Mechanical durability and the triboelectric property of the friction layer are crucial for obtaining stable high power output from triboelectric nanogenerators (TENGs). Here, we introduce butylated melamine formaldehyde (BMF) as a promising triboelectric material because of both its mechanical durability and its highly positive triboelectric property. These unique characteristics originate from its functional group, which contains hydrogen atoms. Kelvin probe force microscopy measurements and density functional theory calculations confirm that BMF is triboelectrically more positive than are pristine MF and methylated MF. In addition, the Young's modulus, calculated by molecular dynamics simulations, of BMF is six times higher than that of polytetrafluoroethylene (PTFE). Additionally, BMF has demonstrated a lower wear rate than PTFE in an abrasion test with Cu as the counter friction material. Because of the superior mechanical and triboelectric characteristics, the root-mean-square output of a rotation-type BMF based TENG [210 V and 125 μA (24 mA m⁻²)] is higher than that of the one with PTFE [90 V and 31 μA (5.9 mA m⁻²)] and remained stable over extended operation of 27 000 cycles. BMF thus offers an opportunity for fabricating high-performance TENGs with applications in self-powered smart systems.

Conventional wound closure techniques, such as suturing and stapling, often cause infection, delayed healing, and tissue damage, particularly in fragile or compromised tissues. A sutureless, battery-free adhesive strip (SBF strip) is developed to integrate shape-memory-assisted mechanical approximation with impedance-matched electrical stimulation for enhanced tissue repair. The device incorporates a shape memory polymer (SMP) responsive at near-body temperature and a robust wet-adhesive interface (> 200 J m⁻²), enabling rapid attachment and uniform closure under mild heating (40 °C). A built-in ultrasound-driven triboelectric system achieves optimal skin-impedance matching (~50 kΩ), generating electric fields up to 0.59 kV m⁻¹ under 0.5 W cm⁻² to promote cellular migration and proliferation. Finite element simulations reveal that SMP-induced contraction redistributes local mechanical strain, reducing scarring. In vivo rat studies demonstrate a 61.7% reduction in scar area compared to sutures, along with improved epithelial regeneration, collagen deposition, and angiogenesis. This mechanically and electrically synergistic platform offers a scalable, battery-free wound therapy strategy, reducing dependence on external power and disposable components while enabling precision-guided healing.

Airborne pathogens retain prolonged infectious activity once attached to the indoor environment, posing a pervasive threat to public health. Conventional air filters suffer from ineffective inactivation of the physics-separated microorganisms, and the chemical-based antimicrobial materials face challenges of poor stability/efficiency and inefficient viral inactivation. We, therefore, developed a rapid, reliable antimicrobial method against the attached indoor bacteria/viruses using a large-scale tunneling charge–motivated disinfection device fabricated by directly dispersing monolayer graphene on insulators. Free charges can be stably immobilized under the monolayer graphene through the tunneling effect. The stored charges can motivate continuous electron loss of attached microorganisms for accelerated disinfection, overcoming the diffusion limitation of chemical disinfectants. Complete (>99.99%) and broad-spectrum disinfection was achieved <1 min of attachment to the scaled-up device (25 square centimeters), reliably for 72 hours at high temperature (60°C) and humidity (90%). This method can be readily applied to high-touch surfaces in indoor environments for pathogen control.

The structural shape of the interface between a metal and dielectric material in a triboelectric nanogenerator (TENG) is an important factor that can improve the device performance. Many interfacial structures have been developed to improve the TENG performance. However, there have been very few studies on the numerical interpretation of various types of contact interfaces. For various interfacial structures on which uniform triboelectric charge density is distributed, the surface charge density (in-plane, out-of-plane, and total) is systematically analyzed to predict the quantity of the transferred charges on the bottom metal under a short-circuit condition. In this work, a numerical study is conducted using a finite element method. The numerical results confirm that the increase in the quantity of the transferred charges collected on the bottom metal via electrostatic induction is related to the increase in the area of the surface structures (i.e., surface enlargement effect due to the formation of complex interfacial morphology). The estimated magnitude of the transferred charges shows the following decreasing trend for the various structural shapes: rectangle > cylinder > pyramid > cone > flat.

We have analytically approximated the triboelectric charge densities generated by triboelectrification reaching equilibrium over time in contact-mode TENG. It is assumed that the surface density of states (SDOS), N_s(E) is constant. The amount of electron transfer at the interface is estimated by calculating the change in vacuum energy level due to the charge density induced in the upper metal electrode and the lower metal electrode within the nanoscale separation range. Numerical results show that N_s(E) and work function difference are dominant compared to dielectric constant (material property) and dielectric thickness (structure parameter).