Triboelectric nanogenerators (TENGs) are emerging devices with the ability to harvest energy in the environment. Natural biomaterials as friction layers for developing the degradable TENG have attracted considerable attention. However, achieving high electrical output performance and degradability simultaneously in a TENG remains challenging. Herein, we obtained a polylactic acid (PLA)/chitosan/cellulose biodegradable materials from natural shrimp shells and seaweed (reusing the wastes) and fabricated the degradable material based TENG (generating electricity without pollution). The open-circuit voltage (V_OC) of TENG can reach 744 V, which is enhanced 65.7% with the addition of 25 wt.% PLA. Meanwhile, a self-powered agriculture protecting system based on the degradable TENG has been constructed, which has a longer working life time (24 days) than similar degradable TENG and a good degradability (complete degradation in soil within 56 days). A suitable working life time not only efficiently promotes seed germination rate of 19%, and eliminates 97% pest eggs as well, achieving multi-functional long-term maintenance. This work provides a new solution to achieve high electrical output performance for degradable TENG, presenting broad and excellent application prospects for different stages of plant growth.

In this study, femtosecond pulsed laser processing was applied to the magnesium alloy, followed by in situ growth of Mg-Al layered double hydroxides (LDHs), and finally modification with low surface energy materials to prepare a biomimetic of centipede-like superhydrophobic composite coating. The resulting biomimetic coating features a dual-scale structure, comprising a micron-scale laser-etched array and nano-scale LDH sheets, which together create a complex hierarchical architecture. The multistage bionic superhydrophobic coating exhibits exceptional corrosion resistance, with a reduction in corrosion current density by approximately five orders of magnitude compared to the bare magnesium alloy substrate. This remarkable corrosion resistance is attributed to the synergistic effects of the superhydrophobicity with a contact angle (CA) of 154.60°, the densification of the surface LDH nanosheets, and the NO₃^- exchange capacity. Additionally, compared to untreated AZ91D alloy, the biomimetic coating prolongs ice formation time by 250% at -40 ℃ and withstands multiple cycles of sandpaper abrasion and repeated tape peeling tests. Furthermore, it demonstrates excellent self-cleaning and anti-fouling properties, as confirmed by dye immersion and dust contamination tests. The construction of the multi-level bionic structured coating not only holds significant practical potential for metal protection but also provides valuable insights into the application of formed LDH materials in functional bionic coating engineering.

Lithium metal is considered as the most promising anode material for the next generation of secondary batteries due to its high theoretical specific capacity and low potential. However, undesirable parasitic reactions, poor cycling stability and safety concerns could be caused by uncontrolled dendrite and high reactivity of Li metal, which hinder the practical application of Li-metal anode in high-energy rechargeable Li metal batteries (LMBs). Here, a facile way is reported to stabilize Li metal anode by building high lithiophilic Mg-Li-Cu alloy. Due to the delocalization of electrons on the deposited lithium enhanced by Cu self-diffusion into Mg-Li alloy, the growth of lithium dendrites could be inhibited by Mg-Li-Cu alloy. Moreover, the parasitic reactions with electrolyte could be avoided by the Mg-Li-Cu alloy anode. It is noteworthy that the symmetric battery life of Mg-Li-Cu alloy electrodes exceeds 9000 h at 1 mA cm⁻² and 1 mAh cm⁻². The full cell (LiFePO₄ || Mg-Li-Cu) exhibits a specific capacity of 148.2 mAh g⁻¹, with a capacity retention of 96.4%, at 1 C after 500 cycles. This work not only pave the way for application of flexible alloy anode in highly stable LMBs, but also provides novel strategies for preparation and optimization of Mg alloy.

Triboelectric nanogenerators (TENG) have emerged as a highly promising energy harvesting technology, attracting significant attention in recent years for their broad applications. Gel-based TENGs, with superior stretchability and sensitivity, have been widely reported as wearable sensors. However, the traditional hydrogel-based TENGs suffer from freezing at low temperatures and drying at high temperatures, resulting in malfunctions. In this study, we introduce an anti-freezing eutectogel, which uses a deep eutectic solvent (DES), to improve the stability and electrical conductivity of TENGs in harsh environmental conditions. The eutectogel-based TENG (E-TENG) produces an open-circuit voltage of 776 V, a short-circuit current of 1.54 µA, and a maximum peak power of 1.1 mW. Moreover, the E-TENG exhibits exceptional mechanical properties with an elongation at a break of 476% under tension. Importantly, it maintains impressive performances across a wide temperature range from −18 to 60 °C, with conductivities of 2.15 S/m at −10 °C and 1.75 S/m at −18 °C. Based on the excellent weight stability of the E-TENG sensor, motion sensing can be achieved in the air, and even underwater. Finally, the versatility of the E-TENG can serve as a wearable sensor, by integrating it with Bluetooth technology. The self-powered E-TENG can monitor various human motion signals in real-time and send the health signals directly to mobile phones. This research paves a new road for the applications of TENGs in harsh environments, offering wireless flexible sensors with real-time health signal monitoring capabilities.

With the growing economy and technology, disease prevention and individual health are becoming more and more important. It is highly urgent to develop a non-toxic, self-powered, and safe high-voltage power source to prevent diseases spread by mosquitoes, especially in isolated or remote areas. Herein, we reported a high-performance rotary triboelectric nanogenerator (R-TENG) based on customized theoretical simulations and a ferroelectric nanocomposite intermediate layer. The customized theoretical simulations based on gradient electrode gaps were established to optimize gap angles and segment numbers of the electrodes, which could prevent air breakdown and enhance the R-TENG output energy by at least 1.5 times. Meanwhile, the electrical output performance of the TENG was further enhanced with a highly oriented BaTiO₃ (BTO) nanoparticles intermediate layer by about 2.5 times. The open-circuit voltage of R-TENG reached more than 6 kV and could continuously light 3420 light-emitting devices (LEDs) or 4 serially connected 36 W household fluorescent lamps. Therefore, a self-powered high-voltage disease prevention system is developed based on the high-performance R-TENG to reduce the risk of disease transmission. This work provides a prospective strategy for the further development of TENGs and expands practical applications of self-powered and high-voltage systems.

Electrochemical corrosion of AZ31 magnesium alloy in the NH₄⁺-SO₄²⁻-Cl⁻ environment is studied. Effect of NH₄⁺ overshadows that of Cl⁻ as the (NH₄)₂SO₄ concentration is 0.005 M or higher, yielding an evolution from localized corrosion to uniform corrosion. Acceleration effect of NH₄⁺ can be attributed to that (ⅰ) NH₄⁺ dissolves the inner MgO and hinders the precipitation of Mg(OH)₂ and (ⅱ) the buffering ability of NH₄⁺ provides H⁺, enhances the hydrogen evolution, and expedites the corrosion process. The latter is demonstrated as the dominant factor with the results in unbuffered and buffered environments. The severe corrosion and hydrogen process in NH₄⁺-containing solution results in a high H_ads coverage and yields an inductive loop within the low frequency. Meanwhile, SO₄²⁻ is helpful in generating cracked but partially protective corrosion products, while Cl⁻ could broaden the corrosion area beneath the corrosion product.