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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.

Preparation of functional polyisoprene via direct catalytic insertion polymerization has been preferred because the polymers’ regularity, molar mass and functionality can be facilely controlled by catalyst. However, this method has...

We present experimental and theoretical investigations of the photophysics in the one-dimensional (1D) hybrid organic−inorganic perovskite (HOIP) white-light emitter, [DMEDA]PbBr 4 . It is found that the broadband-emission nature of the 1D perovskite is similar to the case of two-dimensional (2D) HOIP materials, exciton self-trapping (ST) is the dominant mechanism. By comprehensive spectroscopic investigations, we observed direct evidence of exciton crossing the energy barrier separating free and ST states through quantum tunnelling. Moreover, we consider the lattice shrinking mechanisms at low temperatures and interpret the ST exciton formation process using a configuration coordinate diagram. We propose that the energy barrier separating free and ST excitons is temperature-dependent, and consequently, the manner of excitons crossing it is highly dependent on the exciting energy and temperature. For excitons located at the bottom of the free excitonic states, the quantum tunnelling is the dominant channel to the ST states.

W-Cu composite materials are widely used in civilian industries and aerospace fields owing to their integrated properties of high hardness, wear and arc resistance, electrical and thermal conductivities, and low coefficient of thermal expansion. The recently developed submicron-and nanostructured W-Cu composites exhibit superior performance compared to their conventional coarse-grained counterparts and are expected to further expand applications of this group of materials. This review is focused on recent important progress in the preparation, characterization, and mechanical and physical properties of W-Cu composites with refined structures. We summarize the technologies that are capable of refining component structures and evaluate their advantages and limitations. Furthermore, the effects of component refinement and additives such as alloying elements and dispersed particles on the comprehensive performance of W-Cu composites are demonstrated. At the end of the review, we propose potential research issues and directions worthy of attention for the future development of W-Cu composites.

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Rubber industry has been faced with critical challenges including unsustainable fossil-based monomer source, lack of functionality and growing environmental concerns of waste vulcanizates. Development of bio-sourced functional polydienes deems a...

The depletion of fossil based chemicals and the associated pollution have presented huge challenges to sustainability. In this study, we report on bio‐available myrcene participating in copolymerization with isoprene and butadiene by using neodymium catalysts without disruption of the pristine polymer's properties. Efficient incorporation of myrcene into the copolymer was achieved with slightly retarded reactivity compared to the reactivities of butadiene and isoprene. Copolymerization of myrcene with hydroxyl myrcene still remained compatible with the catalyst systems when the cocatalyst was fed in excess, resulting in a novel type of full myrcene based functional elastomer. The high cis‐1,4 selectivity of the system maintained the same level as the homopolymerization. Significant affinity to polar substances was deduced from the remarkably reduced water contact angle, a strong indication of good compatibility with reinforcing fillers. All copolymers displayed over 93.2% cis‐1,4 regularity and high molecular weight with narrow Đ. Good resistance to low temperature was also achieved as indicated by the low glass transition temperature for all copolymers. This study verified that myrcene can be used as a sustainable monomer substituent for general diene based elastomer preparation. © 2020 Society of Chemical Industry