Superhydrophobic surfaces with self-cleaning properties have been developed based on roughness on the micro- and nanometer scales and low-energy surfaces. However, such surfaces are fragile and stop functioning when exposed to oil. Addressing these challenges, here we show an ultrarobust self-cleaning surface fabricated by a process of metal electrodeposition of a rough structure that is subsequently coated with fluorinated metal-oxide nanoparticles. Scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction were employed to characterize the surfaces. The micro- and nanoscale roughness jointly with the low surface energy imparted by the fluorinated nanoparticles yielded surfaces with water contact angle of 164.1° and a sliding angle of 3.2°. Most interestingly, the surface exhibits fascinating mechanical stability after finger-wipe, knife-scratch, sand abrasion, and sandpaper abrasion tests. It is found that the surface with superamphiphobic properties has excellent repellency toward common corrosive liquids and low-surface-energy substances. Amazingly, the surface exhibited excellent self-cleaning ability and remained intact even after its top layer was exposed to 50 abrasion cycles with sandpaper and oil contamination. It is believed that this simple, unique, and practical method can provide new approaches for effectively solving the stability issue of superhydrophobic surfaces and could extend to a variety of metallic materials.

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In a lithium-ion cell, heat generation and temperature evolution during operation pose a significant bearing on the mechanical degradation and cell performance. The thermal implications on the electrode mechano-electrochemical behavior have been elucidated. Crack formation due to diffusion-induced stress in the active particles has been analyzed. Temperature dependence of the mechanophysicochemical parameters has been taken into account. Total amount of diffusion-induced damage has been estimated for different current density, ambient temperature and particle size. For subzero temperatures, adiabatic operation can boost the cell performance significantly. Increased mechanical degradation has been observed for high C-rate and larger particle sizes. Decreasing ambient temperature results in aggravated crack formation resulting in severe capacity loss. However, at subzero temperatures and under high C-rate conditions, significant concentration gradient exists near the active particle peripheral region resulting in reduced damage penetration. The cell performance analysis reveals that the impact of mechanical degradation on the capacity loss is most prominent at subzero temperatures. The effect of cycling shows accelerated damage in the first few cycles followed by a plateau in the damage evolution. Existence of a critical particle size for maximum damage has been suggested which depends significantly on the cell temperature.

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An eco-friendly superhydrophobic conversion coating is fabricated to enhance the corrosion resistance of the AZ31B Mg alloy by combining the deep eutectic solvent pretreatment and electrodeposition. The coral-like micro−nano structure formed by reacting deep eutectic solvent and Mg alloy provides a structural basis for constructing a superhydrophobic coating. Cerium stearate with low surface energy is deposited on the structure, providing the coating's superhydrophobicity and the corrosion inhibition effect. Electrochemical test results demonstrate that the as-prepared superhydrophobic conversion coating (water contact angle at 154.7°) with a 99.68% protection effect significantly improves anticorrosion properties for the AZ31B Mg alloy. The corrosion current density decreases from 1.79 × 10 −4 A•cm −2 of Mg substrate to 5.57 × 10 −7 A•cm −2 of the coated sample. Besides, the electrochemical impedance modulus reaches the value of 1.69 × 10 3 Ω•cm 2 and increases approximately 23 times in magnitude compared with the Mg substrate. Furthermore, the corrosion protection mechanism is attributed to the coupling effect of water-repellency barrier protection and corrosion inhibition, resulting in excellent corrosion resistance. Results demonstrate a promising strategy for the corrosion protection of Mg alloys by replacing the chromate conversion coating with the superhydrophobic coupling conversion coating.