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A dye-sensitized visible light photocatalyst-Bi24O31Cl10.

Wang L, Shang J, Hao W, Jiang S, Huang S, Wang T, Sun Z, Du Y, Dou S, Xie T, Wang D, Wang J - Sci Rep (2014)

Bottom Line: Density functional theory calculations reveal that the p-block elements determine the nature of the dispersive electronic structures and narrow band gap in Bi24O31Cl10.Bi24O31Cl10 exhibits excellent visible-light photocatalytic activity towards the degradation of Rhodamine B, which is promoted by dye sensitization due to compatible energy levels and high electronic mobility.In addition, Bi24O31Cl10 is also a suitable photoanode material for dye-sensitized solar cells and shows power conversion efficiency of 1.5%.

View Article: PubMed Central - PubMed

Affiliation: Center of Materials Physics and Chemistry and Department of Physics, Beihang University, Beijing 100191, P. R. China.

ABSTRACT
The p-block semiconductors are regarded as a new family of visible-light photocatalysts because of their dispersive and anisotropic band structures as well as high chemical stability. The bismuth oxide halides belong to this family and have band structures and dispersion relations that can be engineered by modulating the stoichiometry of the halogen elements. Herein, we have developed a new visible-light photocatalyst Bi24O31Cl10 by band engineering, which shows high dye-sensitized photocatalytic activity. Density functional theory calculations reveal that the p-block elements determine the nature of the dispersive electronic structures and narrow band gap in Bi24O31Cl10. Bi24O31Cl10 exhibits excellent visible-light photocatalytic activity towards the degradation of Rhodamine B, which is promoted by dye sensitization due to compatible energy levels and high electronic mobility. In addition, Bi24O31Cl10 is also a suitable photoanode material for dye-sensitized solar cells and shows power conversion efficiency of 1.5%.

No MeSH data available.


(a) Decoloration of RhB over Bi24O31Cl10, BiOCl, Bi2O3 and Ti2-xOx (C/C0-time curve). (b) Apparent rate constant of different samples. (c) UV-Vis diffuse reflectance spectrum of Bi24O31Cl10 submicron platelets. The inset plot indicates that the band gap is 2.8 eV which is derived from diffuse reflectance spectrum. (d) Mott-Schottky plot for Bi24O31Cl10 in 0.1 M Na2SO4 aqueous solution (pH = 7). The flat band potential is determined to be about −0.73 V. Inset shows a schematic diagram of the dye sensitization process in Bi24O31Cl10/RhB. (e) Current density transient with light ON/OFF for Bi24O31Cl10 powders under visible light (λ ≥ 420 nm). (f) Surface photovoltage spectrum of Bi24O31Cl10, which shows the largest photovoltage response in visible-light range.
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f3: (a) Decoloration of RhB over Bi24O31Cl10, BiOCl, Bi2O3 and Ti2-xOx (C/C0-time curve). (b) Apparent rate constant of different samples. (c) UV-Vis diffuse reflectance spectrum of Bi24O31Cl10 submicron platelets. The inset plot indicates that the band gap is 2.8 eV which is derived from diffuse reflectance spectrum. (d) Mott-Schottky plot for Bi24O31Cl10 in 0.1 M Na2SO4 aqueous solution (pH = 7). The flat band potential is determined to be about −0.73 V. Inset shows a schematic diagram of the dye sensitization process in Bi24O31Cl10/RhB. (e) Current density transient with light ON/OFF for Bi24O31Cl10 powders under visible light (λ ≥ 420 nm). (f) Surface photovoltage spectrum of Bi24O31Cl10, which shows the largest photovoltage response in visible-light range.

Mentions: The visible light photocatalytic activity of the Bi24O31Cl10 was evaluated by a standard Rhodamine B (RhB) degradation measurement (Supplementary Figure S3(a) and (b)). In the photocatalytic degradation of RhB, the activities of Bi24O31Cl10, BiOCl, Bi2O3 and N-doped TiO2 are compared in Figure 3(a) and (b). Bi24O31Cl10 catalyst shows higher photo-oxidation activity than BiOCl, Bi2O3, N-doped TiO2. After irradiation for 60 min, the removal ratio on the Bi24O31Cl10 sample reaches 95%, while only 15%, 88% and 70% RhB removal for Bi2O3, BiOCl and N-doped TiO2, respectively. The removal of total organic carbon (TOC) was chosen as a mineralization index to characterize the RhB degradation. The time independence of the TOC data in the RhB solution in the presence of the Bi24O31Cl10 catalyst under visible light irradiation is shown in Supplementary Figure S4. It is observed that 42% of the TOC was eliminated after 105 min of irradiation, indicating that RhB could be mineralized in this process. The durability and stability of the Bi24O31Cl10 were characterized by a cycling test of photodegradation, in which Bi24O31Cl10 demonstrates high photocatalytic activity in five runs (shown in Supplementary Figure S5). XRD patterns of Bi24O31Cl10 collected before and after photodegradation indicate that this compound is very stable during the photocatalytic process (shown in Supplementary Figure S6).


A dye-sensitized visible light photocatalyst-Bi24O31Cl10.

Wang L, Shang J, Hao W, Jiang S, Huang S, Wang T, Sun Z, Du Y, Dou S, Xie T, Wang D, Wang J - Sci Rep (2014)

(a) Decoloration of RhB over Bi24O31Cl10, BiOCl, Bi2O3 and Ti2-xOx (C/C0-time curve). (b) Apparent rate constant of different samples. (c) UV-Vis diffuse reflectance spectrum of Bi24O31Cl10 submicron platelets. The inset plot indicates that the band gap is 2.8 eV which is derived from diffuse reflectance spectrum. (d) Mott-Schottky plot for Bi24O31Cl10 in 0.1 M Na2SO4 aqueous solution (pH = 7). The flat band potential is determined to be about −0.73 V. Inset shows a schematic diagram of the dye sensitization process in Bi24O31Cl10/RhB. (e) Current density transient with light ON/OFF for Bi24O31Cl10 powders under visible light (λ ≥ 420 nm). (f) Surface photovoltage spectrum of Bi24O31Cl10, which shows the largest photovoltage response in visible-light range.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4260216&req=5

f3: (a) Decoloration of RhB over Bi24O31Cl10, BiOCl, Bi2O3 and Ti2-xOx (C/C0-time curve). (b) Apparent rate constant of different samples. (c) UV-Vis diffuse reflectance spectrum of Bi24O31Cl10 submicron platelets. The inset plot indicates that the band gap is 2.8 eV which is derived from diffuse reflectance spectrum. (d) Mott-Schottky plot for Bi24O31Cl10 in 0.1 M Na2SO4 aqueous solution (pH = 7). The flat band potential is determined to be about −0.73 V. Inset shows a schematic diagram of the dye sensitization process in Bi24O31Cl10/RhB. (e) Current density transient with light ON/OFF for Bi24O31Cl10 powders under visible light (λ ≥ 420 nm). (f) Surface photovoltage spectrum of Bi24O31Cl10, which shows the largest photovoltage response in visible-light range.
Mentions: The visible light photocatalytic activity of the Bi24O31Cl10 was evaluated by a standard Rhodamine B (RhB) degradation measurement (Supplementary Figure S3(a) and (b)). In the photocatalytic degradation of RhB, the activities of Bi24O31Cl10, BiOCl, Bi2O3 and N-doped TiO2 are compared in Figure 3(a) and (b). Bi24O31Cl10 catalyst shows higher photo-oxidation activity than BiOCl, Bi2O3, N-doped TiO2. After irradiation for 60 min, the removal ratio on the Bi24O31Cl10 sample reaches 95%, while only 15%, 88% and 70% RhB removal for Bi2O3, BiOCl and N-doped TiO2, respectively. The removal of total organic carbon (TOC) was chosen as a mineralization index to characterize the RhB degradation. The time independence of the TOC data in the RhB solution in the presence of the Bi24O31Cl10 catalyst under visible light irradiation is shown in Supplementary Figure S4. It is observed that 42% of the TOC was eliminated after 105 min of irradiation, indicating that RhB could be mineralized in this process. The durability and stability of the Bi24O31Cl10 were characterized by a cycling test of photodegradation, in which Bi24O31Cl10 demonstrates high photocatalytic activity in five runs (shown in Supplementary Figure S5). XRD patterns of Bi24O31Cl10 collected before and after photodegradation indicate that this compound is very stable during the photocatalytic process (shown in Supplementary Figure S6).

Bottom Line: Density functional theory calculations reveal that the p-block elements determine the nature of the dispersive electronic structures and narrow band gap in Bi24O31Cl10.Bi24O31Cl10 exhibits excellent visible-light photocatalytic activity towards the degradation of Rhodamine B, which is promoted by dye sensitization due to compatible energy levels and high electronic mobility.In addition, Bi24O31Cl10 is also a suitable photoanode material for dye-sensitized solar cells and shows power conversion efficiency of 1.5%.

View Article: PubMed Central - PubMed

Affiliation: Center of Materials Physics and Chemistry and Department of Physics, Beihang University, Beijing 100191, P. R. China.

ABSTRACT
The p-block semiconductors are regarded as a new family of visible-light photocatalysts because of their dispersive and anisotropic band structures as well as high chemical stability. The bismuth oxide halides belong to this family and have band structures and dispersion relations that can be engineered by modulating the stoichiometry of the halogen elements. Herein, we have developed a new visible-light photocatalyst Bi24O31Cl10 by band engineering, which shows high dye-sensitized photocatalytic activity. Density functional theory calculations reveal that the p-block elements determine the nature of the dispersive electronic structures and narrow band gap in Bi24O31Cl10. Bi24O31Cl10 exhibits excellent visible-light photocatalytic activity towards the degradation of Rhodamine B, which is promoted by dye sensitization due to compatible energy levels and high electronic mobility. In addition, Bi24O31Cl10 is also a suitable photoanode material for dye-sensitized solar cells and shows power conversion efficiency of 1.5%.

No MeSH data available.