scholarly journals Evaluation of photocatalytic activities in decomposition of methylene blue in aqueous solution of Mn-ZIF-8 and Mn@Zn

2021 ◽  
Vol 10 (1) ◽  
pp. 116-121
Author(s):  
Hieu Nguyen Trung ◽  
Du Pham Dinh
Keyword(s):  
Heat Treatment ◽  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Uv Radiation ◽  
Treatment Time ◽  
Manganese Content ◽  
Suitable Condition ◽  
High Photocatalytic Activity ◽  
Zeolitic Imidazolate Framework ◽  
Decomposition Efficiency

In the present study, manganese modified zeolitic imidazolate framework-8 (Mn-ZIF-8) and zinc-manganese bimetallic oxides (denoted as Mn@Zn), which was formed by Mn-ZIF-8 heat treatment, had been prepared and applied as photocatalysts to decompose methylene blue (MB) under UV radiation. The influence of manganese content on the structure of ZIF-8, as well as the temperature and heat treatment time of Mn-ZIF-8 material to produce Mn@Zn with high photocatalytic activity was investigated. Results showed that all Mn-ZIF-8 samples have photocatalytic activity, but the MB decomposition efficiency of Mn-ZIF-8 samples were lower than pure ZIF-8. The suitable condition for heat treatment of Mn-ZIF-8 to produce Mn@Zn with high photocatalytic activity was at 500 ºC for 5 hours. However, the MB decomposition efficiency of this sample only reached 22% after 180 minutes of UV radiation.

Facile Preparation of Nanoporous SnO2 for Application in Photodegradation of Methylene Blue

2011 ◽  
Vol 194-196 ◽  
pp. 385-388
Author(s):  
Hong Juan Wang ◽  
Feng Qiang Sun ◽  
Ming Zhong Ren ◽  
Qing Wei Guo
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Photocatalytic Performance ◽  
Uv Light ◽  
High Photocatalytic Activity ◽  
N2 Adsorption ◽  
Photochemical Method ◽  
Degussa P25 ◽  
Adsorption Desorption

Nanoporous SnO2with high photocatalytic activity has been successfully prepared by a photochemical method, using SnCl2aqueous solution as a precursor. The as-synthesized sample was characterized by XRD, N2 adsorption-desorption and UV-vis. The photocatalytic activity of the sample was evaluated by degrading methylene blue (MB) aqueous solution under the UV light source and was compared with that of the commercial titania (Degussa P25). The results showed that the produced SnO2can degrade MB solution quickly and has comparative photocatalytic performance with P25 for degrading MB. This facile method supplies an effective way to prepare SnO2photocatalyst.

scholarly journals Oxygen-Deficient WO3/TiO2/CC Nanorod Arrays for Visible-Light Photocatalytic Degradation of Methylene Blue

Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1349
Author(s):  
Liaochuan Jiang ◽  
Xingyuan Gao ◽  
Shaoling Chen ◽  
Jangam Ashok ◽  
Sibudjing Kawi
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Electrochemical Reduction ◽  
Separation Efficiency ◽  
Photogenerated Electron ◽  
Charge Transfer Resistance ◽  
High Photocatalytic Activity ◽  
Carbon Cloth ◽  
Transfer Resistance ◽  
Construction Of Self

At present, TiO2 is one of the most widely used photocatalytic materials. However, the narrow response range to light limits the photocatalytic performance. Herein, we reported a successful construction of self-doped R-WO3/R-TiO2/CC nanocomposites on flexible carbon cloth (CC) via electrochemical reduction to increase the oxygen vacancies (Ovs), resulting in an enhanced separation efficiency of photo-induced charge carriers. The photocurrent of R-WO3/R-TiO2/CC at −1.6 V (vs. SCE) was 2.6 times higher than that of WO3/TiO2/CC, which suggested that Ovs could improve the response to sunlight. Moreover, the photocatalytic activity of R-WO3/TiO2/CC was explored using methylene blue (MB). The degradation rate of MB could reach 68%, which was 1.3 times and 3.8 times higher than that of WO3/TiO2/CC and TiO2/CC, respectively. Furthermore, the solution resistance and charge transfer resistance of R-WO3/R-TiO2/CC were obviously decreased. Therefore, the electrochemical reduction of nanomaterials enabled a promoted separation of photogenerated electron–hole pairs, leading to high photocatalytic activity.

ZnO Photocatalysts Modified with Eu2O3 and Sm2O3

2020 ◽  
Vol 850 ◽  
pp. 35-40
Author(s):  
Pāvels Rodionovs ◽  
Jānis Grabis
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Hydrothermal Method ◽  
High Photocatalytic Activity ◽  
Solar Light ◽  
Effect Of Ph ◽  
Microwave Assisted ◽  
Bet Analysis

In this study ZnO photocatalysts with different loading of Eu2O3 and Sm2O3 were prepared vie microwave-assisted hydrothermal method. The prepared samples were investigated by using XRD, SEM and BET analysis. The photocatalytic activity was determined by degradation of methylene blue (MB) under Osram Vitalux illumination. Prepared ZnO photocatalysts shown high photocatalytic activity under solar light simulated radiation. After 30 minute of irradiation more than 95 % of initial MB solution was degraded. The effect of pH and photocatalyst dosage was investigated. The reusability of photocatalysts was also studied.

scholarly journals Solvent-Free Process for the Development of Photocatalytic Membranes

Molecules ◽  
2019 ◽  
Vol 24 (24) ◽  
pp. 4481 ◽  
Author(s):  
Rosa M. Huertas ◽  
Maria C. Fraga ◽  
João G. Crespo ◽  
Vanessa J. Pereira
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Sol Gel ◽  
Ceramic Membranes ◽  
High Photocatalytic Activity ◽  
Solvent Free ◽  
Narrow Pore Size Distribution ◽  
Free Process ◽  
Solvent Free Conditions ◽  
Bacteria And Fungi

This work described a new sustainable method for the fabrication of ceramic membranes with high photocatalytic activity, through a simple sol-gel route. The photocatalytic surfaces, prepared at low temperature and under solvent-free conditions, exhibited a narrow pore size distribution and homogeneity without cracks. These surfaces have shown a highly efficient and reproducible behavior for the degradation of methylene blue. Given their characterization results, the microfiltration photocatalytic membranes produced in this study using solvent-free conditions are expected to effectively retain microorganisms, such as bacteria and fungi that could then be inactivated by photocatalysis.

Improved Photocatalytic Activity of Copper Heterostructure Composites (Cu–Cu2O–CuO/AC) Prepared by Simple Carbothermal Reduction

2014 ◽  
Vol 67 (5) ◽  
pp. 749 ◽  
Author(s):  
Hongchao Ma ◽  
Yifeng Liu ◽  
Yinghuan Fu ◽  
Chunling Yu ◽  
Xiaoli Dong ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Photocatalytic Activity ◽  
Activated Carbon ◽  
Visible Light ◽  
Photoelectron Spectroscopy ◽  
Carbothermal Reduction ◽  
Treatment Time ◽  
Carbon Support ◽  
Treatment Temperature ◽  
X Ray

Cu–Cu2O–CuO/activated carbon heterostructure composites with visible-light activity have been successfully synthesized by a simple carbothermal reduction procedure using CuSO4 as a single precursor. The resultant samples were characterized by X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy measurements. The results showed that the Cu–Cu2O–CuO composites with size less than 10 nm dispersed well on the surface of activated carbon. Activated carbon played both a reducing agent and support role in the formation of Cu–Cu2O–CuO/activated carbon heterostructure composites. X-ray photoelectron spectroscopy analysis suggests that the outside of the nanoparticles is CuO and the inside of the nanoparticles is Cu metal and Cu2O. Moreover, the composition of Cu–Cu2O–CuO/activated carbon composites can be tailored by varying the Cu loading, heat-treatment temperature, and heat-treatment time. The photocatalytic activities of the catalysts were investigated by degrading reactive brilliant blue KN-R under visible-light irradiation. The Cu–Cu2O–CuO/activated carbon heterostructure composites showed excellent photocatalytic activity compared with other catalysts (pure CuO, Cu2O, Cu2O/activated carbon, CuO/activated carbon, and Cu2O–CuO/activated carbon), which is ascribed to synergistic action between the activated carbon support and photoactive copper species, and the presence of interfacial structures such as a Cu2O/CuO heterostructure, Cu/Cu2O (or CuO) Schottky barrier, and Cu2O/Cu/CuO ohmic heterojunction.

scholarly journals Synthesis of copper oxide nano-rice structures for enhancement of photocatalytic activity under natural sunlight

2019 ◽  
Vol 20 (5) ◽  
pp. 253-262
Author(s):  
Roonak Abdul Salam A.Alkareem
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Electron Microscope ◽  
Copper Oxide ◽  
High Photocatalytic Activity ◽  
X Ray Diffraction ◽  
Methylene Blue Degradation ◽  
X Ray ◽  
Uv Visible ◽  
Scanning Electron

In this work, copper oxide (CuO) nano-rice structure was prepared by hydrothermal method. The prepared samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), and UV-visible spectrophotometer. CuO nano-rice structure showed high photocatalytic activity towards degradation of methylene blue (MB). Hydrothermally growth of CuO provided uniformly distributed nano-rice structures with high degradation efficiency (90.41%) and rate constant (kt) 16.6 × 10-2 min-1 for methylene blue degradation.

A green method to prepare TiO2/MWCNT nanocomposites with high photocatalytic activity and insights into the effect of heat treatment on photocatalytic activity

RSC Advances ◽  
2015 ◽  
Vol 5 (18) ◽  
pp. 13430-13436 ◽  
Author(s):  
Qingping Zeng ◽  
Hua Li ◽  
Huanan Duan ◽  
Yiping Guo ◽  
Xuefa Liu ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Photocatalytic Activity ◽  
High Photocatalytic Activity ◽  
Uniform Loading ◽  
Green Method

We demonstrate a green method to prepare TiO2/MWCNT with uniform loading and high photocatalytic activity, and study the effect of heat treatment on the photocatalytic activity.

PHOTOCATALYTIC AND ANTIBACTERIAL ACTIVITY OF TITANIUM, FLUORINE AND SILVER CO-SUBSTITUTED HYDROXYAPATITE

2013 ◽  
Vol 22 ◽  
pp. 268-277 ◽  
Author(s):  
M. SANDHYARANI ◽  
N. RAMESHBABU ◽  
K. VENKATESWARLU ◽  
K. V. RAVISANKAR ◽  
M. ASHOK ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Heat Treatment ◽  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Crystal Size ◽  
Potential Candidate ◽  
Visible Light Photocatalytic Activity ◽  
Heat Treated Condition ◽  
Visible Light Photocatalytic

Synthetic hydroxyapatite (HA), an analogue of the mineral component of bone tissue has been widely used in medicine as bone replacing material. To impart specific properties, HA can be chemically modified by anionic and cationic substitutions during synthesis. Thus the present study was focused in synthesizing nanocrystalline Ti , Ag and F co-substituted HA by microwave synthesis. The prepared powders were characterized by XRD and FTIR for their crystal size, cystallinity and functional groups respectively. XRD spectra reveal that crystal size of prepared powders was in the range of 21–25 nm in as synthesized condition and 45–51 nm in 900 ˚C heat-treated condition. Complete decomposition of HA to tri calcium phosphate was observed for Ti substituted HA powder after heat-treatment. Addition of F improved the thermal stability of Ti substituted HA as indicated by predominant phase of HA after heat-treatment. The photocatalytic activity of co-substituted HA powders was examined by degradation of methylene blue (5 × 10−5 M concentration) under visible light irradiation and the results were compared with pure HA . The degradation efficiency of co-substituted HA with respect to methylene blue was twice as high as that of pure HA. Ti and Ag has improved the visible light photocatalytic activity of HA, further F co-substitution has not affected the photocatalytic activity of substituted HA. The antibacterial effect of prepared powders was observed against 1 × 105 cells/mL of Escherichia coli using spread plate method at 24 h incubation period. Ag co-substituted HA showed complete inhibition of growth of Escherichia coli. Thus, among Ti , Ti-F , Ti-F-Ag substituted HA powders, Ti-F-Ag co-substituted HA with excellent visible light photocatalytic activity and anti-bacterial property is expected to be a potential candidate for biomedical applications.

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