An inverting TENG realizes the AC mode based on triboelectrification and air-breakdown by setting alternating polarity distribution areas, and exhibits unique feature in that both the width ratio and amplitude ratio of AC signals can be tuned.

The use of plastics is resisted worldwide. Therefore, finding alternatives to plastic packaging products is an urgent issue. This work was dedicated to the preparation of biodegradable composited films with potato starch, glycerol, and gelatin. The formulation of the biodegradable film was first optimized via response surface methodology combined with the multi-index comprehensive evaluation method that considered physical properties (thickness, water solution (WS), tensile strength (TS) and elongation at break (E%)) and barrier property (light transmittance (T%)). Results indicated that the optimal conditions were 2.5% starch, 2.0% glycerol, and 1.5% gelatin (based on water). The optimized film presented excellent properties with TS of 4.47 MPa, E% of 109.91%, WS of 43.64%, and T% of 41.21% at 500 nm, and the comprehensive evaluation score of the composite film was 28.68. Moreover, a model verification experiment was further conducted, which proved that the predicted value highly matched experimental values, indicting the credibility and accuracy of the model. The resulting films were further characterized on the basis of rheological measurements, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The rheological measurements proved that the film-forming solution exhibited low shear viscosity and non-Newtonian fluid behavior. FTIR and SEM revealed excellent compatibility among starch, glycerol, and gelatin. Hence, the resulting optimized film may be expected to provide theoretical basis and technical support for the food packing industry.

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Electroosmotic pumps have been widely used in microfluidic systems. However, traditional high‐voltage (HV)‐sources are bulky in size and induce numerous accessional reactions, which largely reduce the system's portability and efficiency. Herein, a motion‐controlled, highly efficient micro‐flow pump based on triboelectricity driven electroosmosis is reported. Utilizing the triboelectric nanogenerator (TENG), a strong electric field can be formed between two electrodes in the microfluidic channel with an electric double layer, thus driving the controllable electroosmotic flow by biomechanical movements. The performance and operation mechanism of this triboelectric electroosmotic pump (TEOP) is systematically studied and analyzed using a basic free‐standing mode TENG. The TEOP produces ≈600 nL min−1 micro‐flow with a Joule heat down to 1.76 J cm−3 nL−1 compared with ≈50 nL min−1 and 8.12 J cm−3 nL−1 for an HV‐source. The advantages of economy, efficiency, portability, and safety render the TEOP a more conducive option to achieve wider applications in motion‐activated micro/nanofluidic transportation and manipulation.