scholarly journals Comparison of CO2 Reduction Performance with NH3 and H2O between Cu/TiO2 and Pd/TiO2

Molecules ◽  
2021 ◽  
Vol 26 (10) ◽  
pp. 2904
Author(s):  
Akira Nishimura ◽  
Ryouga Shimada ◽  
Yoshito Sakakibara ◽  
Akira Koshio ◽  
Eric Hu
Keyword(s):  
Tio2 Film ◽  
Fine Particles ◽  
Uv Light ◽  
Sol Gel ◽  
Co2 Reduction ◽  
Unit Weight ◽  
Molar Ratio ◽  
Illumination Condition ◽  
Molar Quantity ◽  
The Impact

The aim of this study is to clarify the effect of doped metal type on CO2 reduction characteristics of TiO2 with NH3 and H2O. Cu and Pd have been selected as dopants for TiO2. In addition, the impact of molar ratio of CO2 to reductants NH3 and H2O has been investigated. A TiO2 photocatalyst was prepared by a sol-gel and dip-coating process, and then doped with Cu or Pd fine particles by using the pulse arc plasma gun method. The prepared Cu/TiO2 film and Pd/TiO2 film were characterized by SEM, EPMA, TEM, STEM, EDX, EDS and EELS. This study also has investigated the performance of CO2 reduction under the illumination condition of Xe lamp with or without ultraviolet (UV) light. As a result, it is revealed that the CO2 reduction performance with Cu/TiO2 under the illumination condition of Xe lamp with UV light is the highest when the molar ratio of CO2/NH3/H2O = 1:1:1 while that without UV light is the highest when the molar ratio of CO2/NH3/H2O = 1:0.5:0.5. It is revealed that the CO2 reduction performance of Pd/TiO2 is the highest for the molar ratio of CO2/NH3/H2O = 1:1:1 no matter the used Xe lamp was with or without UV light. The molar quantity of CO per unit weight of photocatalyst for Cu/TiO2 produced under the illumination condition of Xe lamp with UV light was 10.2 μmol/g, while that for Pd/TiO2 was 5.5 μmol/g. Meanwhile, the molar quantity of CO per unit weight of photocatalyst for Cu/TiO2 produced under the illumination condition of Xe lamp without UV light was 2.5 μmol/g, while that for Pd/TiO2 was 3.5 μmol/g. This study has concluded that Cu/TiO2 is superior to Pd/TiO2 from the viewpoint of the molar quantity of CO per unit weight of photocatalyst as well as the quantum efficiency.

scholarly journals Impact of Pd Loading on CO2 Reduction Performance over Pd/TiO2 with H2 and H2O

Molecules ◽  
2020 ◽  
Vol 25 (6) ◽  
pp. 1468
Author(s):  
Akira Nishimura ◽  
Tadaaki Inoue ◽  
Yoshito Sakakibara ◽  
Masafumi Hirota ◽  
Akira Koshio ◽  
...  
Keyword(s):  
Tio2 Film ◽  
Uv Light ◽  
Sol Gel ◽  
Co2 Reduction ◽  
Dip Coating ◽  
Unit Weight ◽  
Molar Ratio ◽  
Illumination Condition ◽  
The Impact ◽  
Lamp Illumination

This study investigated the impact of molar ratio of CO2 to reductants H2O and H2, as well as Pd loading weight on CO2 reduction performance with Pd/TiO2 as the photocatalyst. The Pd/TiO2 film photocatalyst is prepared by the sol-gel and dip-coating process to prepare TiO2 film and the pulse arc plasma method is used to dope Pd on TiO2 film. The prepared Pd/TiO2 film was characterized by SEM, EPMA, STEM, EDS, and EELS. This study also investigated the performance of CO2 reduction under the illumination condition of Xe lamp with or without ultraviolet (UV) light. As a result, it is revealed that when the molar ratio of CO2/H2/H2O is set at 1:0.5:0.5, the best CO2 reduction performance has been obtained under the illumination condition of Xe lamp with and without UV light. In addition, it is found that the optimum Pd loading weight is 3.90 wt%. The maximum molar quantities of CO and CH4 produced per unit weight of photocatalyst are 30.3 μmol/g and 22.1 μmol/g, respectively, for the molar ratio of CO2/H2/H2O = 1:0.5:0.5 under the condition of Xe lamp illumination with UV light. With UV light, C2H4 and C2H6, as well as CO and CH4 are also produced by the Pd/TiO2 film photocatalyst prepared in this study.

scholarly journals The Impact of Amount of Cu on CO2 Reduction Performance of Cu/TiO2 with NH3 and H2O

Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 610
Author(s):  
Akira Nishimura ◽  
Yoshito Sakakibara ◽  
Akira Koshio ◽  
Eric Hu
Keyword(s):  
Tio2 Film ◽  
Uv Light ◽  
Sol Gel ◽  
Co2 Reduction ◽  
Dip Coating ◽  
Pulse Number ◽  
Unit Weight ◽  
Molar Ratio ◽  
Light Illumination ◽  
The Impact

This study has investigated the impact of molar ratio of CO2 to reductants NH3 and H2O as well as that of Cu loading on CO2 reduction characteristics over Cu/TiO2. No study to optimize the reductants’ combination and Cu loading weight in order to enhance CO2 reduction performance of TiO2 has been investigated yet. This study prepared Cu/TiO2 film by loading Cu particles during the pulse arc plasma gun process after coating TiO2 film by the sol-gel and dip-coating process. As to loading weight of Cu, it was regulated by change in the pulse number. This study characterized the prepared Cu/TiO2 film by SEM and EPMA. Additionally, the performance of CO2 reduction has been investigated under the illumination condition of Xe lamp with or without ultraviolet (UV) light. It is revealed that the molar ratio of CO2/NH3/H2O is optimized according to the pulse number. Since the amount of H+ which is the same as that of electron is needed to produce CO decided following the theoretical CO2 reduction reacting with H2O or NH3, larger H+ is needed with the increase in the pulse number. It is revealed that Cu of 4.57 wt% for the pulse number of 200 is the optimum condition, whereas the molar quantity of CO per unit weight of Cu/TiO2 with and without UV light illumination is 34.1 mol/g and 12.0 mol/g, respectively.

Synthesis of a novel visible light responsive γ-Fe2O3/SiO2/C-TiO2 magnetic nanocomposite for water treatment

2018 ◽  
Vol 78 (12) ◽  
pp. 2500-2510 ◽  
Author(s):  
Henry H. Mungondori ◽  
Spencer Ramujana ◽  
David M. Katwire ◽  
Raymond T. Taziwa
Keyword(s):  
Water Treatment ◽  
Visible Light ◽  
Surface Area ◽  
Fine Particles ◽  
Uv Light ◽  
Sol Gel ◽  
Spherical Shape ◽  
Solar Irradiation ◽  
Bet Surface Area ◽  
Average Pore

AbstractThis work investigates the preparation of a magnetically recoverable photocatalytic nanocomposite of maghemite nanoparticles coated with silica and carbon doped titanium dioxide. The novel nanocomposite boasts the advantages of efficient photocatalytic degradation of organic pollutants in water and ease of recovery of the fine particles after water treatment. The photocatalytic nanocomposite was successfully synthesized through a stepwise approach via co-precipitation and sol-gel methods. Characterisation by Fourier transform infrared (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) substantiated the existence of the intended structure of the nanocomposite and the particles were found to be in the size range of 15–22 nm with a quasi-spherical shape. Brunauer–Emmett–Teller (BET) surface area analysis revealed an average surface area of 55.20 m2/g, which is higher than that of commercial TiO2 (Degussa P25, 50.00 m2/g), and an average pore diameter of 8.36 nm. A 5 ppm methylene blue solution was degraded with an efficiency of 96.8% after 3 h of solar irradiation, which was 19.7% greater than using the same photo-catalyst under strict UV light irradiation. Photo-catalysis using these nanoparticles was observed to be very effective. The prepared novel visible light active nanocomposite has great potential for incorporation into water treatment systems because it exhibits good stability and magnetism, as well as high photocatalytic efficiency.

N-Doped Cu11O2 (VO4)6 Photocatalyst Prepared by Sol-Gel Method

2011 ◽  
Vol 393-395 ◽  
pp. 1287-1290
Author(s):  
Min Wang ◽  
Qiong Liu ◽  
Qi Xing
Keyword(s):  
Uv Light ◽  
Sol Gel ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Photodegradation Rate ◽  
Triclinic Phase ◽  
Synthesized Materials

The N-doped Cu11O2 (VO4)6 photocatalyst was prepared using the sol-gel method. Techniques of X-ray diffraction (XRD), scanning electron microscope (SEM) have been employed to characterize the as-synthesized materials. During liquid phase photocatalytic degradation of Methy lorange(MO) under the UV-light, the as-prepared N-doped Cu11O2 (VO4)6 exhibits higher activity than the pure Cu11O2 (VO4)6 without doped N. It found that the N-doped Cu11O2 (VO4)6 prepared with the molar ratio of citric acid to metal inons be 2:1, N/Cu molar ratio of 12%, pH=7 and calcinated under 500°C for 4 hours was pure triclinic phase. In this conditions, the sample had highest photocatalytic activity with the photodegradation rate was about 94.42% or so in 60min under 20W ultraviolet lamp.

Synthesis Photocatalytic TiO2/ZnO Nanocomposite and Investigation through Anatase, Wurtzite and ZnTiO3 Phases Antibacterial Behaviors

2018 ◽  
Vol 51 ◽  
pp. 69-77 ◽  
Author(s):  
Hanif Mohammadi ◽  
Mohammad Ghorbani
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Antibacterial Activity ◽  
Uv Light ◽  
Sol Gel ◽  
Molar Ratio ◽  
Plate Count ◽  
Gel Method ◽  
Sol Gel Method ◽  
E Coli

Titanium dioxide is prepared by sol gel method from titanium tetraisopropoxide (TTIP) as precursor and likewise zinc oxide is prepared by sol gel method from zinc acetate dehydrate (ZAD) as precursor. The composite sols are prepared in three different molar ratios 90TiO2:10ZnO, 70TiO2:30ZnO and 50TiO2:50ZnO. Thin film deposition is carried out by dip coating technique. Crystal structure, surface morphology and photocatalytic activity of the prepared nanocomposite thin films are investigated. The antibacterial activity of the prepared nanocomposite thin film against E-coli ATCC 25922 bacteria is examined by placing the thin film in standard aqueous E-coli medium under UV light for 1, 2, 3 and 4 hours and then counting the bacteria with Standard Plate Count Agar (SPC) technique. The prepared thin films have shown strong antibacterial activity in the presence of UV light and by increasing the ZnO molar ratio from 10 to 50, antibacterial activity of the thin films decreases because of decreases in the anatase phase of the TiO2. In the dark conditions by increasing the molar ratio of ZnO, the antibacterial activity of the thin films increases and this phenomenon is related to increasing the zinc ions in the thin films.

Effects of Nd Doping on the Photocatalytic Behavior of Cu11O2 (VO4)6

2011 ◽  
Vol 393-395 ◽  
pp. 1181-1184
Author(s):  
Min Wang ◽  
Qiong Liu ◽  
Qi Xing
Keyword(s):  
Photocatalytic Activity ◽  
Uv Light ◽  
Sol Gel ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Photodegradation Rate ◽  
Triclinic Phase ◽  
Degradation Of Methyl Orange ◽  
Scanning Electron

Nd-doped Cu11O2 (VO4)6 photocatalyst was synthesized by complexing Sol-gel method and characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and energy Dispersive X-Ray Spectroscopy(EDX). The photocatalytic activity of Nd-doped Cu11O2 (VO4)6 was evaluated by photocatalytic degradation of methyl orange (MO) solution under UV-light. It revealed that the Nd-doped Cu11O2 (VO4)6 prepared with the molar ratio of citric acid to metal inons be 2:1, Nd/Cu molar ratio of 2%, pH=7 and calcinated under 500°C for 4 hours was pure triclinic phase. In this conditions, the sample had highest photocatalytic activity with the photodegradation rate was about 95.73% or so in 60min under 20W ultraviolet lamp.

The Influence of ZnO Components on the Photocatalytic Activity of Fe3O4-CuO-ZnO Nanocomposites

2015 ◽  
Vol 1123 ◽  
pp. 227-232 ◽  
Author(s):  
Iqriah Kalim Susanto ◽  
Ardiansyah Taufik ◽  
Rosari Saleh
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Diffuse Reflectance Spectroscopy ◽  
Uv Light ◽  
Sol Gel ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Uv Visible

Nanocomposite Fe3O4-CuO-ZnO with different molar ratio of Fe3O4:CuO:ZnO were synthesized using sol-gel method and characterized by X-ray diffraction, energy dispersive X-ray spectroscopy, field emission scanning electron microscope, UV-visible diffuse reflectance spectroscopy and vibrating sample magnetometer. The characterization results manifested that the combination of Fe3O4, CuO and ZnO nanoparticles was successful. The photocatalytic activity of nanocomposite with the molar ratio of 1:1:5 was more effective in the degradation of methylene blue under UV light irradiation than pure Fe3O4, CuO, ZnO. The role of photoactive species involved in the photocatalytic reaction was studied and found that holes play the most important role in photodegradation of methylene blue.

scholarly journals Impact of Overlapping Fe/TiO2Prepared by Sol-Gel and Dip-Coating Process on CO2Reduction

2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Akira Nishimura ◽  
Xuyan Zhao ◽  
Takuya Hayakawa ◽  
Noriaki Ishida ◽  
Masafumi Hirota ◽  
...  
Keyword(s):  
Glass Fiber ◽  
Uv Light ◽  
Sol Gel ◽  
Base Material ◽  
Visible Spectrum ◽  
Dip Coating ◽  
Coating Process ◽  
Illumination Condition ◽  
Base Materials ◽  
Materials Used

Fe-doped TiO2(Fe/TiO2) film photocatalyst was prepared by sol-gel and dip-coating process to extend its photoresponsivity to the visible spectrum. To promote the CO2reduction performance with the photocatalyst, some types of base materials used for coating Fe/TiO2, which were netlike glass fiber and Cu disc, were investigated. The characterization of prepared Fe/TiO2film coated on netlike glass fiber and Cu disc was analyzed by SEM and EPMA. In addition, the CO2reduction performance of Fe/TiO2film coated on netlike glass disc, Cu disc, and their overlap was tested under a Xe lamp with or without ultraviolet (UV) light, respectively. The results show that the concentration of produced CO increases by Fe doping irrespective of base material used under the illumination condition with UV light as well as that without UV light. Since the electron transfer between two overlapped photocatalysts is promoted, the peak concentration of CO for the Fe/TiO2double overlapping is approximately 1.5 times as large as the Fe/TiO2single overlapping under the illumination condition with UV light, while the promotion ratio is approximately 1.1 times under that without UV light.

scholarly journals Preparation of TiO2@ZIF-8 for the removal of As(III) in water

2017 ◽  
Vol 17 (6) ◽  
pp. 1730-1739 ◽  
Author(s):  
Guangpeng Li ◽  
Hui Jiang ◽  
Dan Li ◽  
Tianyu Liao ◽  
Lingling Yuan ◽  
...  
Keyword(s):  
Uv Light ◽  
Removal Rate ◽  
Sol Gel ◽  
Illumination Condition ◽  
Zeolitic Imidazolate Framework ◽  
X Ray ◽  
Uv Light Irradiation ◽  
The Matrix ◽  
Ft Ir ◽  
The Stability

Abstract To remove As(III) in water, the composite material of TiO2@ZIF-8 was prepared by a sol-gel method with zeolitic imidazolate framework-8 (ZIF-8) as the matrix. The structure of TiO2@ZIF-8 was characterized with scanning electron microscopy (SEM), X-ray powder diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). The results indicated that the best loading efficiency of TiO2 on ZIF-8 occurred when it was calcined at 300 °C for 3 h. This material was used to remove As(III) from aqueous solution, and the effect of the initial concentration of As(III), pH, and the illumination condition on the removal of As(III) was investigated. The results showed that the removal rate of As(III) was as high as 100% under a pH of 4–7, an initial As(III) concentration of less than 2 mg/L, and UV-light irradiation for 2 h. The repeated experiments were also performed for the investigation of the stability of TiO2@ZIF-8.

Photocatalytic and Sonophotocatalytic Activity of Magnetic Heterogeneous Fe3O4/TiO2/CuO Catalyst

2016 ◽  
Vol 864 ◽  
pp. 128-133
Author(s):  
Ardiansyah Taufik ◽  
Shofianina Djalaluidin ◽  
Rosari Saleh
Keyword(s):  
Uv Light ◽  
Sol Gel ◽  
Ultrasound Irradiation ◽  
Catalytic Performance ◽  
Light Irradiation ◽  
Molar Ratio ◽  
Ferromagnetic Behavior ◽  
X Ray ◽  
Uv Light Irradiation ◽  
Result Show

Magnetic heterogeneous Fe3O4/TiO2/CuO catalyst were synthesized using sol-gel method. The molar ratio of Fe3O4/TiO2/CuO were varied from 1:1:0.1 until 1:1:5. The all synthesized catalyst were characterized using X-ray Diffraction (XRD), Energy Dispersive X-ray (EDX), Field Emission Scanning Electron Microscope (FE-SEM), and Vibrating Sample Magnetometer (VSM). The result show that the magnetic heterogeneous Fe3O4/TiO2/CuO catalyst exhibit ferromagnetic behavior under room temperature. The catalytic performance were evaluated on the degradation of methylene blue under UV light and combination of ultrasound and UV-light Irradiation. The combination of ultrasound and UV-light irradiation exhibit batter catalytic performance than ultrasound irradiation only. The Magnetic heterogeneous Fe3O4/TiO2/CuO with molar ratio 1:1:0.1 shows highest catalytic performance. The reusability of catalyst were also observed.

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