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In this study, BiOI was successfully synthesized using a hydrothermal method and then modified using hexamethyldisiloxane (HMDS) and polydimethylsiloxane (PDMS), respectively, to achieve a controllable water contact angle (WCA) for these materials. The physical and chemical properties of the modified BiOI were characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) method, UV–Vis diffuse reflectance spectroscopy (DRS), Fourier transform infrared (FTIR) spectroscopy and water contact angle (WCA) techniques. Compared with the unmodified BiOI, HMDS- and PDMS-modified BiOI had higher photocatalytic activities for 17 α -ethinylestradiol (EE2) under visible light irradiation for 28 min after reacting in dark for 30 min. When BiOI was modified using HMDS and PDMS, the WCA increased. When the WCA of HMDS- and PDMS-modified BiOI was controlled in the range of 25.3–32.7 ∘ and 38.1–78.5 ∘ , respectively, better photocatalytic performances were achieved. When the WCA of modified BiOI was 29.7 ∘ (1.00 mL HMDS) and 47.8 ∘ (0.20 mL PDMS), the best photocatalytic performances were achieved with EE2 removal rate of 98.85% and 98.72%, respectively, however, the removal rate of the unmodified BiOI was 85.01%. The reaction rate constants of BiOI (1.00 mL HMDS) and BiOI (0.20 mL PDMS) were 2.33 and 2.15 times higher than the unmodified BiOI, respectively. The improved catalytic performances of modified BiOI could be attributed to the synergistic effect of the controlled wettability of BiOI and functional groups on the surface of photocatalysts. BiOI was modified using HMDS and PDMS, respectively, to achieve a controllable WCA for these materials. Compared with the unmodified BiOI, when the WCA of modified BiOI was 29.7∘ (1.00 mL HMDS) and 47.8∘ (0.20 mL PDMS), the best EE2 removal rates were achieved. The improved catalytic performances of modified BiOI could be attributed to the synergistic effect of the controlled wettability of BiOI and functional groups on the surface of photocatalysts. [ABSTRACT FROM AUTHOR]

In the present work, a direct Z-scheme AgI/BiOBr heterojunction displaying improved photocatalytic activity was designed by a chemical bath deposition method. The obtained photocatalysts were systematically characterized through XRD, SEM, XPS, BET and UV-Vis diffuse reflectance spectroscopy. The synthesized AgI/BiOBr photocatalyst displayed superior photocatalytic performance in the case of 17 α -ethinylestradiol (EE2), where 97.0% compound has been removed within 9 min of irradiation. The rate constant using AgI/BiOBr photo-catalyst was 16.0 and 138.7 times more than that of pure AgI and BiOBr, respectively. Furthermore, the photocatalytic mechanism was investigated. The results of this study indicated that AgI/BiOBr was a stable and efficient photocatalyst, with promising practical applications. The flower-like AgI/BiOBr Z-scheme heterojunction composites were synthesized by using the chemical bath deposition technique. The theoretical and experimental calculations implied that h + , ⋅ O 2 − and ⋅ OH were associated with photocatalysis, and the heterojunction augmented the electron–hole separation and hindered their recombination, resulting in an enhanced photocatalytic performance. The results of this study indicated that AgI/BiOBr was a stable and efficient photocatalyst, with promising practical applications. [ABSTRACT FROM AUTHOR]

17β-estradiol (E2) is one of the environmental endocrine disruptors threatening human health. In this paper, AgI/N-Bi2O3 composites with the different mass ratio of AgI were used to remove E2 in water. The results showed that 40% AgI/N-Bi2O3 composite could degrade E2 by adsorption and photocatalysis synergism: 89% of E2 was adsorbed after 30 min in the dark, and E2 was completely degraded after only 10 min under visible light irradiation. Furthermore, the adsorption process of E2 can be well fitted by the pseudo-second-order kinetic model and the Langmuir model well described the E2 adsorption on the 40% AgI/N-Bi2O3 composite. Finally, the photocatalytic degradation dates were fitted to the pseudo-first-order kinetic model and the possible mechanism of photocatalytic degradation was proposed through the capture experiments of active species and theoretical calculations. [ABSTRACT FROM AUTHOR]

Abstract: A p‐n heterojunction photocatalyst BiOI/Bi5O7I has been synthesized via a mixed solvent method at room temperature. The physical and chemical properties of as‐prepared composites were characterized by XRD, SEM, TEM, XPS, UV‐vis DRS, BET and PL. The photocatalytic performance of BiOI/Bi5O7I composite was evaluated by the photocatalytic decomposition of 17α‐ethinylestradiol (EE2) under visible light irradiation. The results revealed that the BiOI/Bi5O7I composite showed enhanced photocatalytic activity compared to pure BiOI and pure Bi5O7I. The mass ratio of BiOI/Bi5O7I and effect of pH value for photocatalytic activity of BiOI/Bi5O7I composite were investigated. Moreover, the photocatalytic mechanism of the degradation process was thoroughly elucidated. The enhanced photocatalytic performance of the BiOI/Bi5O7I composite should be attributed to fabrication of BiOI/Bi5O7I p‐n heterojunction, which was responsible for efficient separation and transfer of electron‐hole pairs. [ABSTRACT FROM AUTHOR]

In the present work, element modification semiconductor photocatalyst Fe-Bi 2 SiO 5 was successfully synthesized by combining the hydrothermal method and impregnation technique. The obtained photocatalysts were systematically characterized through XRD, SEM, XPS, BET and UV–Vis diffuse reflectance spectroscopy. The synthesized heterojunction Fe/Bi 2 SiO 5 photocatalyst exhibited excellent photocatalytic activity for 17β-Estradiol(E2). While using 20 W mercury lamp as UV light source, the degradation efficiency of E2 by 5% Fe/Bi 2 SiO 5 (the molar ratio of Fe/Bi was 5:100) at 60 min irradiation was 99.5%. The rate constant of E2 degradation on 5% Fe/Bi 2 SiO 5 were about 3.42 times of the P25 and 2.63 times of the pure Bi 2 SiO 5 . The impact of catalyst loading and pH as well as the photocatalytic mechanism was investigated. The possible photocatalytic mechanism has been discussed on the basis of the theoretical calculation and the experimental results. The results of this study indicated that Fe/Bi 2 SiO 5 was a stable and efficient photocatalyst, with promising practical applications. [ABSTRACT FROM AUTHOR]