The emergence of bismuth molybdate (Bi₂MoO₆) as a promising visible-light catalyst has prompted researchers to increasingly focus on its investigation. To elucidate the impact of different preparation methods on the morphology and photocatalytic properties of Bi₂MoO₆, samples were synthesized via solvothermal, in situ conversion, solution combustion, precipitation, and sol-gel techniques. The physicochemical properties of Bi₂MoO₆ were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), particle size analysis (PSA), fluorescence, and photocurrent measurements. The materials’ ability to degrade Rhodamine B (RhB) was evaluated. The results demonstrated that the crystallinity, morphology, bandgap width, and photogenerated carrier recombination of Bi₂MoO₆ varied significantly depending on the preparation method. Among these methods, the solvothermal route proved most effective, yielding Bi₂MoO₆ with the highest photocatalytic activity, achieving 97.5% RhB degradation within 25 min of light exposure. The low photogenerated carrier recombination rate was attributed to the large specific surface area and narrow bandgap (2.71 eV). This study provides valuable insights into preparing Bi₂MoO₆ with enhanced photocatalytic properties.

The atomic level polishing of a material surface affects the accuracy of devices and the application of materials. Silica slurries play an important role in chemical mechanical polishing (CMP) by polishing the material surface. In this study, an efficient and controllable Stöber approach was developed to synthesize uniform monodisperse silica spheres with different cationic surfactants. The obtained silica spheres exhibited a regular shape with a particle size of 50–150 nm and were distributed evenly and narrowly. The highest surface specific area of the silica spheres was approximately 1155.9 m²/g, which was conducive to the polish process. The monodisperse SiO₂ spheres were applied as abrasives in chemical mechanical polishing. The surface micrographs of silicon wafers during the CMP process were studied using atomic force microscopy (AFM). The results demonstrated that the surface roughness Ra values reduced from 1.07 nm to 0.979 nm and from 1.05 nm to 0.933 nm when using a CTAB-SiO₂ microsphere as an abrasive. These results demonstrate the advantages of monodisperse SiO₂ spheres as abrasive materials in chemical mechanical planarization processes.

The degradation of aquatic pollutants using eco-friendly and non-toxic photocatalytic materials is a pivotal strategy for water pollution remediation. However, single-component photocatalysts typically suffer from low photocatalytic efficiency due to limited light absorption spectra and rapid recombination of photogenerated charge carriers. This study reports a novel and facile one-step mixing strategy for realizing triple synergistic modifications: heterostructured composite construction, specific surface area regulation, and efficient photogenerated electron–hole pair separation of Bi₂MoO₆ (BMO) via composite enhancement with low-cost and intrinsically green g-C₃N₄ (CN), which avoids the high cost, complex processes, and potential pollution risks of precious metal/heavy metal modification for BMO. Under visible-light irradiation, the BMO composite modified with 15 wt% CN achieved a dye removal rate of 85.1% within 60 min, representing a 1.6-fold enhancement in photocatalytic performance compared with that achieved using pristine BMO. We further clarify the unique photocatalytic mechanism of the CN/BMO heterojunction via radical quenching experiments, identifying photogenerated holes (h⁺) and superoxide radicals (·O₂⁻) as the dominant active species for Rhodamine B (RhB) degradation. This study systematically demonstrates a scalable photocatalyst preparation method that integrates controllable specific surface area, rational heterostructure construction, and simple operation, and we provide an in-depth investigation into the photocatalytic reaction process and underlying synergistic enhancement mechanism. The proposed non-metallic modification route provides a new theoretical and experimental basis for the design of high-efficiency BMO-based photocatalysts, and the as-prepared CN/BMO composite holds great potential for practical application in sustainable solar-driven water purification.

The chemical mechanical polishing (CMP) has been widely used for surface modification of critical materials and components and provided global planarization of topography with a low post-planarization slope high quality and efficiency. The colloidal silica slurries play an important role in the finishing processes of optical components. Monodisperse mesoporous silica nanospheres were synthesized with different surfactant by Stöber method. Their architectural features and texture parameters were characterized by XRD, FTIR, N2 adsorption–desorption isotherms, SEM, XPS, and TGA techniques. The spherical SiO2 products presented with the controllable 50-150 nm particle size and distribution. The AFM micrographs reveal that flat and smooth surfaces without distinct scratches residual particles are achieved by using the as-obtained composite particles as abrasives[The particle size of SiO2 slurry plays a critical role in the chemical-mechanical polishing process.

Using bismuth oxide (Bi₂O₃) as the matrix and employing a doping modification strategy to introduce the rare-earth element La, this study prepared La/Bi₂O₃ visible-light-responsive photocatalysts with different doping ratios. The research systematically investigated the regulation mechanisms of La doping on the material’s phase structure, microstructure, band structure characteristics, and visible-light photocatalytic performance. The results indicate that an appropriate amount of La³⁺ equivalently substitutes Bi³⁺ in the lattice, inducing the complete transformation of pure α-Bi₂O₃ into the tetragonal β-Bi₂O₃ phase while maintaining the integrity of the crystal framework. Meanwhile, the modulation of the local electronic structure caused by La³⁺ substitution effectively narrows the bandgap width and broadens the visible-light response range; it also acts as an electron trap to significantly suppress the recombination of photo-generated electron–hole pairs, thereby enhancing charge transport efficiency. Visible-light catalytic degradation experiments confirmed that 4% La/Bi₂O₃ exhibits the optimal degradation kinetics for RhB, achieving a 72.88% degradation rate of Rhodamine B within 60 min of visible-light irradiation. The first-order reaction rate constant was 23 times that of pure Bi₂O₃, and the material demonstrated good stability under repeated cycles. Radical trapping experiments indicated that the order of contribution of active species was ·O₂⁻ > h⁺ > ·OH, with the superoxide radical (·O₂⁻) being the dominant active species. This study confirms that appropriate lattice doping with La can synergistically optimize the structure and optoelectronic properties of Bi₂O₃, providing experimental evidence and theoretical references for the rational design of highly efficient and stable visible-light-responsive Bi₂O₃-based photocatalytic materials.