The ultrasound-mediated transient materials enable the management of biodegradation processes for implantable electronics.

To prevent surgical site infection (SSI), which significantly increases the rate morbidity and mortality, eliminating microorganisms is prominent. Antimicrobial resistance is identified as a global health challenge. This work proposes a new strategy to eliminate microorganisms of deep tissue through electrical stimulation with an ultrasound (US)‐driven implantable, biodegradable, and vibrant triboelectric nanogenerator (IBV‐TENG). After a programmed lifetime, the IBV‐TENG can be eliminated by provoking the on‐demand device dissolution by controlling US intensity with no surgical removal of the device from the body. A voltage of ≈4 V and current of ≈22 µA generated from IBV‐TENG under ultrasound in vitro, confirming inactivating ≈100% of Staphylococcus aureus and ≈99% of Escherichia coli . Furthermore, ex vivo results show that IBV‐TENG implanted under porcine tissue successfully inactivates bacteria. This antibacterial technology is expected to be a countermeasure strategy against SSIs, increasing life expectancy and healthcare quality by preventing microorganisms of deep tissue.

Direct conversion of mechanical energy into direct current (DC) by triboelectric nanogenerators (TENGs) is one of the desired features in terms of energy conversion efficiency. Although promising applications have been reported using the triboelectric effect, effective DC generating TENGs must be developed for practical purposes. Here, it is reported that continuous DC generation within a TENG itself, without any circuitry, can be achieved by triggering air breakdown via triboelectrification. It is demonstrated that DC generation occurs in combination with i) charge accumulation to generate air breakdown, ii) incident discharge (microdischarge), and iii) conveyance of charges to make the device sustainable. 10.5 mA m−2 of output current and 10.6 W m−2 of output power at 33 MΩ load resistance are achieved. Compared to the best DC generating TENGs ever reported, the TENG in this present study generates about 20 times larger root‐mean square current density.

As vehicles become smarter, an alternative power solution will become increasingly important for future vehicle development. With this context, a triboelectric nanogenerator (TENG) is proposed which fully sits on tires and consists of textile-based tire materials. Both polydimethylsiloxane-coated silver textile, serving as an external tire tread material, and nylon woven textile, serving as an internal tire cord material, performing as opposing triboelectric materials, are well adaptable for rolling tires. It is demonstrated that tire material-based TENG performs at its maximum as it makes mutual contact with the road. The power generation property is characterized under different driving situations such as different tire rotation speeds and varying numbers of devices on the tires. The TENG demonstrates a maximum output voltage and a current of about 225 V and 42 µA, respectively, along with an output power of 0.5 mW at optimum load. The work offers the possibility to not only directly operate minute power-consuming electronics but also collect power and store it while driving a vehicle.

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