The extremely large surface area offered by quasi-twodimensional (2D) nanostructures is a great advantage for catalytic applications. While bimetallic materials have been discovered as a group of promising catalysts for electrochemical water splitting, a facile and reliable synthesis approach toward 2D morphology to fully release its electrochemical catalytic potential is still lacking. In this work, bimetallic Co−Mo−O ultrathin nanosheets were synthesized by ionic layer epitaxy with controlled composition ratio. The Co−Mo−O nanosheets exhibited a quadrangle shape with a uniform thickness of ∼2.5 nm. This 2D morphology largely enriched the surface catalytic active site ratio. Particularly, nanosheets with 2:1 Co-to-Mo ratio showed a substantially enhanced OER catalytic activity with a 3 orders of magnitude higher mass activity compared to benchmark IrO 2 and RuO 2 in an alkaline environment. This study introduces a promising possibility for creating high-performance electrocatalysts from 2D bimetallic materials with a high efficiency for material utilization.

Flexible implantable medical devices (IMDs) are an emerging technology that may substantially improve the disease treatment efficacy and quality of life of patients. While many advancements have been achieved in IMDs, the constantly straining application conditions impose extra requirements for the packaging material, which needs to retain both high stretchability and high water resistivity under dynamic strains in a physiological environment. This work reports a polyisobutylene (PIB) blendbased elastomer that simultaneously offers a tissue-like elastic modulus and excellent water resistivity under dynamic strains. The PIB blend is a homogeneous mixture of two types of PIB molecules with distinct molecular weights. The blend achieved an optimal Young's modulus of 62 kPa, matching those of soft biological tissues. The PIB blend film also exhibited an extremely low water permittivity of 1.6−2.9 g m −2 day −1 , from unstrained to 50% strain states. The combination of high flexibility and dynamic water resistivity was tested using triboelectric nanogenerators (TENGs). The PIB blendpackaged TENG was able to stably operate in water for 2 weeks, substantially surpassing the protection offered by Ecoflex. This work offered a promising material solution for packaging flexible IMDs to achieve stable performance in a strained physiological environment.

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Epilepsy is one of the most common neurological disorders that greatly disturb patients’ daily lives. Traditional epileptic diagnosis relies on tedious visual screening by neurologists from lengthy EEG recording that requires the presence of seizure (ictal) activities. We proposed to study automated epileptic diagnosis using interictal EEG data that was much easier to collect than ictal data. The research aims to develop an automated diagnostic system that can use interictal EEG data to diagnose whether the person is epileptic. This system could also test epileptic seizures in order to provide doctors with further tests and potential monitor of patients. To test such a system, we extract power spectral feature, Petrosian fractal dimension, Higuchi fractal dimension and Hjorth parameters for analysis, from which we find our system can be used in patient monitoring(seizure detection) and seizure focus localization, with 98.333% and75.5% accuracy respectively.

In the present study, the heterostructures of ZnO Nanoparticle (NP)/CdS nanowire (NW), SnO2NP/CdS NW, NiS NP/CdS NW, FeS NP/CdS NW, Ag2S NP/CdS NW, and Au NP/CdS NW have been successfully fabricated via the two-stage solvothermal process. Field-emission scan electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) were adopted to characterize the as-prepared products. The optical properties of the as-obtained heterostructures were separately investigated. New insights into understanding and controlling the synthesis of different NW heterostructures are demonstrated in the reliable solvothermal route. We demonstrate that CdS NWs synthesized for 2h are the bifunctional mediator acting as catalyst or active spot for the growth of NW heterostructures Furthermore, understanding and controlling this phenomenon is a great asset for the realization of the formation mechanism of the NW heterostructures and opens up new ways toward for construction of other semiconductor heterostructures with novel properties.