However, it still remains a challenge for the high‐yield preparation of high‐quality multinary 2D nanosheets. Here, the high‐yield and large‐scale production of two quaternary metal thiophosphate nanosheets are reported, i.e., Ni 3 Cr 2 P 2 S 9 and Ni 3 Cr 2 P 2 Se 9 , via the liquid exfoliation of their layered bulk crystals. The exfoliated single‐crystalline Ni 3 Cr 2 P 2 S 9 nanosheets, with a lateral size ranging from a few hundred nanometers to a few micrometers and thickness of 1.4 ± 0.2 nm, can be easily used to prepare flexible thin films via a simple vacuum filtration process. As a proof‐of‐concept application, the fabricated thin film is used as a supercapacitor electrode with good specific capacitance. These high‐yield, large‐scale, solution‐processable quaternary metal thiophosphate nanosheets could also be promising in other applications like biosensors, cancer therapies, and flexible electronics.
The booming market of portable and wearable electronics has aroused the requests for advanced flexible self-powered energy systems featuring both excellent performance and high safety. Herein, we report a safe, flexible, self-powered wristband system by integrating high-performance zinc-ion batteries (ZIBs) with perovskite solar cells (PSCs). ZIBs were first fabricated on the basis of a defective MnO2–x nanosheet-grown carbon cloth (MnO2–x@CC), which was obtained via the simple lithium treatment of the MnO2 nanosheets to slightly expand the interlayer spacing and generate rich oxygen vacancies. When used as a ZIB cathode, the MnO2–x@CC with a ultrahigh mass loading (up to 25.5 mg cm–2) exhibits a much enhanced specific capacity (3.63 mAh cm–2 at current density of 3.93 mA cm–2), rate performance, and long cycle stability (no obvious degradation after 5000 cycles) than those of the MnO2@CC. Importantly, the MnO2–x@CC-based quasi-solid-state ZIB not only achieves excellent flexibility and an ultrahigh energy density of 5.11 mWh cm–2 (59.42 mWh cm–3) but also presents a high safety under a wide temperature range and various severe conditions. More importantly, the flexible ZIBs can be integrated with flexible PSCs to construct a safe, self-powered wristband, which is able to harvest light energy and power a commercial smart bracelet. This work sheds light on the development of high-performance ZIB cathodes and thus offers a good strategy to construct wearable self-powered energy systems for wearable electronics.
Transition metal dichalcogenide (TMD) nanomaterials, specially MoS2 , are proven to be appealing nanoagents for photothermal cancer therapies. However, the impact of the crystal phase of TMDs on their performance in photoacoustic imaging (PAI) and photothermal therapy (PTT) remains unclear. Herein, the preparation of ultrasmall single-layer MoS2 nanodots with different phases (1T and 2H phase) is reported to explore their phase-dependent performances as nanoagents for PAI guided PTT in the second near-infrared (NIR-II) window. Significantly, the 1T-MoS2 nanodots give a much higher extinction coefficient (25.6 L g-1 cm-1 ) at 1064 nm and subsequent photothermal power conversion efficiency (PCE: 43.3%) than that of the 2H-MoS2 nanodots (extinction coefficient: 5.3 L g-1 cm-1 , PCE: 21.3%). Moreover, the 1T-MoS2 nanodots also give strong PAI signals as compared to negligible signals of 2H-MoS2 nanodots in the NIR-II window. After modification with polyvinylpyrrolidone, the 1T-MoS2 nanodots can be used as a highly efficient agent for PAI guided PTT to effectively ablate cancer cells in vitro and tumors in vivo under 1064 nm laser irradiation. This work proves that the crystal phase plays a key role in determining the performance of nanoagents based on TMD nanomaterials for PAI guided PTT.
Abstract Background Growth differentiation factor 15 (GDF15), a stress‐responsive cytokine from transforming growth factor superfamily, is highly expressed in mammalian tissues, including pancreas, stomach and intestine under pathological conditions. In particular, elevated levels of GDF15 might play an important role in the development and progression of various gastrointestinal cancers (GCs), suggesting its potential as a promising target for disease prediction and treatment. Methods In this review, systematic reviews addressing the role of GDF15 in GCs were updated, along with the latest clinical trials focussing on the GDF15‐associated digestive malignancies. Results The multiple cellular pathways through which GDF15 is involved in the regulation of physiological and pathological conditions were first summarized. Then, GDF15 was also established as a valuable clinical index, functioning as a predictive marker in diverse GCs. Notably, latest clinical treatments targeting GDF15 were also highlighted, demonstrating its promising potential in mitigating and curing digestive malignancies. Conclusions This review unveils the pivotal roles of GDF15 and its potential as a promising target in the pathogenesis of GCs, which may provide insightful directions for future investigations.
Development of reliable glucose sensors for noninvasive monitoring without interruption or limiting users’ mobility is highly desirable, especially for diabetes diagnostic which requires routine/long term monitoring. However, their applications are largely limited by the relatively poor stability. Herein, a porous membrane is synthesized for effective enzymes immobilization and it is robustly anchored to the modified nanotextured electrode solid contacts, so as to realize glucose sensors with significantly enhanced sensing stability and mechanical robustness. To the best of our knowledge, it is the first report on utilizing such nanoporous membranes for electrochemical sensor applications, which eliminates enzymes escaping and provides sufficient surface area for molecular/ion diffusion and interactions, thus to ensure the sustainable catalytic activities of the sensors and generate reliable measureable signals during noninvasive monitoring. The as-assembled nanostructured glucose sensors demonstrates reliable long-term stable monitoring with minimal response drift for up to 20 hours, which delivered a remarkable enhancement. Moreover, they can be integrated into a microfluidic sensing patch for noninvasive sweat glucose monitoring. The as-synthesized nanostructured glucose sensors with remarkable stability can inspire developments of various enzymatic biosensors for reliable noninvasive composition analysis. Besides, in order to realize the ultimate applications of these sensors in predictive clinical diagnostics, personalized healthcare monitoring and chronic diseases management, a self-powered and fully integrated smartwatch in a “smartwatch” fashion was demonstrated. It consists of flexible photovoltaic cells and rechargeable batteries in form of a “watch strap”, electrochemical glucose sensors, customized circuits and display units integrated into a “dial” platform, is successfully fabricated for real-time and continuously monitoring of sweat glucose levels. The functionality of the smartwatch, including sweat glucose sensing, signal processing and display, can be supported with the harvested/converted solar energy without external charging devices. The Zn-MnO 2 batteries serve as intermediate energy storage units and the utilization of aqueous electrolytes eliminated safety concerns for batteries, which is critical for wearable devices. Such a wearable smartwatch realizes integration of energy modules with self-powered capability, electrochemical sensors for noninvasive glucose monitoring, in situ and real-time signals processing/display in a single platform for the first time. The as-fabricated fully integrated and self-powered smartwatch also provides a promising protocol for statistical study and clinical investigation to reveal correlations between sweat compositions and human body dynamics.