Soft wearable electronics for underwater applications are of interest, but depend on the development of a waterproof, long-term sustainable power source. In this work, we report a bionic stretchable nanogenerator for underwater energy harvesting that mimics the structure of ion channels on the cytomembrane of electrocyte in an electric eel. Combining the effects of triboelectrification caused by flowing liquid and principles of electrostatic induction, the bionic stretchable nanogenerator can harvest mechanical energy from human motion underwater and output an open-circuit voltage over 10 V. Underwater applications of a bionic stretchable nanogenerator have also been demonstrated, such as human body multi-position motion monitoring and an undersea rescue system. The advantages of excellent flexibility, stretchability, outstanding tensile fatigue resistance (over 50,000 times) and underwater performance make the bionic stretchable nanogenerator a promising sustainable power source for the soft wearable electronics used underwater.

High-entropy alloys have received considerable attention in the field of catalysis due to their exceptional properties. However, few studies hitherto focus on the origin of their outstanding performance and the accurate identification of active centers. Herein, we report a conceptual and experimental approach to overcome the limitations of single-element catalysts by designing a FeCoNiXRu (X: Cu, Cr, and Mn) High-entropy alloys system with various active sites that have different adsorption capacities for multiple intermediates. The electronegativity differences between mixed elements in HEA induce significant charge redistribution and create highly active Co and Ru sites with optimized energy barriers for simultaneously stabilizing OH* and H* intermediates, which greatly enhances the efficiency of water dissociation in alkaline conditions. This work provides an in-depth understanding of the interactions between specific active sites and intermediates, which opens up a fascinating direction for breaking scaling relation issues for multistep reactions.

system (Zhongling Technology, Gihand) through linking between the somatosensory glove and robotic hand. The cryogenic environment was created by dry ice. For real-time energy delivery, SSANF was attached to a deformable robotic arm (Kinova, Jaco2) with luminescence LEDs connected with the output port. A power source with alternating voltage with an amplitude of 7.5 V was connected with the input port. The sizes of SSANFs used in the multifunctional robot system are all in sizes of 300 × 10 × 3.4 mm 3 .

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Room-temperature phosphorescence (RTP) materials are desirable in chemical sensing because of their long emission lifetime and they are free from background autofluorescence. Nevertheless, the achievement of RTP in aqueous solution is still a highly challenging task. Herein, a molten salt method to prepare carbon dot (CD)-based RTP materials is presented by direct calcination of carbon sources in the presence of inorganic salts. The resultant CD composites (CDs@MP) exhibit bright RTP with a quantum yield of 26.4% and a lifetime of 1.28 s, which lasts for about 6 s to the naked eye. Importantly, their aqueous dispersion also has good RTP characteristics. This is the first time that the long-lived CDs@MP with RTP are achieved in aqueous solution owing to the synergistic effect of crystalline confinement and aggregation-induced phosphorescence. Further investigations reveal that three key processes may be responsible for the observed RTP of the composite materials: (1) The rigid crystalline salt shell can preserve the triplet states of CDs@MP in water and suppress the nonradiative deactivation; (2) The addition of high-charge-density metal ions Mg­(II) and phosphorus element in the composite facilitates the singlet-to-triplet intersystem crossing process and enhances the RTP emission; (3) The aggregation of CDs@MP nanocomposites enables the matrix shell to self-assemble into a network, which further improves the rigidity of the shell and prevents the intermolecular motions, hence prolonging the RTP lifetime. The unique RTP feature and good water dispersibility allow the CD-based composite materials to be applicable in detection of temperature and pH in the aqueous phase. Our approach for producing long-lived RTP CDs@MP is effective, simple, and low-cost, which opens a new route to develop RTP materials that are applicable in aqueous solution.

he earliest known case of SARS-CoV-2 infection causing COVID-19 is thought to have occurred on 17 November 2019 (ref. 1 ). As of 3 August 2021, 198.7 million confirmed cases of COVID-19 and 4.2 million deaths have been reported worldwide 2 . As the global scientific community has rallied in a concerted effort to understand SARS-CoV-2 infections, our background knowledge

In this work, a nanogenerator-controlled drug delivery system (DDS) for use in cancer therapy is successfully established. A new magnet triboelectric nanogenerator (MTENG) is fabricated that can guarantee the contact and detach cycle between the two friction layers and effectively increase the TENG output, up to 70 V after implantation. Using a special structural design, without the commonly used spacer, this contacting-mode MTENG can ensure a high and consistent electricity output after encapsulation and implantation. Doxorubicin-(DOX-) loaded red blood cells (RBCs) are employed as the anti-tumor DDS in this study. After DOX loading, the RBC membranes are stable and the self-release is very slow. However, upon electric stimulation from the MTENG, the release of DOX is remarkably increased, and falls back to normal again after the stimulation. Thus a controllable DDS is established. The MTENG-controllable DDS achieves an outstanding killing of carcinomatous cells both in vitro and in vivo at a low DOX dosage. These results demonstrate a prominent therapeutic effect of the MTENGcontrolled DDS for cancer therapy, which is highly promising for application in the clinic.

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