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Graphite carbon nitride (g-C3N4) is an excellent photocatalytic hydrogen evolution material by water splitting, but enhancing its photocatalytic activity and stability is still a big challenge. In this study, by utilizing the super ability of fullerenes (C60) to attract electrons, we synthesized C60/g-C3N4 photocatalytic composite materials with superior electronic separation efficiency. The addition of C60 greatly improves the photocatalytic hydrogen evolution ability of g-C3N4 for water splitting under visible light radiation. The highest hydrogen evolution amount reached 2268.6 μmol/g over 15 mg/L C60/g-C3N4 after 10 h, which is 50.1× that of g-C3N4 under the same water splitting condition. The hydrogen evolution amount over 15 mg/L C60/g-C3N4 in the 0.2 mol/L K2HPO4 system is 4161 μmol/g, indicating the addition of K2HPO4 boosts the activity of C60/g-C3N4. The apparent quantum yield after 76 h was about 5.8%. The long-term photolysis water reaction for 76 h with rising photocatalytic activity exhibits...

Bi3+-doped Ag/AgCl photocatalytic materials were synthesized using a simple coprecipitation approach. Powder X-ray diffraction analysis revealed that Bi3+ was inserted into the crystal lattice of AgCl to partially replace Ag+, resulting in the contraction of AgCl lattice. Ultraviolet–visible absorption tests showed that the dopant Bi3+ slightly widened the band gap of AgCl as it raised the conduction level. X-ray photoelectron spectroscopy revealed the strong interaction between Bi3+, Ag+, and Cl–, and also showed the presence of abundant Bi3+ on the surface of AgCl particles. Methyl orange (MO) photodegradation experiment showed the photocatalytic activity of the Bi3+-doped Ag/AgCl was significantly dependent on the amount of doped Bi3+. The Bi3+-doped Ag/AgCl (2 wt %) reached the highest activity of 91% after 8 min, while the pure Ag/AgCl degraded only 32% of MO. The degradation rate constant of Bi3+-doped Ag/AgCl was 3.75 times higher than that of pure Ag/AgCl. Electron spin resonance showed that •OH w...

The reaction of alcohols and carboxylic acids catalyzed by acids is the traditional method used to prepare esters in the chemical industry. In this study, we report the synthesis of active graphitic carbon nitride (g-C3N4) that may be used in the one-step reaction between benzaldehyde and alcohol to promote the selective formation of esters under visible light irradiation. Compared with the reaction carried out without illumination, g-C3N4 showed obvious improvements in ester formation. The presence of tin dioxide can also contribute to the formation of esters under visible light irradiation. The use of g-C3N4 for the esterification of various alcohols was explored, and the catalyst showed promising results.

Hexagonal, bullet-like ZnO microstructures and nanorod arrays have been prepared successfully by a simple hydrothermal method without surfactants. The structure and composition of the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectrum (EDS), infrared spectrum (IR), and UV–vis diffusive reflectance spectrum (UV–vis). The as-synthesized bullet-like ZnO has hexagonal microstructures with an average diameter of about 10 μm and a length of 30 μm. The obtained ZnO nanorod arrays are highly oriented. Their average diameter is around 50–100 nm, and their length is about 1 μm. In the present work, the effect of concentration, heating temperature, and time on the morphology of ZnO structures was studied experimentally, and their formation was discussed in detail. The photocatalytic degradation of methylene blue (MB) was also investigated.

Perfect, sectorial, and branched Sb2O3 microstructures (st-Sb2O3) were synthesized using a hydrothermal method based on a seeded growth procedure. The structure and composition of the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), infrared spectroscopy (IR), UV–vis diffusive reflectance spectroscopy (UV–vis), and photoluminescence (PL) spectroscopy. SEM images show that the st-Sb2O3 microstructures consist of several prolate microtubes, and the perimeter of the sectors are around 10–40 μm. The prolate microtubes are approximately 30 μm long and 10 μm wide. The growth of st-Sb2O3 may be controlled by changing the different experimental conditions. The introduction of the seed during the growth process plays an important role in the formation of the microstructures. In addition, the PL spectrum of the st-Sb2O3 microstructures shows a strong fluorescence. The formation mechanism of ...

A series of porous BiOI nanoparticles were successfully synthesized via a hydrothermal process. The BiOI nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and UV–vis absorption/reflection spectroscopy (UV–vis). The results showed that the as-prepared BiOI sonocatalyst generally had flake-like-shaped, porous particles about 100 nm in diameter. The sonocatalytic activity of BiOI was evaluated by the degradation of methylene blue (MB) in aqueous solution under ultrasonic irradiation. The effects of the catalyst dosage and initial MB concentration on the sonocatalytic degradation efficiency of MB were studied. The sonocatalytic degradation kinetics of MB was also investigated. The results showed that the degradation kinetics of MB fitted pseudofirst-order kinetics and the Langmuir–Hinshelwood model.