YaBo Zhu

One-pot synthesis of Bi24O31Br10/Bi4V2O11 heterostructures and their photocatalytic properties

Bi24O31Br10/Bi4V2O11 heterojunction photocatalysts were successfully prepared by a facile, one-pot solvothermal method. In the obtained heterojunctions, Bi4V2O11 nanoparticles were uniformly immobilized on or inlaid onto the surfaces of the Bi24O31Br10 nanosheets. They exhibited superior visible light photocatalytic activity towards the degradation of rhodamine B (RhB). Among them, the 25% Bi4V2O11 sample possessed the highest photocatalytic activity, the degradation rate of which was 4 and 6 times as fast as that of bare Bi24O31Br10 and Bi4V2O11, respectively. The enhanced photocatalytic activity could be attributed to the effective separation and transfer of photogenerated carriers. The trapping experiments confirmed that the photogenerated holes and ˙O2− radicals were the main active species responsible for the photodegradation of RhB.

Cadmium sulphide quantum dots sensitized hierarchical bismuth oxybromide microsphere with highly efficient photocatalytic activity.

Cadmium sulphide (CdS) quantum dots (QDs) sensitized that hierarchical bismuth oxybromide (BiOBr) photocatalysts were synthesized via a facile solvothermal approach for the first time, which were characterized by XRD, XPS, SEM, TEM, PL, and UV-vis DRS spectra. The photocatalytic activities were evaluated by the decomposition of methyl orange (MO) under visible light irradiation with commercial TiO(2) Degussa P25 as reference. The results revealed that CdS-BiOBr photocatalysts had strong light absorption in the visible light region compared with pure BiOBr. All CdS-BiOBr photocatalysts possessed higher photocatalytic activity than pure BiOBr and Degussa P25 under the visible light irradiation. The highest activity was obtained by 2%CdS-BiOBr. The enhanced photocatalytic performances were attributed to the matched band potentials of CdS QDs and BiOBr, which resulted in the efficient separation of photogenerated electron-hole pairs. Based on the experimental results, a reasonable photocatalytic mechanism over CdS-BiOBr photocatalysts was proposed. And the photodegradation of MO are associated with ()O(2)(-) radicals and the photogenerated holes on the valance bands of CdS QDs and BiOBr.

One-pot synthesis of Bismuth Oxyhalide/Oxygen-rich bismuth oxyhalide Heterojunction and its photocatalytic activity

BiOBr/Bi24O31Br10 heterojunction photocatalysts were prepared by a facile solvothermal method for the first time. The X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), N2 sorption, UV-vis diffuse reflectance spectroscopy (UV-vis DRS) and photoluminescence (PL) were applied to investigate the structures, morphologies, surface areas and photocatalytic properties of as-prepared samples. The photocatalytic activity of the samples was evaluated by the photocatalytic degradation of Rhodamine B under the visible-light irradiation. The results showed that BiOBr/Bi24O31Br10 heterojunctions with the different Bi24O31Br10 contents could be obtained by simply adjusting the amount of NaOH solution, all of which exhibited enhanced photocatalytic activity compared with bare BiOBr or Bi24O31Br10. Among them, the BiOBr/Bi24O31Br10 heterojunction prepared with 1.5ml of NaOH solution possessed the highest photocatalytic activity. The photogenerated holes and ·O2(-) radicals were confirmed to be the main active species responsible for the photodegradation of RhB. The mechanism of enhanced photocatalytic activity was discussed and the transfer process of the photogenerated charges carrier between BiOBr and Bi24O31Br10 was proposed on the basis of the estimated energy band positions.