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Abstract: Nanocrystalline Bi2WO6 (BWO) with square-plates morphology was prepared by the hydrothermal synthesis in autoclave. Bi(NO3)3·5H2O with (NH4)10W12O41·5H2O was reacted in pH 9 solution at 160°C for 24h, 48h and 72h to yield the resulting Bi2WO6 as a white precipitate. Bi2WO6 was characterized by the field emission scanning electron microscopy with the energy dispersive X-ray spectrometer (FE-SEM–EDS), the X-ray diffractrommeter (XRD), and the high resolution X-ray photoelectron spectroscopy (HR-XPS). The XPS spectra showed a binding energy shift of Bi element, suggesting that the Bi(+3−x) formal oxidation state could be the substoichiometric forms of Bi within the Bi2O2 layer. The photocatalytic activities of the prepared BWO samples were evaluated by the photodegradation of crystal violet (CV) dye under UV-light irradiation (365nm). The intermediates were separated and characterized by HPLC-PDA-ESI/MS techniques and the results indicate that the N-de-methylation with oxidative degradation of the crystal violet dye took place. Based on these intermediates, we propose and discuss the degradation pathways. [Copyright &y& Elsevier]

BiO x Cl y /BiO m Br n /BiO p I q /g-C 3 N 4 was prepared by using the hydrothermal synthesis. The composition and morphologies of the composites were controlled by adjusting the reaction pH value, temperature, and molar ratio. The optimized BiO x Cl y /BiO m Br n /BiO p I q /g-C 3 N 4 photocatalyst increased the rate of photocatalytic conversion from CO 2 to CH 4 to 0.036 μmol g−1 h−1 and these samples were subjected to photocatalytic degradation with CV. The enhanced photocatalytic activity can be attributed to the effective separation of photogenerated carriers driven by the photoinduced potential difference generated at these heterostructure interfaces, the transfer of photogenerated electrons through the g-C 3 N 4 skeleton, and the favorable alignment of the straddling band structure from BiO x Cl y /BiO m Br n /BiO p I q /g-C 3 N 4. [Display omitted] • The quaternary composites were prepared by a simple hydrothermal method. • The first time, CO 2 conversion to CH 4 using Bi 12 O 17 Cl 2 /Bi 5 O 7 Br/Bi 5 O 7 I/g-C 3 N 4. • The quaternary composites exhibit the great photocatalytic activity for CV. • BC1B1I1–10–100-10 wt%C3N4 was 1.8 times higher than the k value of BC1B1I1–10-100. • O 2 −was the major active species, whereas •OH and h+ were the minor ones. [ABSTRACT FROM AUTHOR]

Acid-base bifunctional heterogeneous solid catalysts, known as the active site with base-acid properties, exhibited relatively good performance on the transesterification for soybean oil for green fuel production. We investigated the use of niobium and three alkali metal oxides (Li, Na, and K) as M y NbO X (M = Li, Na, K) composite as acid-base catalysts for biodiesel production. M y NbO X catalysts were prepared using a simple solid-state reaction, mixing, and grinding niobium dioxide with alkali metal carbonates calcined at 800 °C in air for 4 h. XRD, BET, FE-SEM, TEM and TPD techniques were employed for catalysts characterization. The highest biodiesel yield (98.08%) was achieved under the transesterification condition of 65 °C, 6 h, 24 methanol/oil molar ratio and 2 wt% of LiNbO 3 as the catalyst. The results showed that LiNbO 3 could be efficiently reused at least 10 cycles with an insignificant reduction in the biodiesel yield. The physicochemical properties of the biodiesel were further studied and compared with the ASTM and the EN biodiesel specifications. The results showed that the properties of the biodiesel produced complied with the international standard specifications. [Display omitted] • Novel bifunctional heterogeneous catalyst was synthesized for biodiesel production. • LiNbO 3 able to catalyzed esterification & transesterification simultaneously. • Conversion efficiency of soybean oils to biodiesel using LiNbO 3 catalyst can reach 98%. • The conversion efficiency of waste cooking oil to biodiesel with LiNbO 3 was 92%. [ABSTRACT FROM AUTHOR]

The first systematic synthesis of bismuth oxychloride/bismuth oxybromide/graphitic carbon nitride (BiO x Cl y /BiO m Br n /g-C 3 N 4) nano-composites used a controlled hydrothermal method. The structure, morphology and characteristic of BiO x Cl y /BiO m Br n /g-C 3 N 4 photocatalyst were measured by XRD, UV–vis-DRS, FT-IR, FE-TEM, FE-SEM-EDS, PL, BET, HR-XPS and EPR. Under visible light irradiation, the photodegradation activity was evaluated for the decolorization of crystal violet (CV) and 2-hydroxybenzoic acid (2-HBA) in aqueous solution. The catalytic performance showed that, when using sample BB2C1-4-250-30 wt% g-C 3 N 4 composite as a photocatalyst, the best reaction-rate-constant (k) was 0.071 h−1. It was 1.5 times higher than the k value of BB2C1-4-250 as a photocatalyst. From the scavenging effect of various scavengers, the results of EPR showed that reactive OH was the main scavenger, while O 2 − , h+ and 1O 2 were the second scavenger in CV degradation. In this study, a possible photodegradation mechanism was proposed and discussed. In this work, our method of BiO x Cl y /BiO m Br n /g-C 3 N 4 preparation could be used for future mass production and the BiO x Cl y /BiO m Br n /g-C 3 N 4 composite materials could be applied to the environmental pollution control in future. Figure abstract. Schematic diagram of synthesis method and photocatalysis for as-prepared BiO x Cl y /BiO m Br n /g-C 3 N 4 under different conditions. [Display omitted] • This is the first report on a series of BiOCl/BiOBr/g-C 3 N 4 heterojunctions. • BiOCl/BiOBr/g-C 3 N 4 can be prepared via the hydrothermal method. • The efficiency is enhanced apparently for BiOCl/BiOBr/30 wt % g-C 3 N 4. • Photocatalytic mechanism of BiOCl/BiOBr/g-C 3 N 4 was investigated and discussed. • OH plays the major role; O 2 − , 1O 2 and h+ plays the minor in the CV degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] • We successfully prepared eight crystalline phases of bismuth vanadate by applying the hydrothermal method. • m -BiVO 4 exhibits the greatest visible-light-driven photocatalytic activity on the CV of a series bismuth vanadate. • In the degradation reaction, O 2 − was the major active species, whereas OH and h+ were the minor ones. • E g were 2.0–2.3, 2.1–2.2, 2.1–2.3, 2.1–2.2, 2.3–2.5, 2.6, and 2.2–2.6 eV for eight bismuth vanadate, respectively. By applying the hydrothermal method, we successfully prepared bismuth vanadate in a series of crystalline phases. The characteristics of the samples were identified using various techniques, such as scanning electron microscopy–energy-dispersive X-ray spectroscopy, high-resolution transmission electron microscopy, Fourier-transform infrared spectroscopy, high-resolution X-ray photoelectron spectroscopy, diffuse reflectance ultraviolet–visible (UV–vis) spectroscopy, X-ray diffraction, and Brunauer–Emmett–Teller analysis. Consequently, a BiVO 4 series, including monoclinic BiVO 4 (m -BiVO 4), tetragonal BiVO 4 (t -BiVO 4), BiV 1.025 O 4+X , Bi 4 V 2 O 11 , Bi 14 V 5 O 33 , Bi 12 V 2 O 23 , and Bi 9 VO 16 , were effectively prepared using a simple solution-based hydrothermal method. The powder suspension's photocatalytic activity and the solution's crystal violet (CV) concentration were measured through UV–vis spectroscopy. The UV–vis spectra revealed optical band gaps of 2.0–2.3, 2.1–2.2, 2.1–2.3, 2.1–2.2, 2.3–2.5, 2.6, and 2.2–2.6 eV for m -BiVO 4 , t -BiVO 4 , BiV 1.025 O 4+X , Bi 4 V 2 O 11 , Bi 14 V 5 O 33 , Bi 12 V 2 O 23 , and Bi 9 VO 16 , respectively—indicating that they were indirect semiconductors. This study verifies that m -BiVO 4 exhibits the greatest photocatalytic activity and is thus a promising candidate for the use in visible-light–responsive photocatalysts. [ABSTRACT FROM AUTHOR]

Biodiesel is nontoxic and produces little pollution during combustion. It can be used alone or mixed with petroleum diesel as an additive and is a potential alternative fuel. We investigated the use of zirconium dioxide and three alkali metals (Li, Na, and K) for M 2 ZrO 2 (M = Li, Na, K) composites as solid base catalysts for biodiesel production. M 2 ZrO 2 catalysts were prepared using a simple solid-state reaction and by mixing and grinding zirconium dioxide with alkali metals that were calcined at 800 °C in the air for 4 h. The properties of the catalyst were characterized by Field Emission Scanning Electron Microscope (FE-SEM), Brunauer-Emmett-Teller (BET), X-Ray powder diffractometer (XRD), Fourrier Transform Infrared Spectroscopy (FT-IR) and Hammett indicator method, and analyzed the composition of biodiesel by Gas chromatography. The optimum conditions for the process were a Li 2 ZrO 2 calcination temperature of 800 °C for 4 h, a catalyst amount of 6 wt%, a methanol to oil molar ratio of 8:1, and a reaction temperature of 65 °C. The process could transesterify oil into methyl esters at a 98%–99% conversion rate in 2 h for all series. A series of transesterification experiments was conducted to identify the proper operating conditions. The final product met the selected biodiesel fuel properties in accordance with ASTM D6751. [ABSTRACT FROM AUTHOR]

In this study, a series of BiTeX (X = Cl, Br, I) photocatalysts were successfully synthesized via a simple hydrothermal method. The synthesis process involved dissolving BiX 3 and Te powder in toluene to identify the most efficient material for photocatalytic activity. The main objective of this approach is to facilitate the conversion of carbon dioxide into sustainable solar fuels, such as alcohols and hydrocarbons, offering an appealing solution to address environmental concerns and energy crises. The BiTeX photocatalysts demonstrated significant proficiency in converting CO 2 into CH 4 , particularly BiTeCl exhibited a notable photocatalytic conversion rate of up to 0.51 μmolg -1 h -1 . The optimized BiTeX photocatalysts displayed a gradual and selective transition from CO 2 to CH 4 , ultimately producing valuable hydrocarbons (C 2+ ). Furthermore, owing to their ability to reduce CO 2 , these photocatalysts show promise as materials for mitigating environmental pollution., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The extensive consumption of fossil fuels increases CO 2 concentration in the atmosphere, resulting in serious global warming problems. Meanwhile, the problem of water contamination by organic substances is another significant global challenge. We have successfully synthesized ZnGa 1.01 Te 2.13 /g-C 3 N 4 (ZGT/GCN) composites for the first time as effective photocatalysts for both pollutant degradation and CO 2 reduction. ZGT/GCN composites were synthesized by a simple hydrothermal method. The prepared photocatalysts were characterized by XRD, SEM, TEM-EDS, DRS, BET, PL, and XPS. The ZGT/GCN heterojunction exhibited considerably enhanced photocatalytic activity in the degradation of crystal violet (CV) as well as in the photoreduction of CO 2 when compared to pure ZGT and GCN semiconductors. The optimal rate constant for CV degradation was obtained with the ZGT-80%GCN composite (0.0442 h -1 ), which is higher than the constants obtained with individual ZGT and GCN by 7.75 and 1.63 times, respectively. Moreover, the CO 2 reduction yields into CH 4 by ZGT-80%GCN was 1.013 μmol/g in 72 h, which is 1.21 and 1.08 times larger than the yields obtained with ZGT and GCN. Scavenger and ESR tests were used to propose the photocatalytic mechanism of the ZGT/GCN composite as well as the active species in the CV degradation., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

In this paper, silver niobate (AgNbO 3 ) material was synthesized by a solid-state reaction. AgNbO 3 was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), UV-visible diffuse reflectance spectroscopy (DRS), and Brunauer-Emmett-Teller (BET) measurement. The photocatalytic activity of AgNbO 3 was investigated in degradation of sulfamethoxazole (SMX) under visible light, which is a widely used antibiotic with significant threats towards health and aquatic organisms. Persulfate (PS) oxidant was found to improve the efficiency of the proposed photocatalytic removal of SMX by AgNbO 3 . The different operational parameters in the AgNbO 3 /PS/Vis system were investigated. The best photocatalytic performance was achieved with 0.5 g L -1 AgNbO 3 , 1.0 mM PS, and pH = 5.0 as the optimal conditions, achieving 98% of SMX degradation after 8 h of visible-light irradiation. Scavenger and electron spin resonance (ESR) experiments were carried out to identify the major reactive species in the SMX degradation and to propose the photocatalytic mechanism by the AgNbO 3 /PS/Vis system. The photodecomposition was found to be majorly caused by holes and ˙O 2 - species, with ˙OH and SO 4 ˙ - radicals contributing to improve the photocatalytic process. The AgNbO 3 catalyst was stable and reusable with efficient photocatalytic activity in three successive recycling experiments and its XRD patterns remained virtually unchanged. The reported process of PS activation by the AgNbO 3 photocatalyst is promising for visible-light application in remediation of antibiotic-contaminated water., Competing Interests: There is no conflict to declare., (This journal is © The Royal Society of Chemistry.)

In recent years, lithium-containing ceramic materials have attracted considerable research attention as high-temperature adsorbents of carbon dioxide. The recycling of electrode materials from spent lithium-ion batteries for use as photocatalysts in recovering CO 2 and degrading organic pollutants is worthy of exploration. Solid, magnetic ferrite-containing photocatalysts are easily separated from reaction solutions by using magnetic devices. Solid catalysts (e.g., LiFeO 2 , LiFe 5 O 8 , NaFeO 2 , and K 2 Fe 2 O 4 ) were prepared through the calcination of Fe 2 O 3 and M 2 CO 3 . CO 2 was photoreduced and crystal violet (CV) and 2-hydroxybenzoic acid (2-HBA) were photodegraded under visible light irradiation. The optimized K 2 Fe 2 O 4 photocatalyst increased the rate of photocatalytic conversion from CO 2 to methane at 20.9 µmol g -1  h -1 . The catalytic efficiency indicated that the optimized reaction rate constants of CV with LiFeO 2 , NaFeO 2 , and K 2 Fe 2 O 4 were 2.98 × 10 -1 , 5.32 × 10 -1 , and 4.36 × 10 -1  h -1 , respectively. The quenching effect achieved through the use of various scavengers and the electron paramagnetic resonance in CV degradation revealed the substantial contribution of the reactive superoxide anion radical O 2 - and the minor roles of h + and the OH radical. Its usefulness in the synthesis of solid-base catalyst MFeO 2 is promising for environmental control and relevant applications, particularly in solar energy manufacturing., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

A novel lead bismuth oxybromide/graphene oxide (PbBiO 2 Br/GO) composite photocatalyst were prepared using a controlled and nontemplate hydrothermal technique with PbBiO 2 Br and GO as the starting material. The heterojunction photocatalysts were characterized through XRD, FE-SEM-EDS, HR-TEM, XPS, DR-UV-vis, BET, PL, EPR, and UPS. Under the optimal synthesis conditions, the photocatalytic activity of PbBiO 2 Br/GO composites was much higher than that of PbBiO 2 Br. Under 25 °C, 1 atm, and 432-nm visible light irradiation at, the optimized PbBiO 2 Br/GO increased the rate (at 1.913 µmol g -1  h -1 ) of photocatalytic conversion from carbon dioxide (CO 2 ) to methane (CH 4 ). This conversion rate was higher than that of the original PbBiO 2 Br material (0.957 µmol g -1  h -1 ). Therefore, PbBiO 2 Br/GO is superior for CH 4 production and has great potential as CO 2 photoreduction catalysts. In addition, such catalytic performance (when using 0.05 wt%-GO/PbBiO 2 Br composite as a photocatalyst) indicates that the optimal reaction rate constants of crystal violet (CV) and 2-hydroxybenzoic acid (2-HBA) are 0.1278 and 0.0093 h -1 , respectively, which are 1.82 and 1.24 times the reaction rate constant of PbBiO 2 Br as a photocatalyst, respectively. Our findings are useful for PbBiO 2 Br/GO synthesis and in its future environmental applications, particularly in solar fuel manufacture., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Herein, the preparation of numerous bismuth oxychloride/bismuth oxybromide/bismuth oxyiodide/graphene oxide (BiO x Cl y /BiO m Br n /BiO p I q /GO) composites is reported. A facile hydrothermal method was employed to synthesize these photocatalysts, which had various GO contents. A total of 10 bismuth-oxyhalide composites were isolated and characterized using FE-SEM, XRD, FE-TEM, UV-Vis-DRS, FT-IR, EPR, HR-XPS, PL, and BET. The photocatalytic efficiencies of these 10 bismuth-oxyhalide composites were measured under visible-light irradiation by estimating the concentration of 2-hydroxybenzoic acid (HBA) degradation. The findings indicated that the rate constant order of the HBA degradations was BiOCl/BiOBr/BiOI/GO > Bi 3 O 4 Cl/Bi 3 O 4 Br/Bi 4 O 5 I 2 /GO > Bi 12 O 17 Cl 2 /Bi 3 O 4 Cl/Bi 12 O 17 Br 2 / Bi 7 O 9 I 3 /GO > Bi 12 O 17 Cl 2 /BiOBr/BiOI/GO > Bi 12 O 17 Cl 2 /Bi 12 O 17 Br 2 /Bi 7 O 9 I 3 /Bi 5 O 7 I/GO > Bi 3 O 4 Cl/BiOBr/Bi 3 O 4 Br/Bi 4 O 5 I 2  > Bi 3 O 4 Cl/BiOBr/BiOI > BiOCl/BiOBr/BiOI > Bi 12 O 17 Cl 2 /Bi 5 O 7 Br/Bi 5 O 7 I > GO. A maximum rate constant of 0.191 h -1 was reached for BiOCl/BiOBr/BiOI/GO, providing photocatalytic efficiency that was eight times higher than that of composite BiOCl/BiOBr/BiOI. We also proposed a photocatalytic mechanism demonstrating that O 2 - , h ± , OH, and 1 O 2 are all essential for HBA degradation., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Nano to submicron scaled surface possesses excellent biological affinity and several processes have been undertaken to develop titanium implant with specific surface chemical and phase composition and nano-scale features. A simple process was used to modify the nano topographies on a micro-arc-oxidation (MAO) surface which shortens the time for the conventional hydrothermal process (HT). Nano-scaled anatase precipitates on the MAO surface with different crystallinities and morphologies were regulated via microwave-assisted hydrothermal in pure water (MWDD) or in pH conditioned mediums containing calcium and phosphorus ions (MWCP, MWCP9, MWCP11). The surface morphologies and structures were investigated by SEM, XRD, FTIR, and TEM. Anatase crystals as nano-spikes along [001] direction were observed on the surface of the MWDD and MWCP groups. Increasing the pH of the conditioned medium leads the precipitate to lose its crystallinity; the surface of MWCP11 is covered with amorphous anatase which has a 3D nano-sheet architecture. The MW treated surfaces possess superior hydrophilicity can adsorb more proteins (fibronectin and bovine serum albumin), and the osteoblasts-like MG63 cells on these surfaces have higher spreading ratios than on the MAO and HT groups. The cell viabilities in the MW groups were significantly higher than in the MAO and HT groups on the 7th day (P < 0.05), although their cell viabilities were similar on the first day. MWCP and MWCP11 have higher alkaline phosphatase activity on days 7 and 14 compared to other groups (P < 0.05). The MW treatment produces different nanomorphologies on the MAO surface and retains the original micro/submicron pores and surface calcium and phosphorus contents, thus it is expected to promote osseointegration without compromising the bond strength., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Semiconductor photocatalysts that are robust and galvanized by visible light have been increasingly sought after, with lead bismuth oxyhalide (PbBiO 2 X)-which constitutes a perovskite-like semiconductor-receiving vast attention recently. We noted, after a relevant literature survey, that tetragonal lead bismuth oxyiodide/bismuth oxyiodide/graphitic carbon nitride (t-PbBiO 2 I/Bi 5 O 7 I/g-C 3 N 4 )-supported crystal violet (CV) dye photocatalytic degradation under irradiation with visible light has yet to be reported. The current study provides the report of t-PbBiO 2 I/Bi 5 O 7 I/g-C 3 N 4 composite isolation and characterization realized through field-emission scanning electron microscopy-energy-dispersive spectroscopy, X-ray diffraction, high-resolution X-ray photoelectron spectroscopy, transmission electron microscopy, photoluminescence spectroscopy, Brunauer-Emmett-Teller analysis, Fourier-transform infrared spectroscopy, and ultraviolet-visible diffuse reflectance spectroscopy. Catalytic performance observation revealed that using t-PbBiO 2 I/Bi 5 O 7 I/g-C 3 N 4 resulted in an optimal reaction rate constant of 0.3518 h -1 , a derivation exceeding the derivations for the photocatalysts t-PbBiO 2 I, Bi 5 O 7 I, g-C 3 N 4 , and t-PbBiO 2 I/Bi 5 O 7 I by 15, 6.6, 13.1, and 1.4 times, respectively. As demonstrated by the quenching effects associated with diverse scavengers, the electron paramagnetic resonance results revealed reactive O 2 - to have a major role in the CV dye degradation. The paper proposes and also describes possible photodegradation mechanisms. The method that was realized in this study is valuable for PbBiO 2 I/Bi 5 O 7 I/g-C 3 N 4 synthesis and CV dye photocatalytic degradation for future applications in environmental pollution regulation., (Copyright © 2018 Elsevier Inc. All rights reserved.)

This is the first paper to report a series of bismuth oxyfluoride/bismuth oxyiodide (BiO p F q /BiO x I y ) nanocomposites with different F/I molar ratios, pH values, and reaction temperatures that were synthesized through a template-free and controlled hydrothermal method. These nanocomposites were characterized through scanning electron microscope energy dispersive microscopy (SEM-EDS), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier-transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), and diffuse reflectance spectroscopy (DRS). Under visible-light irradiation, the BiO p F q /BiO x I y composites exhibited excellent photocatalytic activities in the degradation of crystal violet (CV) and 2-hydroxybenzoic acid (HBA). The order of rate constants was BiOF/BiOI > BiOI ≫ BiOF. The photocatalytic activity of BiOF/BiOI composites reached a maximum rate constant of 0.2305 h -1 , 1.2 times higher than that of BiOI and 100 times higher than that of BiOF. Thus, the derived BiOF/BiOI is crucial for photocatalytic activity enhancement. After the removal of CV in the third cycle, no apparent deficits in photocatalytic activity were observed, and the observed deficit was 8.2% during the fifth run. Overall, the catalytic activity and stability observed for the proposed composites were determined to be adequate under visible-light irradiation. For various scavengers, the noted quenching effects demonstrated that reactive O 2 - has a notable role in the degradation of the applied CV., (Copyright © 2018 Elsevier Inc. All rights reserved.)

This paper presents an unprecedented systematic synthetic study of a controlled hydrothermal method for the preparation of bismuth oxychloride/bismuth oxybromide/bismuth oxyiodide ternary composites (BiO x Cl y /BiO m Br n /BiO p I q ). The pH, temperature, and KCl:KBr:KI molar ratio for the reactions were adjusted to control the compositions and morphologies of BiO x Cl y /BiO m Br n /BiO p I q composites. Scanning electron microscopy-energy dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction, ultraviolet-visible diffuse reflectance spectroscopy, Brunauer-Emmett-Teller specific surface areas, photoluminescence spectroscopy, and X-ray photoelectron spectroscopy, and electron paramagnetic resonance spectroscopy were applied to the products. The photocatalytic activities of dispersions were examined by monitoring the 2-hydroxybenzoic acid (HBA) and crystal violet concentrations. Various scavengers demonstrated quenching effects. O 2 - was crucial to HBA degradation, whereas h + and OH played minor roles in HBA degradation. This text hypothesizes possible photodegradation mechanisms., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Crystal violet (CV) is applied in daily use mainly as a commercial dye and antimicrobial agent. Waste water containing CV may affect aquatic ecosystems. Riboflavin, also known as vitamin B 2 , is non-toxic and an essential vitamin required for the functions of the human body. Riboflavin is photosensitive to UV and visible light in terms of generating reactive oxygen species. This study investigated the potential application of blue light on riboflavin, so as to come up with an effective way of degrading CV during its treatment. Photosensitivity of CV leading to degradation in the presence of riboflavin was investigated by light intensity, exposure time, and irradiation dosage. The degradation of CV during riboflavin photolysis treatment was studied by a UV/vis spectrometry and chromatography. The effects of CV degradation on microbial viability are relevant when considering the influences on the ecosystem. This study proved that riboflavin photochemical treatment with blue light degrades CV dye by ROS formation. The riboflavin photolysis-treated CV solution appeared to be transparent during conformational transformations of the CV that was rearranged by free radical species generated from riboflavin photolysis. After riboflavin photolysis, colony-forming units (CFUs) were determined for each CV solution. CFU preservation was 85.2% for the CV dissolved riboflavin solution treated with blue light irradiation at 2.0mW/cm 2 for 120min. Degradation of CV by riboflavin photochemical procedures can greatly reduce antimicrobial ability and serve as an environmental friendly waste water treatment method. Our results presented here concerning riboflavin photolysis in degradation of CV provide a novel technique, and a simple and safe practice for environmental decontamination processes., (Copyright © 2017 Elsevier B.V. All rights reserved.)

A series of BiOxCly/BiOmIn composites were prepared using autoclave hydrothermal methods. The composition and morphologies of the BiOxCly/BiOmIn composites were controlled by adjusting the experimental conditions: the reaction pH value, temperature, and KCl/KI molar ratio. The products were characterized using X-ray diffraction, scanning electron microscopy-electron dispersive X-ray spectroscopy, UV-vis diffuse reflectance spectroscopy, Brunauer-Emmett-Teller specific surface areas, cathodoluminescence, high-resolution transmission electron microscopy, and high-resolution X-ray photoelectron spectroscopy. The photocatalytic efficiencies of composite powder suspensions were evaluated by monitoring the crystal violet (CV) concentrations. In addition, the quenching effects of various scavengers indicated that the reactive O2(-) played a major role, and OH or h(+) played a minor role in CV degradation. The intermediates formed during the decomposition process were isolated, identified, and characterized using high performance liquid chromatography-photodiode array-electrospray ionization-mass spectrometry to elucidate the CV decomposition mechanism., (Copyright © 2014 Elsevier B.V. All rights reserved.)

This is a correction to the following paper: Determining the degradation efficiency and mechanisms of ethyl violet using HPLC-PDA-ESI-MS and GC-MS, Wen-Hsin Chung, Chung-Shin Lu, Wan-Yu Lin, Jian-Xun Wang, Chia-Wei Wu, Chiing-Chang Chen, Chemistry Central Journal 2012, 6:63 (30 June 2012).

The purpose of this study is to investigate the cell attachment and viability on the micro-arc oxidization (MAO) microwave/hydrothermal treated titanium surfaces. The MAO samples were microwave irradiated in vessels containing 50 mL of double-distilled water for 30 minutes (MWDD). The immersion solution consisted of 0.05 mM calcium hydroxide and 0.03 mM ammonium dihydrogen phosphate (MWCP), and same solution with the pH value adjusted to 9.6 (MWCP9.6) were compared. The hydrothermal (HT) samples were conducted under DD water at 250°C for 3 hr. The cell viability (WST assay) results show that there was no significant different on the cell viability at 4 hrs. After cultured for 1 day, the cell viability of MG63 cells on the samples from high to low is HT = MWDD = MWCP > MWCP9.6 > MAO. No significant different was found on the cell number between groups. However, the percentages of spreading cells to total adherent cells are higher on the MWDD, MWCP, and MWCP9.6 groups (75.7%, 69.9%, 69.4%, respectively), when compare to MAO and HT groups (48.4% and 41.5%). These results demonstrate that increased cell spreading on a MW groups with submicro-to- nano scale calcium phosphates on titania produced by microwave/hydrothermal process.

Aim: Five representative waterborne pathogens were used to illustrate the relationship between chitosan's antibacterial activity and the surface characteristics of the bacterial cell wall., Methods: Chitosan was prepared with averaged 75% or 95% deacetylated degree to examine its antibacterial activity against waterborne pathogens. Fresh microbial inoculants for the antibacterial assessment were prepared on nutrient agar at 37 degrees for 24 h. The evaluation items of antibacterial mechanism included hydrophilicity and negative charge analysis of cell surface, and adsorptive characteristics of chitosan to bacterial cell. All the experiments were applied in triplicate tests at least., Results: Although cell wall hydrophilicity was similar among Gram-negative bacteria, the distribution of negative charge on their cell surfaces was quite different. More negatively charged cell surfaces had a greater interaction with chitosan, a phenomenon further confirmed by transmission electron micrography (TEM)., Conclusion: Results showed the hydrophilicity in Gram-negative bacteria was much higher than in Gram-positive ones. The correlation coefficient 0.988 between the amount of absorbed chitosan and its inhibition efficiency indicated a close relationship.