Preparation and Application of Titanate Nanotubes on Dye Degradation from Aqueous Media by UV Irradiation

Titanate nanotubes were synthesized by a hydrothermal method using commercial TiO2powder and then used as a photocatalyst. The titanate nanotubes were synthesized by varying the hydrothermal temperature from 110°C to 180°C. The morphological changes and phase transformation of the TiO2nanotubes were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The particles’ scattering behavior was investigated by Raman studies, and the surface area of the nanotubes was determined by a Brunauer, Emmett, and Teller (BET) analysis. Comparative studies show that the surface area of nanotubes increases with increasing temperature up to 130°C. The catalytic behavior of the synthesized nanotubes was also studied. The as-prepared titanate nanotubes were applied to methylene blue (MB, an organic dye) degradation in aqueous media by UV irradiation. Approximately 99% of the dye was removed from the aqueous media using 2 g/L titanate nanotube when the initial dye concentration was 9 mg/L. The total irradiation time was 2 h.

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Preparation and Application of Titanate Nanotubes on Methylene Blue Degradation from Aqueous Media

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.117-119.786 ◽

2011 ◽

Vol 117-119 ◽

pp. 786-789 ◽

Cited By ~ 2

Author(s):

Wen Churng Lin ◽

Wein Duo Yang ◽

Zen Ja Chung ◽

Hui Ju Chueng

Keyword(s):

Methylene Blue ◽

Surface Area ◽

Uv Irradiation ◽

Aqueous Media ◽

Hydrothermal Process ◽

Reaction Times ◽

Titanate Nanotubes ◽

Methylene Blue Degradation ◽

Bet Analysis

Titanate nanotubes were synthesized at various hydrothermal temperatures and reaction times by the hydrothermal process and used as photocatalyst. BET analysis was conducted in order to find out the surface area of these as-prepared samples and it was found that the surface area increases with rise in temperature till 130 oC. Synthesized as-prepared titanate nanotubes were applied on methylene blue degradation from aqueous media by UV irradiation. It was observed that dye removes ~99% from the aqueous media at a titanate nanotubes dose of 2 g/L.

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Combination of mesoporous titanium dioxide with MoS2 nanosheets for high photocatalytic activity

Polish Journal of Chemical Technology ◽

10.1515/pjct-2017-0028 ◽

2017 ◽

Vol 19 (2) ◽

pp. 56-60 ◽

Cited By ~ 4

Author(s):

Loghman Karimi

Keyword(s):

Electron Microscopy ◽

Titanium Dioxide ◽

Photocatalytic Activity ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Dye Degradation ◽

Hydrothermal Process ◽

Bet Analysis ◽

Mesoporous Titanium Dioxide

Abstract This study presents a facile approach for the preparation of MoS2 nanosheet decorated by porous titanium dioxide with effective photocatalytic activity. Mesoporous titanium dioxide nanostructures first synthesized by a hydrothermal process using titanium (III) chloride and then the MoS2/TiO2 were prepared through mixing of MoS2 nanosheet with mesoporous titanium dioxide under ultrasonic irradiation. The synthesized nanocomposite was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), and Brunauer-Emmett-Teller (BET) analysis. The results showed that the nanocomposite has mesoporous structure with specific surface area of 176.4 m2/g and pore diameter of 20 nm. The as-prepared MoS2/TiO2 nanocomposites exhibited outstanding photocatalytic activity for dye degradation under sunlight irradiation, which could be attributed to synergistic effect between the molybdenum disulfide nanosheet and mesoporous titanium dioxide. The photocatalytic performance achieved is about 2.2 times higher than that of mesoporous TiO2 alone. It is believed that the extended light absorption ability and the large specific surface area of the 2D MoS2 nanosheets in the nanocomposite, leading to the enhanced photocatalytic degradation activity.

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In Situ Stabilisation of Silver Nanoparticles at Chitosan-Functionalised Graphene Oxide for Reduction of 2,4-Dinitrophenol in Water

Polymers ◽

10.3390/polym13213800 ◽

2021 ◽

Vol 13 (21) ◽

pp. 3800

Author(s):

Rebaone Makaudi ◽

Hugues Kamdem Paumo ◽

Boniface Kamdem Pone ◽

Lebogang Katata-Seru

Keyword(s):

Electron Microscopy ◽

Silver Nanoparticles ◽

Graphene Oxide ◽

Surface Area ◽

Inductively Coupled Plasma ◽

Aqueous Media ◽

Ag Nps ◽

X Ray ◽

Bet Analysis

This investigation reports the in situ growth of silver nanoparticles onto covalently bonded graphene oxide-chitosan, which serve as supported nanocatalysts for the NaBH4 reduction of 2,4-dinitrophenol in aqueous systems. Fumaryl chloride reacted with chitosan in an acidic environment to yield a tailored polymeric material. The latter was, in turn, treated with the pre-synthesised graphene oxide sheets under acidic conditions to generate the GO-functionalised membrane (GO-FL-CS). The adsorption of Ag+ from aqueous media by GO-FL-CS yielded a set of membranes that were decorated with silver nanoparticles (Ag NPs@GO-FL-CS) without any reducing agent. Various analytical tools were used to characterise these composites, including Fourier transform infrared spectroscopy, Brunauer-Emmett-Teller surface area analysis, X-ray diffraction, scanning electron microscopy/energy-dispersive X-ray analysis, inductively coupled plasma-mass spectrometry, and transmission electron microscopy. The silver-loaded materials were further used for the remediation of 2,4-dinitrophenol from aqueous solutions under batch operation. The BET analysis revealed that the functionalisation of GO with chitosan and Ag NPs (average size 20–60 nm) resulted in a three-fold increased surface area. The optimised catalyst (Ag mass loading 16.95%) displayed remarkable activity with an apparent pseudo-first-order rate constant of 13.5 × 10−3 min−1. The cyclic voltammetry experiment was conducted to determine the nitro-conversion pathway. The reusability/stability test showed no significant reduction efficiency of this metal-laden composite over six cycles. Findings from the study revealed that Ag NPs@GO-FL-CS could be employed as a low-cost and recyclable catalyst to convert toxic nitroaromatics in wastewater.

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Synthesis and characterization of micro-nano carbon filler from Jatropha seeds

BioResources ◽

10.15376/biores.15.2.3237-3251 ◽

2020 ◽

Vol 15 (2) ◽

pp. 3237-3251

Author(s):

Perry Law Nyuk Khui ◽

Md. Rezaur Rahman ◽

Sinin Hamdan ◽

Elammaran Jayamani ◽

Muhammad Kusairy Bin Bakri ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Ball Milling ◽

Surface Area ◽

Microwave Pyrolysis ◽

Bet Analysis ◽

Nano Carbon ◽

Jatropha Seeds ◽

Jatropha Seed ◽

Scanning Electron

Biochar was synthesized from biomass (jatropha seeds) through a low microwave pyrolysis temperature of 180 °C with microwave power of 2kW. A ball milling process reduced the jatropha seed biochar size and converted it into micro-nano carbon biofiller. After ball milling, the biochar size was reduced from 1 to 3 mm to the 10 µm to 600 nm range, which is around a 90% reduction in size. Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and Brunauer-Emmett-Teller (BET) analysis were used to determine the jatropha seed biofillers properties with respect to the ball milling processes. BET results revealed increasing surface area from 0.10 to 3.67 m2/g, and EDS results revealed the elemental composition of the jatropha seed biofillers. The carbon mass percentage increased from 72.6 to 81.2%. Both results were after ball milling for 30 hours. The FTIR results revealed an increase in transmittance intensity and some reduction in peaks after ball milling. Production of micro-nano carbon fillers from microwave pyrolysis jatropha seeds biochar are applicable as reinforcement fillers for high strength composite material fabrications. Scanning electron microscopy, EDS, FTIR, and BET analysis results indicated size reduction of the biochar with increased carbon content from 72.6 to 81.2% as surface area increased from 0.10 to 3.67 m2/g after 30 hours of ball milling.

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Hydrothermal Synthesis and Photocatalytic Performance of Barium Carbonate/tin Dioxide Nanoparticles

Micro and Nanosystems ◽

10.2174/1876402913666211110144252 ◽

2021 ◽

Vol 13 ◽

Author(s):

J.F. Huang ◽

F.H. Tao ◽

C.H. Yu ◽

Y.J. Mao ◽

Z.Y. Xue ◽

...

Keyword(s):

Electron Microscopy ◽

Crystal Violet ◽

Tin Dioxide ◽

Photocatalytic Performance ◽

Barium Carbonate ◽

Dye Degradation ◽

Irradiation Time ◽

Diffuse Reflectance Spectrum ◽

Active Species ◽

Crystal Violet Dye

Background: Crystal violet dye is stable and difficult to be biodegraded owing to the existence of the multiple aromatic rings of the crystal violet molecules. Removing crystal violet dye from the wastewater is a major challenge. Objective: The aim of the research is to synthesize barium carbonate/tin dioxide nanoparticles and investigate the photocatalytic performance for the degradation of crystal violet. Methods: Barium carbonate/tin dioxide nanoparticles were synthesized via a facile hydrothermal route without any surfactants. The crystal structure, micro-morphology, size and optical performance of the barium carbonate/tin dioxide nanoparticles were investigated by powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy and solid ultraviolet-visible diffuse reflectance spectrum. Results : The size of the barium carbonate/tin dioxide nanoparticles is 20 nm to 200 nm with the band gap of 3.71 eV. The photocatalytic activity of the barium carbonate/tin dioxide nanoparticles was measured by the photocatalytic degradation of crystal violet. The crystal violet degradation efficiency reaches 92.1% with the ultraviolet-visible irradiation time of 8 h using 10 mg barium carbonate/tin dioxide nanoparticles. The crystal violet degradation ratio increases to 96.1% when the dosage of the barium carbonate/tin dioxide nanoparticles increases to 20 mg/10 mL crystal violet dye solution. Active species capture photocatalytic experiments showed that the holes, hydroxyl radicals and superoxide ion radicals are the main active species. Reusability experiments displayed that the barium carbonate/tin dioxide nanoparticles are stable for the crystal violet dye degradation. Conclusion: The barium carbonate/tin dioxide nanoparticles show good photocatalytic performance toward crystal violet under ultraviolet light irradiation.

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Application of Fibrous TiO2 as a Photocatalyst in Aqueous Media

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.45.951 ◽

2006 ◽

Vol 45 ◽

pp. 951-956

Author(s):

Hidekazu Tanaka ◽

Ikuyo Higashio ◽

Keiichi Watanabe ◽

Yoko Suyama

Keyword(s):

Methylene Blue ◽

Photocatalytic Activity ◽

Catalytic Activity ◽

Specific Surface ◽

Surface Area ◽

Uv Irradiation ◽

Anatase Phase ◽

Aqueous Media ◽

Rutile Phase ◽

High Photocatalytic Activity

Fibrous TiO2 with ca. 0.16 mm in width and 5 - 6 cm in length was prepared by drying a suspension of monodispersed anatase particles at 363 K in air. The TiO2 fibers thus obtained were thermally treated at the temperatures ranging from 363 to 1273 K for 1 h in air. Elevating the treating temperature increases the crystallinity of anatase phase and reduces the specific surface area from 98 to 5 m2/g due to the sintering of particles. The rutile phase appears at 1273 K by transformation of anatase phase. A photocatalytic activity of the fibers was examined by decomposition of methylene blue (MB) in water under UV irradiation centered at 365 nm. The fibers decomposed the MB in aqueous media under UV irradiation, indicating that the fibers possess a high photocatalytic activity. The catalytic activity is considered to be enhanced on increasing the crystallinity of anatase phase, nevertheless, that decreased with generation of rutile phase.

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Obtaining Ultra-High Surface Area TiO2 Nanorods via Hydrothermally Transformation of Elongated Titanate Nanotubes

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.51.13 ◽

2018 ◽

Vol 51 ◽

pp. 13-23 ◽

Cited By ~ 1

Author(s):

Song Dong Yuan ◽

Shi Qiang Chen ◽

Xing Zhu ◽

Peng Xiong ◽

Yan Fei Yang ◽

...

Keyword(s):

Surface Area ◽

Photocatalytic Performance ◽

High Surface ◽

Hydrothermal Process ◽

High Surface Area ◽

Sodium Titanate ◽

Titanate Nanotubes ◽

Ph Values ◽

Preparation Conditions ◽

Bet Analysis

In this paper, a tunable TiO2nanorod cross-link structure with ultra-high surface area (up to 109.81 m2/g) has been successfully prepared via hydrothermally treating elongated sodium titanate nanotubes. XRD, SEM, HRTEM and BET analysis were employed to characterize the morphology and inner structure of the samples. The preparation conditions (the hydrothermal temperatures and the pH values of the solutions) of the obtained TiO2products were systematically studied. The maximum length of nanorod reaches to 1 μm while the lateral size could be limited less than 10 nm. The surface area can be easily tuned by modifying the stirring rate during the hydrothermal process. In addition, the photocatalytic performance of synthesized TiO2nanorods were also measured, and the nanorod structure with ultra-high surface area showed much better photocatalytic activity than the sample produced without stirring process, which can be attributed to the influence of the large difference in specific surface area of the obtained TiO2products.

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Efficient Adsorption of Deoxynivalenol by Porous Carbon Prepared from Soybean Dreg

Toxins ◽

10.3390/toxins13070500 ◽

2021 ◽

Vol 13 (7) ◽

pp. 500

Author(s):

Zhiwei Ying ◽

Di Zhao ◽

He Li ◽

Xinqi Liu ◽

Jian Zhang

Keyword(s):

Electron Microscopy ◽

Specific Surface ◽

Adsorption Capacity ◽

Surface Area ◽

Specific Surface Area ◽

Porous Carbon ◽

Carbon Material ◽

Adsorption Effect ◽

X Ray ◽

Bet Analysis

A novel porous carbon adsorbent for the removal of deoxynivalenol was prepared from soybean dreg (SD). The new material was characterized by scanning electron microscopy equipped with energy dispersive X-ray spectroscopy (SEM-EDS), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) analysis, N2 adsorption/desorption measurement techniques, X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). The specific surface area of the SDB-6-KOH was found to be 3655.95 m2 g−1, the pore volume was 1.936 cm3 g−1 and the average pore size was 2.125 nm. The high specific surface area and effective functional groups of the carbon material promoted the adsorption of deoxynivalenol. By comparing the adsorption effect of SDB-6-X prepared with different activators (X: KOH, K2CO3, KHCO3), SDB-6-KOH had the highest adsorption capacity. The maximum adsorption capacity of SDB-6-KOH to deoxynivalenol was 52.9877 µg mg−1, and the removal efficiency reached 88.31% at 318 K. The adsorption kinetic and isotherm data were suitable for pseudo-second-order and Langmuir equations, and the results of this study show that the novel carbon material has excellent adsorptive ability and, thus, offers effective practical application potential for the removal of deoxynivalenol.

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Rate of decay of specific surface area of snow during isothermal experiments and morphological changes studied by scanning electron microscopy

Canadian Journal of Physics ◽

10.1139/p03-025 ◽

2003 ◽

Vol 81 (1-2) ◽

pp. 459-468 ◽

Cited By ~ 29

Author(s):

L Legagneux ◽

T Lauzier ◽

F Domin ◽

W F Kuhs ◽

T Heinrichs ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Specific Surface ◽

Decay Rate ◽

Surface Area ◽

Specific Surface Area ◽

Morphological Changes ◽

Main Process ◽

Snow Crystals ◽

Scanning Electron

The quantification of the specific surface area (SSA) of snow crystals and of its variation during metamorphism are essential to understand and model the exchange of reactive gases between the snowpack and the atmosphere. Therefore, the decay rate of SSA of five fresh snow samples was studied in the laboratory at 4, 10, and 15°C under isothermal conditions in closed systems. The time-evolution of the snow SSA can in all cases be very well described by an empirical law of the form, SSA = A log(t + Δt) + B, where A, B, and Δt are adjustable parameters. B seems to be closely related to the initial SSA of the snow, and A describes the SSA decay rate. Our preliminary findings at 15°C suggest that a linear relationship exists between A and B, so that it may be possible to predict the decay rate of snow SSA from its initial value. For the first time, images obtained from scanning electron microscopy show that crystal rounding of snow is the main process taking place during isothermal metamorphism. New grain boundaries also form. More surprising, however, was the formation of new basal, prismatic, and pyramidal crystal faces, sometimes with very sharp angles, especially at 15°C. The growth of facets with sharp angles is not fully explained by current theories of snow metamorphism and has not been observed before. PACS Nos.: 68.35Md, 68.37Hk, 81.20Ev, 81.05Rm

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Removal of oil spills by novel developed amphiphilic chitosan-g-citronellal schiff base polymer

Scientific Reports ◽

10.1038/s41598-021-99241-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ahmed Mohamed Omer ◽

Basant Yossry Eweida ◽

Tamer Mahmoud Tamer ◽

Hesham M. A. Soliman ◽

Safaa Mohamed Ali ◽

...

Keyword(s):

Schiff Base ◽

Crude Oil ◽

Adsorption Capacity ◽

Surface Area ◽

Oil Spills ◽

Sea Water ◽

Morphological Changes ◽

Operational Conditions ◽

Bet Analysis ◽

Oil Adsorption

AbstractA novel chitosan grafted citronellal (Ch-Cit) schiff base amphiphilic polymer was developed for the adsorptive removal of oil spills. The chemical structure was verified by FT-IR spectroscopy and 1H NMR spectrometer, while the morphological changes and surface area were investigated by SEM and BET analysis tools. The amphiphilic character of Ch-Cit schiff base was controlled through variation of the grafting percentage (G%) of citronellal from 11 to 61%. Dramatic changes in the ion exchange capacity (IEC), solubility and water uptake profiles were established, while the oil adsorption capacity was founded in direct relation with the G (%) of citronellal. Operational conditions such as oil amount, adsorption time, adsorbent dose and agitation speed were investigated. The developed Ch-Cit schiff base exhibited a higher surface area (115.94 m2/g) compared to neat chitosan (57.78 m2/g). The oil adsorption capacity of the Ch-Cit schiff base was greatly improved by 166% and 120% for light crude and heavy crude oil, respectively. Finally, the adsorption process was optimized using response surface methodology (RSM).The results substantiate that the amphiphilic Ch-Cit schiff base could be efficiently applied as a low-cost oil-adsorbent for the removal of crude oil spills from sea-water surfaces.

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