Superhydrophobic Au–Zn alloy surfaces have been fabricated successfully on a zinc substrate via chemical substitution deposition and subsequent annealing treatment. The resulting surfaces exhibited remarkable superhydrophobicity with a WCA of 170 ± 2° and a WSA smaller than 1° without any organic modification. The surface morphologies and chemical compositions were investigated using field emission scanning electron microscopy (FESEM), energy-dispersive spectroscopy (EDS), X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), and the surface roughness was analyzed by atomic force microscopy (AFM). The theoretical mechanism for superhydrophobicity and wettability were also analyzed. The surface wettability changed from superhydrophilicity to superhydrophobicity with a stable Cassie–Baxter state via thermal treatment, which caused the generation of Au–Zn alloys (including AuZn₃ and AuZn) and ZnO, and the formation of micro-/nano-binary architectures. The resulting superhydrophobic Au–Zn alloy surfaces exhibited exquisite roll-down, self-cleaning, and excellent anti-corrosion properties, and also had a firm mechanical property about 10 N, and this might have important values for more potential applications. The corrosion current density was reduced by more than 2 orders of magnitude for the resulting superhydrophobic surface in comparison with the untreated zinc surface and this should be ascribed to the contribution of Au–Zn alloys on the surface.

Superhydrophobic coatings on a copper substrate are grown via electrodeposition followed by thermal annealing. The influence of the deposition potential, zinc ion concentration, deposition time, annealing temperature and annealing time on the wetting properties was systematically investigated. The coating electrodeposited at −1.35 V for 25 min and annealed at 190 °C for 60 min exhibited excellent superhydrophobicity with a contact angle as high as 170 ± 2° and a sliding angle of almost 0°. The water drop can fully bounce as a balloon when impinging such a solid surface, exhibiting excellent non-sticking properties. By adopting various characterization methods, it was demonstrated that the as-prepared superhydrophobic surfaces also exhibited properties of anticorrosion, antiabrasion, long-term stability and durability and large buoyancy force, which offer an effective strategy and promising industrial applications for fabricating superhydrophobic surfaces on various metallic materials.

The morphologies of ZnCo₂O₄ were controlled by an ultrasonic treatment to achieve high-performance supercapacitors.

Fusobacterium nucleatum , a bacterium linked to colorectal cancer, possesses a specific gene called fadA that serves as an early diagnostic biomarker. The CRISPR/Cas12a system has demonstrated marked potential for nucleic acid detection due to its satisfactory selectivity and trans-cleavage ability. However, most CRISPR/Cas-based sensors suffer from problems such as probe entanglement or local aggregation, reducing the Cas enzyme efficiency. In this study, an amplification-free biosensing platform for ultrasensitive detection of F. nucleatum was developed by integrating the highly specific CRISPR/AsCas12a with an improved electrochemiluminescence (ECL) biosensor. Different from the conventional 1- or 2-dimensional probes, the platform was constructed by tetrahedral DNA nanostructure (TDN) probes conjugated with quenchers and coralliform gold (CFAu) functionalized with luminescent agents. The TDN serves as an exceptional scaffold to modulate the recognition unit, substantially enhancing the recognition and cleavage efficiency of AsCas12a toward the probes. Furthermore, the high surface area of CFAu provides extensive landing sites for the luminescent agents, thereby improving the detection sensitivity. The prepared ECL biosensor exhibited a wider linear range (10 fM to 100 nM) and was capable of detecting F. nucleatum down to 1 colony-forming unit/ml. Additionally, the high mismatch sensitivity of AsCas12a to protospacer adjacent motifs and nearby areas provides a strategy for distinguishing mutant from wild-type sequences. Finally, by designing CRISPR RNA (crRNA), this diagnostic method can also be easily modified to detect other bacteria or biomarkers for the early diagnosis of various diseases.

A superhydrophilic surface with a static water contact angle of 4° ± 2° via two-step immersion process and a superhydrophobic surface with a static water contact angle of 169° ± 2° and a sliding angle of almost 0° via successive thermal treatment have been successfully fabricated on aluminum substrates. Surface morphologies and chemical compositions were investigated using field emission scanning electron microscopy, X-ray powder diffraction and X-ray photoelectron spectroscopy, and the formation mechanism was also analyzed. The thermal treatment, which causes the generation of oxides and the appearance of nano-sized particles, is very important for the surface characteristic transformation from superhydrophilicity to superhydrophobicity. The effects of various experimental parameters on wettability, corrosion resistance, anti-icing and deicing properties, stability and large-area preparation were also studied. The corrosion rate of the as-prepared superhydrophobic surface decreases by about 57.6 times compared with that of the untreated aluminum surface and about 34.8 times compared with that of the pure copper surface. These excellent properties of the superhydrophobic surface may be favorable for its potential applications and industrialization.