Minjiao Li

Enhanced Photocatalytic Activity of Bi-doped α-Fe2O3

Abstract Bi-doped α-Fe2O3 photocatalysts with different molar ratios of Bi/Fe (1%, 2%, and 3%) were prepared by a facile parallel flow co-precipitation method. The photocatalysts were characterized by Brunauer-Emmett-Teller (BET) method, X-ray diffraction (XRD), UV/Vis diffuse reflectance spectroscopy and scanning electron microscope (SEM). The separation efficiency of photo-generated charges was investigated using benzoquinone (BQ) as scavenger. The effect of Bi doped on the photocatalytic performance was discussed. The results show that Bidoped α-Fe2O3 photocatalyst exhibits higher photocatalytic performance toward decolorization of methyl orange (MO) aqueous solution than pure α-Fe2O3 under both ultraviolet light and simulated solar light irradiation. The optimization of Bi-doped α-Fe2O3 photocatalyst was obtained. The enhanced mechanism was also discussed.

Enhanced photo-induced charge separation and solar-driven photocatalytic performance of Ag/g-C3N4

ABSTRACT In this contribution, Ag-modified g-C3N4 photocatalysts with different Ag loading were prepared by a facile photoreduction method. The photocatalysts prepared were characterized by X-ray diffraction (XRD), inductively coupled plasma (ICP), UV/Vis diffuse reflectance spectroscopy, and surface photovoltage spectroscopy (SPV), respectively. The separation efficiency of photo-induced charge pairs was studied using benzoquinone (BQ) as scavenger. The activities of the photocatalysts were evaluated by decolorization of rhodamine B aqueous solution under simulated solar illumination. Compared to g-C3N4, Ag/g-C3N4 photocatalysts exhibit enhanced photocatalytic performance due to the improved separation efficiency of photo-generated charge pairs.

Photocatalytic Activity of TiO2 Loaded on BaBiO3 Toward Degradation of Gaseous Benzene

TiO2/BaBiO3 composites were prepared through a pore impregnating method and characterized by Brunauer-Emmett-Teller method, X-ray diffraction, UV-Vis diffuse reflectance, and X-ray photoelectron spectroscopic techniques. The composites exhibit higher photocatalytic activity than pure TiO2 toward degradation of gaseous benzene under ultraviolet light irradiation. The effects of TiO2 loading on the photocatalytic activity were investigated and the optimization of the TiO2/BaBiO3 composite was obtained. The enhanced mechanism was also suggested.

Photocatalytic decolorization of methyl orange solution with KIO3

AbstractThe use of azo dyes must be controlled and the sewage must be properly treated before being released into the environment. Thus, it is crucial to develop processes that can destroy these azo dyes completely. It has been reported that a methyl orange (MO) aqueous solution can be effectively decolorized in KIO3 homogeneous system under UV light irradiation. In this study, the kinetics and effects of KIO4, H2O2, K2S2O8, and KBrO3 on the decolorization of MO with KIO3 under UV light irradiation were investigated in detail. The results show the decolorization reaction is a zero-order reaction when the concentration of MO is above 25 mg/L. , , , and H2O2 can greatly inhibit the photocatalytic decolorization reaction of MO. Several observations indicate the photocatalytic decolorization of MO with KIO3 under UV irradiation occurs by attack only. A more detailed mechanism of KIO3 photocatalysis will be further investigated in the near future.

Comparative Investigation of Simulated Solar-driven Photocatalytic Performance of g-C3N4 Prepared by Different Precursors

Abstract g-C3N4 was prepared by heating different precursors. The photocatalysts were characterized by Brunauer- Emmett-Teller (BET) method, X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-Vis diffuse reflectance spectroscopy, particle size analyzer and surface photovoltage (SPV) spectroscopy, respectively. The photocatalytic activities of g-C3N4 prepared by different precursors for decolorization of rhodamine B aqueous solution were evaluated. The results show that g-C3N4 prepared by heating urea exhibits the best photocatalytic activity under simulated solar irradiation, which can be assigned to the relative higher specific surface area, the smaller particle size, the higher separation efficiency of photo-generated charge pairs, the higher adsorption toward rhodamine B aqueous solution.

Enhanced Simulated Sun Light Photocatalytic Activity of α-Fe2O3 Modified g-C3N4 prepared In-situ

Abstract In this paper, α-Fe2O3/g-C3N4 composite photocatalysts were fabricated in-situ by a facile hydrothermal method and characterized by Brunauer-Emmett-Teller (BET) method, X-ray diffraction (XRD), scanning electron microscopy (SEM), UV/Vis diffuse reflectance spectroscopy (DRS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and surface photovoltage spectroscopy (SPS), respectively. The photocatalytic activity of α-Fe2O3/g-C3N4 for decolorization of methyl orange (MO) aqueous solution was evaluated. The results show that α-Fe2O3/g-C3N4 composites exhibit higher photocatalytic performance than the pure g-C3N4 under simulated sun light irradiation. The remarkably increased performance of α-Fe2O3/g-C3N4 in photocatalysis could be attributed to the increased specific surface area, the enhanced light absorbance, the improved separation efficiency of photo-induced charge carriers and the strong interaction between α-Fe2O3 and g-C3N4. The enhanced mechanism was proposed and proven by SPS analysis.

Effect of SiO2 Content on the Catalytic Performance of SiO2-TiO2 Composite Photocatalyst

Abstract SiO2-TiO2 composite photocatalysts were synthesized by sol-gel method with different SiO2 content (mol%). The specific surface area, structure, the band gap, the relative surface hydroxyl content and the photo-induced charge separation rate of the photocatalysts prepared were characterized by Brunauer-Emmett-Teller (BET) method, Xray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV-Vis diffuse reflectance spectroscopy (DRS), and surface photovoltage spectroscopy (SPS), respectively. The results show that the presence of SiO2 increases the specific surface area and the surface hydroxyl content, and influences the separation rate of photoinduced charge. The photocatalytic performance of SiO2-TiO2 for decolorization of methyl orange (MO) aqueous solution was investigated, the results show that SiO2-TiO2 composite photocatalyst with 16.7% SiO2 (mol%) possesses the best photocatalytic activity among the experimented compositions and the underlying mechanisms are discussed.

Enhanced Photocatalytic Activity of Y and Pd-co-doped Bi2O3 Prepared by Parallel Flow Co-precipitation Method

Abstract In this paper, Y and Pd co-doped Bi2O3 photocatalysts with different molar ratios between Y and Pd were prepared by a facile parallel flow co-precipitation method. The photocatalysts prepared were characterized by Brunauer- Emmett-Teller method (BET), X-ray diffraction (XRD), UV/Vis diffuse reflectance spectroscopy (DRS), scanning electron microscope (SEM), and surface photovoltage (SPV). The Y and Pd co-doped Bi2O3 photocatalysts exhibit higher photocatalytic performance towards de-colorization of methyl orange (MO) aqueous solution than undoped Bi2O3 under UV light and simulated sun light irradiation, and the underlying reason is discussed.