Photocatalytic Degradation of Methylene Blue under UV Light Irradiation on Prepared Carbonaceous <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-4.374pt" id="M1" height="16.4128pt" version="1.1" viewBox="-0.0657574 -12.0388 36.1679 16.4128" width="36.1679pt"><g transform="matrix(.018,0,0,-0.018,0,0)"><path id="g190-85" d="M592 498C586 556 582 629 581 675H560C545 656 537 650 510 650H115C87 650 74 652 60 675H40C38 620 33 555 28 495H57C69 539 77 568 89 585C102 607 122 616 205 616H267V123C267 44 259 34 168 28V0H454V28C360 34 352 44 352 123V616H422C498 616 514 608 531 584C542 568 552 543 562 495L592 498Z"/></g><g transform="matrix(.018,0,0,-0.018,10.747,0)"><path id="g190-106" d="M135 536C164 536 186 560 186 587C186 617 164 639 136 639C109 639 85 617 85 587C85 560 109 536 135 536ZM252 0V26C188 32 181 38 181 106V451C138 433 90 420 39 412V388C99 379 102 374 102 312V106C102 38 95 32 32 26V0H252Z"/></g><g transform="matrix(.018,0,0,-0.018,15.54,0)"><path id="g190-80" d="M381 665C170 665 44 498 44 318C44 125 188 -15 369 -15C552 -15 703 117 703 333C703 534 550 665 381 665ZM359 629C491 629 601 517 601 306C601 114 502 21 390 21C249 21 146 158 146 346S248 629 359 629Z"/></g><g transform="matrix(.013,0,0,-0.013,29.008,4.308)"><path id="g22-48" d="M440 180C404 113 397 110 338 110H183L298 220C398 316 438 379 438 456C438 568 354 635 254 635C192 635 138 610 101 572L36 479L69 452C103 500 144 541 204 541C270 541 306 494 306 425C306 350 267 276 197 193C148 136 89 81 36 30V0H440C451 42 463 106 480 167L440 180Z"/></g></svg>

Che Ramli, Zatil Amali; Asim, Nilofar; Isahak, Wan N. R. W.; Emdadi, Zeynab; Ahmad-Ludin, Norasikin; Yarmo, M. Ambar; Sopian, K.

doi:https://doi.org/10.1155/2014/415136

The Scientific World Journal

On this page

Abstract Introduction Experimental Results Conclusion Acknowledgments References Copyright Related Articles

Research Article | Open Access

Volume 2014 | Article ID 415136 | https://doi.org/10.1155/2014/415136

Photocatalytic Degradation of Methylene Blue under UV Light Irradiation on Prepared Carbonaceous

Zatil Amali Che Ramli,¹Nilofar Asim,¹Wan N. R. W. Isahak,²Zeynab Emdadi,¹Norasikin Ahmad-Ludin,¹M. Ambar Yarmo,²and K. Sopian¹

Academic Editor: Liqiang Jing

Received06 Feb 2014

Accepted07 May 2014

Published11 Jun 2014

Abstract

This study involves the investigation of altering the photocatalytic activity of TiO₂ using composite materials. Three different forms of modified TiO₂, namely, TiO₂/activated carbon (AC), TiO₂/carbon (C), and TiO₂/PANi, were compared. The TiO₂/carbon composite was obtained by pyrolysis of TiO₂/PANi prepared by in situ polymerization method, while the TiO₂/activated carbon (TiO₂/AC) was obtained after treating TiO₂/carbon with 1.0 M KOH solution, followed by calcination at a temperature of 450°C. X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR), thermogravimetric analysis (TG-DTA), Brunauer-Emmet-Teller (BET), and UV-Vis spectroscopy were used to characterize and evaluate the prepared samples. The specific surface area was determined to be in the following order: TiO₂/AC > TiO₂/C > TiO₂/PANi > TiO₂ (179 > 134 > 54 > 9 m² g⁻¹). The evaluation of photocatalytic performance for the degradation of methylene blue under UV light irradiation was also of the same order, with 98 > 84.7 > 69% conversion rate, which is likely to be attributed to the porosity and synergistic effect in the prepared samples.

1. Introduction

Currently, the rapid industrialization in developing countries has begun to introduce harmful organic pollutants into the water supply. These effluents are also sourced from the textile industry that consumes a large quantity of water in the process of dyeing and washing of fabrics and the release of huge quantities of dyes [1]. Therefore, the development of inexpensive and green methods to treat and purify contaminated water has been the focal subject in technological developments. Among many strategies, photocatalysis is regarded as the most viable one, especially for treatment of contaminants, due to its usage of sunlight to decompose organic pollutants [2–4]. Titanium dioxide or titania (TiO₂) acts as an agent in this process [5, 6]. However, TiO₂ is not without its drawback in the context of photocatalysis, such as its high band gap energy 3.2 eV for anatase [7], the limitation of photo response only under UV light region, and its high rate of electron and hole recombination. Attempts to address these problems involve doping, nonmetallic elements doping, surface modification, forming composites with narrow semiconductors, using semiconductor polymer as support, and coating with carbon layers to improve and enhance the photocatalytic activity of titanium dioxide.

Current literature shows that activated carbon is gaining attention as it is capable of modifying TiO₂ photocatalyst. The work in [8–12] showed that this enhancement is caused by porous structure of activated carbon, which provides a large surface area for photoactive TiO₂ particle.

The work in [8, 13–15] found the synergistic effect of the mixture of TiO₂ with activated carbon (AC). The improvement of TiO₂/AC composite was explained by the high adsorption of the impurities on the surface of activated carbon and their transfer to the TiO₂ surface. In this study, carbonaceous TiO₂, namely, TiO₂/activated carbon (AC), TiO₂/carbon (C), and TiO₂/PANi were prepared and evaluated for photocatalytic performance for degradation of methylene blue under UV light irradiation. The carbon and activated carbon/TiO₂ were synthesized using polyaniline (PANi) as its carbon source.

2. Experimental and Characterizations

2.1. Preparation of TiO₂/Polyaniline and TiO₂/Carbon

TiO₂/polyaniline (TiO₂/PANi) was synthesized using TiO₂ (Sigma Aldrich, 99.9% purity) and aniline hydrochloride (Sigma Aldrich, 99.95%). In order to synthesize TiO₂/PANi, 0.2 mol cm⁻³ aniline hydrochloride solution was prepared by adding 259 mg aniline hydrochloride to 5 mL deionized water and was vigorously stirred for 10 minutes at a temperature of 60°C. TiO₂ powder, with various percentages (5%, 10% and 15%), is added to aniline hydrochloride solution being prepared previously. 0.25 mol cm⁻³ ammonium peroxydisulphate solution was prepared by adding 571 mg ammonium peroxydisulphate (Sigma Aldrich, 98% reagent grade) in 5 mL deionized water. While the mixture above was being stirred, the prepared ammonium peroxydisulphate solution was added to the mixture and was stirred for an additional 10 minutes. The polymerization was completed in about 10 minutes. The solution was then left to dry at room temperature for 48 hours. The precipitate powder was then centrifuged and washed with absolute ethanol, followed by distilled water in order to remove unreacted aniline monomer and its corresponding by-products. The product (TiO₂/PANi) was dried at 65°C for 24 h. The composite that was the result of the process was labeled as TiO₂/PANi. The product was then pyrolyzed at a temperature of 450°C for 1 hour in nitrogen flow at a heating rate of 10°C min⁻¹ to produce titania/carbon (TiO₂/C).

2.2. Chemical Activation of TiO₂/Carbon

In order to produce porous carbon or the so-called activated carbon, the TiO₂/C was treated with 1.0 M KOH solution. About 0.3 g TiO₂/C was mixed with 2.5 mL 1.0 M KOH solution. The mixture was then heated at a temperature of 450°C under nitrogen gas flow for 1 hour. Then the treated sample was washed with deionized water until it was neutral and dried overnight at a temperature of 100°C and was labeled TiO₂/AC. Since the early photocatalytic performance tests demonstrated better result for the TiO₂/AC prepared from 15% TiO₂/PANi, the characterization was done for 15% TiO₂/PANi and the resulting TiO₂/C and TiO₂/AC (hereafter denoted as TiO₂/PANi, TiO₂/C, and TiO₂/AC, resp.).

2.3. Characterizations

The functionality groups of the samples were determined using FTIR spectra. The morphology and structure of the samples were determined by field emission scanning electron microscope (FESEM, ZEISS Supra VP55) and transmission electron microscope (JEOL JEM-2100). The specific surface area, pore size, pore volume, and pore diameter of the samples were determined by Brunauer-Emmet-Teller (BET) method [16] using a nitrogen adsorption instrument (Micrometics ASAP 2010). The samples were degassed at 100°C for 24 hours prior to the analysis. Pore size distribution was calculated from the adsorption desorption of the isotherms using the Barret-Joyner-Halenda (BJH) model [17], while the crystallinity of the samples was analyzed using Brucker DB-advance X-ray diffractometer (XRD). The analyses were done under the setting of Cu k radiation at 2 theta, ranging from 10° to 80° for a 1-gram sample. The particle size of the sample was calculated by applying Scherrer’s equation. Thermal gravimetric analysis (TGA) with a simultaneous TGA-DTG system (model: Mettler Toledo) has been used for investigation of thermal stability of samples. To reduce the influence of the sample quantity on the analyses, mg of each sample was used in each analysis with a constant nitrogen (N₂) flow 50.0 mL min⁻¹ maintained throughout the entire process. To minimize possible differences in the moisture content between samples, all TGA samples were equilibrated at 50°C for 5 min before being heated to 700°C at a ramping rate of 5°C min⁻¹.

For investigation of prepared samples recyclability, the used catalyst was separated from reaction mixture by filtration. After that, it is washed with distilled water several times and dried in oven to be reused for next reaction cycle. Then they were used for subsequent cycles under similar reaction conditions as carried out by fresh catalyst.

2.4. Photocatalytic Experimental

The photocatalytic activities of the samples were evaluated via the photocatalytic oxidation of methylene blue (MB) under UV light irradiation. A 15 watt UV bench lamp was used as a light source. Since the photocatalytic test took into account different MB concentrations (0.05, 0.1, and 0.15 mM) and different irradiation times, it showed better results for 0.05 mM and 90 minutes, respectively, and was selected as the test condition (see Section 3.2).

Prior to illumination, 20 mg photocatalyst was added to the MB solution (20 mL, 0.05 mM). The solution was stirred in the dark for 30 minutes in order to reach MB absorption-desorption equilibrium, which will then allow for the commencement of the photocatalytic reaction. The photocatalyst will then be exposed to the UV lamp for 90 minutes in room temperature. The results after this time period will be evaluated after 90 minutes.

The degradation efficiency of MB was analyzed using UV-Vis spectrometer. Peaks were observed to be present between 600 and 700 nm and were assigned as the absorption of the π-system [18], which was indicative of the degradation of MB. According to Beer-Lambert Law, MB’s concentration is directly proportional to its absorbance. This makes it possible to determine the oxidation efficiency of MB using the following equation: where is the initial concentration of MB solution and is concentration of MB during irradiation.

3. Results and Discussions

The existence of polyaniline on the TiO₂ surface particle was verified by IR spectra. The characteristic bands of TiO₂, polyaniline (made in the same way for comparison purpose only), TiO₂/PANi, and TiO₂/AC are shown in Figures 1(a), 1(b), 1(c), and 1(d), respectively. The FTIR spectrum of polyaniline was clearly observed in TiO₂/PANi sample. The spectra display the two bands at 1490 and 1585 cm⁻¹, which were assigned to benzenoid and quinoide rings. The band at 1300 cm⁻¹ is related to C–N stretching of a secondary aromatic amine, while the band at 1140 cm⁻¹ is attributed to the vibration mode of the polymer. These bands reveal the existence of PANi in the synthesized TiO₂/PANi sample. In TiO₂ and TiO₂/AC spectra, peaks around 3400 cm⁻¹ were assigned to –OH stretching, while those at 1600 cm⁻¹ were assigned to –OH vibration. These peaks can be attributed to the adsorbed water from the environment.

The morphologies and size of the prepared nanoparticles were studied by variable pressure scanning electron microscope (VPSEM) and transmission electron microscopy (TEM) (Figures 2 and 3).

(a)

(b)

(c)

(d)

(a)

(b)

(c)

(d)

From the TEM image of Figure 3(a), it was shown that bare TiO₂ particles are uniform in shape, with sizes ranging from 25 to 30 nm. Figure 3(b) shows TiO₂/PANi composite, where the sizes range from 30 to 40 nm. Both TEM and FESEM photographs show that there is no significant difference of particle size of the samples TiO₂/C and TiO₂/AC (before and after chemical activation of KOH solution) (40–80 nm). This agrees with previous studies, which reported that the sintering effect did not occur for TiO₂/carbon after being heated at temperatures below 700°C [19].

The XRD patterns of the prepared samples were shown in Figure 4. The main diffraction peaks were at 25.3°, 37.8°, 48°, 54°, and 62.6°, assigned to the diffraction planes of (1 0 1), (0 0 4), (2 0 0), (1 0 5), and (2 0 4) for anatase (JCPDS number 021-1272), respectively. Other crystal phases corresponding to the peaks at 27.4 and 36.1° were assigned to the diffraction peaks of (1 1 0) and (1 0 1) of rutile (JCPDS number 021-1276), respectively. The XRD patterns revealed the diffraction peaks of a mixture of anatase and rutile in the prepared samples, which is favorable for photocatalytic reactions [20–23]. XRD also showed that the preparation of TiO₂ composites did not affect the crystal structure of TiO₂, but the peaks intensity became lower and its shape got wider, especially in the case of TiO₂/PANi. This can be attributed to certain crystalline structure in PANi overlapping TiO₂ peaks, but this effect is less pronounced in TiO₂/C and TiO₂/AC. The anatase content () was determined from the integrated intensity of the anatase diffraction line (1 0 1), , and that of the rutile diffraction line (1 1 0), , using the following equation [24] and the results are listed in Table 1: The values showed that the rutile phase is dominant in all of the prepared samples. Besides that, the crystallite size of the samples was calculated by applying the Scherrer equation on the plane (101) diffraction peak of anatase and (110) diffraction peak of rutile, as listed in Table 1. The BET surface area, pore size, micropore area, and volumes are listed in Table 1 as well. The results showed that the specific surface area adhered to the following order: TiO₂/AC > TiO₂/C > TiO₂/PANi >TiO₂ (179 >134 > 54 > 9 m²g⁻¹). This suggests that the characteristics of the composited catalyst were enhanced, as it provided more active sites for photocatalytic reactions to take place.

The thermal stability of the prepared TiO₂/PANi and TiO₂/AC was investigated and the TG-DTA analysis results are shown in Figure 5. The first weight loss took place in the range of temperature 50–120°C for TiO₂/PANi, which is 6.5% decrease from the original weight. The weight loss is due to the loss of moisture or water content, the evaporation of solvents such as ethanol and small molecules from the polymer matrix [25]. The second loss was determined at temperatures between 310 and 700°C. During this step, the weight loss was attributed to the degradation of polyaniline main chain (about 54%) [26–28]. At a temperature of about 700°C, the PANi molecule was completely decomposed to carbon. The result showed that TiO₂/AC has significantly improved thermal stabilities compared to TiO₂/PANi.

3.1. Evaluation of Photocatalytic Performance

The degradation of methylene blue (MB) was used in this work in order to evaluate the photocatalytic activity of the prepared samples. The effect of different loading percentages of TiO₂ in activated carbon on photocatalytic activity has been investigated as well (Figure 6). The results showed that increasing the content of TiO₂ improves photocatalytic performances. From the tests, it was determined that the 15% TiO₂ loading was to be further tested.

It is known that the concentration of methylene blue influences the photocatalytic performance of the samples [29]. Therefore, in this study, the photocatalytic activity of TiO₂/PANi and TiO₂/AC (0.05 mM) using different concentrations of MB within 90 minutes irradiation time was studied. It can be seen that TiO₂/activated carbon demonstrated superior photocatalytic activity for all different concentrations of MB (Figure 7).

The photocatalytic activity was also evaluated using irradiation time acting as its parameter (Figure 8). The result show rapid increase in MB degradation from 0 to 30 minutes which becomes slower after 30 minutes for both samples. The much higher MB degradation rate for TiO₂/AC proves its better performance compared to TiO₂/PANi. TiO₂/AC showed almost complete degradation of MB after 90 minutes of irradiation.

Figure 9 presents the result of the degradation of MB for bare TiO₂, TiO₂/PANi, TiO₂/C, and TiO₂/AC. The experiment was carried out in 90-minute irradiation, and the concentration of methylene blue was 0.05 mM for all samples. The degradation of MB without catalyst was used as a reference.

The results can be explained using texture properties of the prepared samples, as shown in Table 1. The specific surface area, micropore area, and volume adhered to the trend TiO₂/AC > TiO₂/C > TiO₂/PANi >TiO₂, which is similar to photocatalytic performance. This is attributed to the higher porosity of the activated carbon compered to others, which provide high adsorption capacity and more active sites for the reacting species during chemical reaction, which agrees with previous studies [8, 9, 19, 30–32]. It was noted that the surface area of TiO₂/AC is larger compared to the ones reported in the literature, which used polystyrene (PS) as a carbon source [33]. It also shows that PANi is a better source for the preparation of highly porous activated carbon.

On top of the synergistic effect for the mixture of TiO₂ with activated carbon and highly porous structures, the high photocatalytic performance could be the result of the mixture of anatase and rutile phase of TiO₂ in this work (Table 1). This can be explained by the synergic effect between anatase and rutile in TiO₂ particles that are approximately close to each other, thus enhancing the activity [34]. This finding is in agreement with other studies reporting that the photocatalytic activity was enhanced when anatase and rutile were mixed [34, 35].

3.2. Recyclability of TiO₂/AC

Recyclability test was carried out for TiO₂/AC to up to five cycles. The results are depicted in Figure 10, demonstrating good recyclability for the prepared composite.

4. Conclusion

Regarding the possibility of photocatalytic improvement using a composite of TiO₂, a different form of modified TiO₂, namely, TiO₂/activated carbon (AC), TiO₂/Carbon (C), and TiO₂/PANi, were synthesized and characterized, and their catalytic performance have been studied. The effect of TiO₂ loading, irradiation time, and MB concentration has been studied. TiO₂/AC showed the highest porosity and photocatalytic performance compared to other composites. On top of considering the synergistic effect for the mixture of TiO₂ with activated carbon and its high porosity, this high performance can also be attributed to the anatase and rutile mixture. Meanwhile, PANi demonstrated better AC source compared to previous works, and the recyclability test demonstrated excellent performance for the synthesized composite.

Conflict of Interests

The authors declare that there is no conflict of interests regarding the publication of this paper.

Acknowledgments

The authors would like to acknowledge the financial support of the work by the Universiti Kebangsaan Malaysia for funding this project under the research Grants of Dana Impak Perdana (DLP-2013-015 and FRGS/1/2012/TK07/UKM/3/4) from Ministry of Higher Education (MOHE), Malaysia, and Centre of Research and Innovation Management (CRIM), UKM.

References

S. Hussain, Z. Maqbool, S. Ali et al., “Biodecolorization of reactive black-5 by a metal and salt tolerant bacterial strain Pseudomonas sp. RA20 isolated from Paharang drain effluents in Pakistan,” Ecotoxicology and Environmental Safety, vol. 98, pp. 331–338, 2013.
View at: Google Scholar
J. Zhao, C. Chen, and W. Ma, “Photocatalytic degradation of organic pollutants under visible light irradiation,” Topics in Catalysis, vol. 35, pp. 269–278, 2005.
View at: Google Scholar
D. Bahnemann, “Photocatalytic water treatment: solar energy applications,” Solar Energy, vol. 77, no. 5, pp. 445–459, 2004.
View at: Publisher Site | Google Scholar
U. I. Gaya and A. H. Abdullah, “Heterogeneous photocatalytic degradation of organic contaminants over titanium dioxide: a review of fundamentals, progress and problems,” Journal of Photochemistry and Photobiology C: Photochemistry Reviews, vol. 9, no. 1, pp. 1–12, 2008.
View at: Publisher Site | Google Scholar
M. R. Hoffmann, S. T. Martin, W. Choi, and D. W. Bahnemann, “Environmental applications of semiconductor photocatalysis,” Chemical Reviews, vol. 95, no. 1, pp. 69–96, 1995.
View at: Google Scholar
O. Carp, C. L. Huisman, and A. Reller, “Photoinduced reactivity of titanium dioxide,” Progress in Solid State Chemistry, vol. 32, no. 1-2, pp. 33–177, 2004.
View at: Publisher Site | Google Scholar
T. Tachikawa, M. Fujitsuka, and T. Majima, “Mechanistic insight into the TiO₂ photocatalytic reactions: design of new photocatalysts,” Journal of Physical Chemistry C, vol. 111, no. 14, pp. 5259–5275, 2007.
View at: Publisher Site | Google Scholar
S. X. Liu, X. Y. Chen, and X. Chen, “A TiO₂/AC composite photocatalyst with high activity and easy separation prepared by a hydrothermal method,” Journal of Hazardous Materials, vol. 143, no. 1-2, pp. 257–263, 2007.
View at: Publisher Site | Google Scholar
L. F. Velasco, J. B. Parra, and C. O. Ania, “Role of activated carbon features on the photocatalytic degradation of phenol,” Applied Surface Science, vol. 256, no. 17, pp. 5254–5258, 2010.
View at: Publisher Site | Google Scholar
W. N. R. W. Isahak, M. W. M. Hisham, and M. A. Yarmo, “Highly porous carbon materials from biomass by chemical and carbonization method: a comparison study,” Journal of Chemistry, vol. 2013, Article ID 620346, 6 pages, 2013.
View at: Publisher Site | Google Scholar
T. Torimoto, Y. Okawa, N. Takeda, and H. Yoneyama, “Effect of activated carbon content in TiO₂-loaded activated carbon on photodegradation behaviors of dichloromethane,” Journal of Photochemistry and Photobiology A: Chemistry, vol. 103, no. 1-2, pp. 153–157, 1997.
View at: Google Scholar
B. Tryba, “Increase of the photocatalytic activity of TiO₂ by carbon and iron modifications,” International Journal of Photoenergy, vol. 2008, Article ID 721824, 15 pages, 2008.
View at: Publisher Site | Google Scholar
J. Matos, J. Laine, and J. Herrmann, “Association of activated carbons of different origins with titania in the photocatalytic purification of water,” Carbon, vol. 37, no. 11, pp. 1870–1872, 1999.
View at: Publisher Site | Google Scholar
J. Araña, J. M. Doña-Rodríguez, E. Tello Rendón et al., “TiO₂ activation by using activated carbon as a support: part I. Surface characterisation and decantability study,” Applied Catalysis B: Environmental, vol. 44, pp. 161–172, 2003.
View at: Google Scholar
J. Araña, J. M. Doña-Rodríguez, E. Tello Rendón et al., “TiO₂ activation by using activated carbon as a support: part II. Photoreactivity and FTIR study,” Applied Catalysis B: Environmental, vol. 44, pp. 153–160, 2003.
View at: Google Scholar
S. Brunauer, P. H. Emmett, and E. Teller, “Adsorption of gases in multimolecular layers,” Journal of the American Chemical Society, vol. 60, no. 2, pp. 309–319, 1938.
View at: Google Scholar
E. P. Barrett, L. G. Joyner, and P. P. Halenda, “The determination of pore volume and area distributions in porous substances. I. Computations from nitrogen isotherms,” Journal of the American Chemical Society, vol. 73, no. 1, pp. 373–380, 1951.
View at: Google Scholar
G. Liu, T. Wu, J. Zhao, H. Hidaka, and N. Serpone, “Photoassisted degradation of dye pollutants. 8. Irreversible degradation of alizarin red under visible light radiation in air-equilibrated aqueous TiO₂ dispersions,” Environmental Science and Technology, vol. 33, no. 12, pp. 2081–2087, 1999.
View at: Publisher Site | Google Scholar
B. Tryba, A. W. Morawski, and M. Inagaki, “Application of TiO₂-mounted activated carbon to the removal of phenol from water,” Applied Catalysis B: Environmental, vol. 41, no. 4, pp. 427–433, 2003.
View at: Publisher Site | Google Scholar
J. Ovenstone, “Preparation of novel titania photocatalysts with high activity,” Journal of Materials Science, vol. 36, no. 6, pp. 1325–1329, 2001.
View at: Publisher Site | Google Scholar
J. Moon, H. Takagi, Y. Fujishiro, and M. Awano, “Preparation and characterization of the Sb-doped TiO₂ photocatalysts,” Journal of Materials Science, vol. 36, no. 4, pp. 949–955, 2001.
View at: Publisher Site | Google Scholar
S. S. Arbuj, R. R. Hawaldar, U. P. Mulik, B. N. Wani, D. P. Amalnerkar, and S. B. Waghmode, “Preparation, characterization and photocatalytic activity of TiO₂ towards methylene blue degradation,” Materials Science and Engineering B: Solid-State Materials for Advanced Technology, vol. 168, no. 1, pp. 90–94, 2010.
View at: Publisher Site | Google Scholar
M. Toyoda, Y. Nanbu, Y. Nakazawa, M. Hirano, and M. Inagaki, “Effect of crystallinity of anatase on photoactivity for methyleneblue decomposition in water,” Applied Catalysis B: Environmental, vol. 49, no. 4, pp. 227–232, 2004.
View at: Publisher Site | Google Scholar
R. A. Spurr, “Quantitative analysis of anatase-rutile mixtures with an X-ray diffractometer,” Analytical Chemistry, vol. 29, no. 5, pp. 760–762, 1957.
View at: Google Scholar
A. H. Elsayed, M. S. Mohy Eldin, A. M. Elsyed, A. H. Abo Elazm, E. M. Younes, and H. A. Motaweh, “Synthesis and properties of polyaniline/ferrites nanocomposites,” International Journal of Electrochemical Science, vol. 6, no. 1, pp. 206–221, 2011.
View at: Google Scholar
J. Deng, X. Ding, W. Zhang et al., “Magnetic and conducting Fe₃O₄-cross-linked polyaniline nanoparticles with core-shell structure,” Polymer, vol. 43, no. 8, pp. 2179–2184, 2002.
View at: Google Scholar
N. Asim, S. Radiman, and M. A. B. Yarmo, “Preparation and characterization of core-shell polyaniline/V₂O₅ nanocomposite via microemulsion method,” Materials Letters, vol. 62, no. 6-7, pp. 1044–1047, 2008.
View at: Publisher Site | Google Scholar
S. Lee, Y. Chen, C. Ho, C. Chang, and Y. Hong, “A study on synthesis and characterization of the core-shell materials of Mn_1-xZn_xFe₂O₄-polyaniline,” Materials Science and Engineering B: Solid-State Materials for Advanced Technology, vol. 143, no. 1–3, pp. 1–6, 2007.
View at: Publisher Site | Google Scholar
R. M. Mohamed, I. A. Mkhalid, E. S. Baeissa, and M. A. Al-Rayyani, “Photocatalytic degradation of methylene blue by Fe/ZnO/SiO₂ nanoparticles under visiblelight,” Journal of Nanotechnology, vol. 2012, Article ID 329082, 5 pages, 2012.
View at: Publisher Site | Google Scholar
Y. Li, S. Zhang, Q. Yu, and W. Yin, “The effects of activated carbon supports on the structure and properties of TiO₂ nanoparticles prepared by a sol-gel method,” Applied Surface Science, vol. 253, no. 23, pp. 9254–9258, 2007.
View at: Publisher Site | Google Scholar
X. Wang, Z. Hu, Y. Chen, G. Zhao, Y. Liu, and Z. Wen, “A novel approach towards high-performance composite photocatalyst of TiO₂ deposited on activated carbon,” Applied Surface Science, vol. 255, no. 7, pp. 3953–3958, 2009.
View at: Publisher Site | Google Scholar
X. Zhang, M. Zhou, and L. Lei, “Preparation of photocatalytic TiO₂ coatings of nanosized particles on activated carbon by AP-MOCVD,” Carbon, vol. 43, no. 8, pp. 1700–1708, 2005.
View at: Publisher Site | Google Scholar
S. Lubis, L. Yuliati, S. L. Lee, I. Sumpono, and H. Nur, “Improvement of catalytic activity in styrene oxidation of carbon-coated titania by formation of porous carbon layer,” Chemical Engineering Journal, vol. 209, pp. 486–493, 2012.
View at: Publisher Site | Google Scholar
T. Ohno, K. Tokieda, S. Higashida, and M. Matsumura, “Synergism between rutile and anatase TiO₂ particles in photocatalytic oxidation of naphthalene,” Applied Catalysis A: General, vol. 244, no. 2, pp. 383–391, 2003.
View at: Publisher Site | Google Scholar
C. Wu, Y. Yue, X. Deng, W. Hua, and Z. Gao, “Investigation on the synergetic effect between anatase and rutile nanoparticles in gas-phase photocatalytic oxidations,” Catalysis Today, vol. 93–95, pp. 863–869, 2004.
View at: Publisher Site | Google Scholar

Copyright

Copyright © 2014 Zatil Amali Che Ramli et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

PDF Download Citation

Download other formats

Order printed copies

Views

15349

Downloads

3293

Citations