Hydrogen has garnered considerable attention as a promising energy source for addressing contemporary environmental degradation and energy scarcity challenges. Electrocatalytic water splitting for hydrogen production has emerged as an environmentally friendly and versatile method, offering high purity. However, the development of cost-effective electrocatalytic catalysts using abundant and inexpensive materials is crucial. In this study, we successfully synthesized nitrogen-doped Co₆Mo₆C supported on nitrogen-doped graphene (N-Co₆Mo₆C/NC). The catalyst exhibited high performance and durability in alkaline electrolytes (1.0 M KOH) for hydrogen evolution, showcasing an overpotential of 185 mV at a current density of 100 mA cm⁻² and a Tafel slope of 80 mV dec⁻¹. These findings present a novel avenue for the fabrication of efficient bimetallic carbide catalysts.

Understanding the ultrafine substructure in freshly formed Fe-C martensite is the key point to reveal the real martensitic transformation mechanism. As-quenched martensite, whose transformation temperature is close to room temperature, has been investigated in detail by means of transmission electron microscopy (TEM) in this study. The observation results revealed that the freshly formed martensite after quenching is actually composed of ultrafine crystallites with a grain size of 1–2 nm. The present observation result matches well with the suggestion based on X-ray studies carried out one hundred years ago. Such nanocrystals are distributed throughout the entire martensite. The whole martensite shows a uniform contrast under both bright and dark field observation modes, irrespective of what observation directions are chosen. No defect contrast can be observed inside each nanocrystal. However, a body-centered cubic {112}-type twinning relationship exists among the ultrafine α-Fe grains. Such ultrafine α-Fe grains or crystallites are the root cause of the fine microstructure formed in martensitic steels and high hardness after martensitic transformation. The formation mechanism of the ultrafine α-Fe grains in the freshly formed martensite will be discussed based on a new γ → α phase transformation mechanism.

Epoxy coatings are popular due to their strong adhesion, low cost, and superior thermal and electrical insulation. Unfortunately, surface defects in epoxy resin lead to surface cracks, limiting the long-term use of epoxy resin coatings in humid marine environments. In this study, modified kaolin (Kaolin) was added to an epoxy resin (EP) to enhance its corrosion resistance, and a silane coupling agent 3-aminopropyltriethoxysilane (APTES), tetraethyl orthosilicate (TEOS), and 8-hydroxyquinoline (8-HQ) were chosen as modifiers. This resulted in the composite 8-hydroxyquinoline/silica/amino kaolin (8-HQ@SiO2@AK), and the structural makeup, loading, hydrophobic characteristics, surface roughness, and corrosion resistance of 8-HQ@SiO2@AK and 8-hydroxyquinoline/silica/amino kaolin/epoxy resin composite coating (8-HQ@SiO2@AK/EP) was investigated. Based on these findings, the maximum contact angle of the hydrophobic composite coating was 88°, its roughness Ra was 3.09 nm, and the hardness and adhesion were unaltered compared to silica-modified kaolin/epoxy composite coatings (SiO2@AK/EP). The impedance modulus |Z|0.01 Hz of the composite was 3.662×109 Ω • cm2 after 30 days of immersion, which indicated significantly enhanced corrosion resistance.