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In this work, efficient catalyst is prepared using ZnO and $\alpha$-Fe₂O₃ along with a surface modification using 2-methylimidazole. Surface modified feature of the catalyst is confirmed by the shifting of vibrational frequency to higher wavenumber. Photocatalytic properties of the as-synthesized and surface modified composites are investigated by measuring the degradation of Methylene Blue (cationic) dye under sunlight irradiation. Both the samples exhibited a similar photocatalytic efficiency of 78% under 300 min. The effect of surface modification shows no significant enhancement on the cationic dye removal. Further, the samples are tested for the degradation of Methyl Blue (anionic) dye in dark condition to validate the effect of functionalization. Surface functionalized sample exhibits 96% efficiency compared to 86% for the pristine sample. Thus, surface modification has extended to be one of the promising techniques for enhancing the catalytic properties of composites.

Ag nanoparticles (Ag NPs) embedded carbon nanofibers (CNFs) were prepared by a new route which included chemical reaction process, electrospinning and calcination technique. The morphology and structure of the composite nanofibers were investigated by scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy and X-ray diffraction. It indicated that Ag NPs were uniformly distributed in the CNFs. This effective synthesis method can be used to prepare other composite nanofibers with functionality. The Ag NPs/CNFs that served as supported catalysts were used in the styrene epoxidation by TBHP. The Ag NPs/CNFs catalyst showed its highly catalytic activity for the epoxidation of styrene (conversion: 40.6%, SO selectivity: 35.9%). This kind of composite nanofiber membrane was proved effectively catalytic activity and recycled easily in the styrene epoxidation.

In this study, porous silica nanoparticles were fabricated in the absence of organic surfactant template at room temperature by a facile one-step dialysis method. By using a dialysis system comprising an ammonia solution as the dialysate, a series of porous silica nanoparticles with a rough surface (e.g., raspberry-like) were obtained by the initiation of a homogeneous ternary tetraethylsilicate-water-ethanol system with different ammonia solution concentrations. The specific surface area and pore volume of porous nanoparticles were regulated by changing the dialysate concentrations. N₂ adsorption–desorption measurements revealed that the porous silica nanoparticles owned both mesopores and micropores and exhibited a type IV isotherm, hence, these nanoparticles can be used as mesoporous silica nanoparticles (MSNs). The Au@MSN nanocomposite can be used as a catalyst for the typical reduction of 4-nitrophenol to 4-aminophenol by NaBH₄ and exhibited excellent catalytic performance.