Role of RGO support and irradiation source on the photocatalytic activity of CdS–ZnO semiconductor nanostructures

• Suneel Kumar,
• Rahul Sharma,
• Vipul Sharma,
• Gurunarayanan Harith,
• Vaidyanathan Sivakumar and
• Venkata Krishnan

Beilstein J. Nanotechnol. 2016, 7, 1684–1697, doi:10.3762/bjnano.7.161

• nanostructures. Keywords: catalytic properties; chemical synthesis; nanostructures; semiconductors; transmission electron microscopy (TEM); Introduction In the past decade, there has been an increased interest in the photocatalytic degradation of various kinds of organic pollutants in water and soil [1]. Many

• spectra of (a) GO, (b) ZnO, (c) CdS, (d) CdS–ZnO and (e) CdS–ZnO–RGO nanocomposite. UV–vis absorption spectra of GO, ZnO NR, CdS NP, CdS–ZnO and CdS–ZnO–RGO nanocomposite. Time-dependent UV–vis spectra of photocatalytic degradation of MO: (a) visible light irradiation from a solar simulator using CdS–ZnO

High performance Ce-doped ZnO nanorods for sunlight-driven photocatalysis

• Bilel Chouchene,
• Tahar Ben Chaabane,
• Lavinia Balan,
• Emilien Girot,
• Kevin Mozet,
• Ghouti Medjahdi and
• Raphaël Schneider

Beilstein J. Nanotechnol. 2016, 7, 1338–1349, doi:10.3762/bjnano.7.125

• ability of the Ce dopant to reduce charge recombinations is promising for the efficient photodegradation of pollutants. Photocatalytic degradation of Orange II We first investigated the photocatalytic activities of Ce-doped ZnO in comparison to ZnO rods in the photodegradation of Orange II used at a 10 mg

• min at pH 10 and 12, respectively). The high photocatalytic activity of the Ce-doped ZnO rods at basic pH may be attributed to the increased concentration of hydroxy anions that facilitate the photogeneration of hydroxy •OH radicals (−OH + h+ → •OH), thus enhancing the photocatalytic degradation

• successive runs, which indicates the good stability of ZnO:Ce rods. Only after seven cycles, C/C0 decreased to ca. 0.65. Photocatalytic degradation mechanism Scavenging experiments of the active species (•OH and O2•− radicals, e− and h+) were conducted to establish the mechanism of the photocatalytic

Effect of SiN_x diffusion barrier thickness on the structural properties and photocatalytic activity of TiO₂ films obtained by sol–gel dip coating and reactive magnetron sputtering

• Mohamed Nawfal Ghazzal,
• Eric Aubry,
• Nouari Chaoui and
• Didier Robert

Beilstein J. Nanotechnol. 2015, 6, 2039–2045, doi:10.3762/bjnano.6.207

• . An increased SiNx diffusion barrier thickness resulted in a decrease in the crystallite size of the TiO2 film when produced by the sol–gel method, and consequently, the photocatalytic degradation of the OII dye was improved. However, when the reactive sputtering method was used, the thickness of the

Effects of swift heavy ion irradiation on structural, optical and photocatalytic properties of ZnO–CuO nanocomposites prepared by carbothermal evaporation method

• Sini Kuriakose,
• D. K. Avasthi and
• Satyabrata Mohapatra

Beilstein J. Nanotechnol. 2015, 6, 928–937, doi:10.3762/bjnano.6.96

• photocatalytic degradation kinetics was observed by monitoring the characteristic peak of MB at 664 nm and MO at 464 nm as a function of sun light exposure time. It can be clearly seen that the photocatalytic efficiency is highest for the sample irradiated at a fluence of 1 × 1014 ions/cm2 as compared to the

• pristine samples and the samples irradiated with lower fluences. The schematic diagram showing the mechanism underlying the photocatalytic degradation of dye through ZnO–CuO nanocomposites is depicted in Figure 8. The mechanism of photocatalysis can be understood as follows. When sun light is incident on

• formation of hydroxyl radicals (•OH) and superoxide radicals (•O2−) during visible-light-induced photocatalytic degradation of acid orange and 4-nitrophenol. The formation of hydroxyl radicals (•OH) was detected by photoluminescence studies using terephthalic acid as a probe molecule, while 1,4-benzoquinone

Tm-doped TiO₂ and Tm₂Ti₂O₇ pyrochlore nanoparticles: enhancing the photocatalytic activity of rutile with a pyrochlore phase

• Desiré M. De los Santos,
• Javier Navas,
• Teresa Aguilar,
• Antonio Sánchez-Coronilla,
• Concha Fernández-Lorenzo,
• Rodrigo Alcántara,
• Jose Carlos Piñero,
• Ginesa Blanco and
• Joaquín Martín-Calleja

Beilstein J. Nanotechnol. 2015, 6, 605–616, doi:10.3762/bjnano.6.62

• obtained (Figure 8b), the photocatalytic degradation of MB, using our samples synthesized as a catalyst, is a pseudo-first-order reaction and its kinetics can be described by ln(c0/c) = −kKt = kappt, where c0 is the initial concentration of the MB, c is the concentration of the MB with irradiation time t

Palladium nanoparticles anchored to anatase TiO₂ for enhanced surface plasmon resonance-stimulated, visible-light-driven photocatalytic activity

• Kah Hon Leong,
• Hong Ye Chu,
• Shaliza Ibrahim and
• Pichiah Saravanan

Beilstein J. Nanotechnol. 2015, 6, 428–437, doi:10.3762/bjnano.6.43

• degradation of AMX are of pseudo-first-order (Figure 12). The obtained kinetics parameters are tabulated in Table S2 (Supporting Information File 1). Finally, the degree of mineralization of AMX during the photocatalytic degradation was also presented through a total organic carbon (TOC) analysis and depicted

• % Pd/TiO2, c) 3.0 wt % Pd/TiO2 and d) 1.0 wt % Pd/TiO2. Photocatalytic degradation rates of AMX under visible light irradiation. Schematic diagram of electron transfer and degradation mechanism of AMX. Recycled photocatalytic degradation rates of AMX (0.5 wt % Pd/TiO2). The kinetics of AMX degradation

• the as prepared 0.5 wt % Pd/TiO2 photocatalyst maintains a high level of degradation efficiency after three times of recycling. An efficiency of 92.3% was achieved after the 3rd run, which indicates an excellent photostability of the synthesized photocatalyst. The kinetics of the photocatalytic

Nanomanipulation and environmental nanotechnology

• Enrico Gnecco,
• Andre Schirmeisen,
• Carlos M. Pina and
• Udo Becker

Beilstein J. Nanotechnol. 2014, 5, 2079–2080, doi:10.3762/bjnano.5.216

• processes. For example, the photocatalytic degradation of pollutants can be interpreted using density functional theory. On a different scale, AFM measurements in liquid environments can be supported by advanced contact mechanics models including the squeeze-out of wetting fluids. Adhesion of fluorite

Characterization and photocatalytic study of tantalum oxide nanoparticles prepared by the hydrolysis of tantalum oxo-ethoxide Ta₈(μ₃-O)₂(μ-O)₈(μ-OEt)₆(OEt)₁₄

• Subia Ambreen,
• N D Pandey,
• Peter Mayer and
• Ashutosh Pandey

Beilstein J. Nanotechnol. 2014, 5, 1082–1090, doi:10.3762/bjnano.5.121

• increasing the amount of Ta2O5 from 0.2 mg/mL to 0.8 mg/mL, the photocatalytic degradation rate was enhanced due to increase in the active sites accessible for the reaction on the surface of the catalyst. However, when the amount of catalyst was increased further, the rate of dye degradation was found to be

• ground state molecules and thus reduce the degradation [31]. Effect of dye concentration on the rate of degradation of rhodamine B To study the effect of initial dye concentration on the photocatalytic degradation different amounts of rhodamine B were taken while keeping other factors constant. It was

• rhodamine B. Effect of dye concentration on photocatalytic degradation. Effect of dye concentration on photocatalytic degradation. Effect of the pH value on the rate of degradation of rhodamine B. Effect of the calcination temperature on the rate of degradation of rhodamine B. Selected bond lengths

DFT study of binding and electron transfer from colorless aromatic pollutants to a TiO₂ nanocluster: Application to photocatalytic degradation under visible light irradiation

• Corneliu I. Oprea,
• Petre Panait and
• Mihai A. Gîrţu

Beilstein J. Nanotechnol. 2014, 5, 1016–1030, doi:10.3762/bjnano.5.115

• order to explain experimental results regarding the photocatalytic degradation of these pollutants under visible light irradiation. Based on our modeling, we are able to clarify why transparent pollutants can degrade under visible light in the presence of a catalyst that absorbs only in the UV, to

• ; density functional theory; photocatalytic degradation; titanium dioxide; visible light irradiation; Introduction Titania, TiO2, has been widely used as photocatalyst for environmental applications [1][2][3][4][5][6], particularly for waste water purification. Due to its large band gap TiO2 absorbs only

• UV radiation, a fact that limits the efficiency and keeps the costs of the photocatalytic degradation of environmental pollutants high. To be used under visible light irradiation, in the range of wavelengths where the solar spectrum has its maximum, the electronic band structure of the photocatalyst

Nanostructure sensitization of transition metal oxides for visible-light photocatalysis

• Hongjun Chen and
• Lianzhou Wang

Beilstein J. Nanotechnol. 2014, 5, 696–710, doi:10.3762/bjnano.5.82

• composite photocatalysts in the case of the photocatalytic degradation of phenol under visible light irradiation [95] (Figure 7b). In this photo-excitation process, carbon nanotubes are firstly excited by visible light and transfer electrons to the CB of a transition metal oxide for the reduction reaction

• ) and then emit shorter wavelength light (300 to 530 nm) for the excitation of m-BiVO4 to further generate electron–hole pairs for photocatalytic degradation. Due to the special upconversion property of carbon nanodots, the carbon nanodots–m-BiVO4 nanospheres can be used as photocatalysts under the

• broad spectrum of sunshine. Based on a similar mechanism carbon nanodots can also be combined with Cu2O, Ag3PO4 or Fe2O3 for the photocatalytic degradation of methyl blue, methyl orange, and toxic gases of benzene and methanol, respectively [134][135][136]. The merits of carbon nanostructures, and

Effects of the preparation method on the structure and the visible-light photocatalytic activity of Ag₂CrO₄

• Difa Xu,
• Shaowen Cao,
• Jinfeng Zhang,
• Bei Cheng and
• Jiaguo Yu

Beilstein J. Nanotechnol. 2014, 5, 658–666, doi:10.3762/bjnano.5.77

• . The performance of the developed Ag2CrO4 is evaluated by the photocatalytic degradation of methylene blue under visible-light irradiation. The effect of the three preparation methods on the structure, optical properties and photocatalytic activity are investigated and discussed. Results and Discussion

• photocatalytic activity under visible-light irradiation. But it is not surprising that the rate constant for P25 is only 0.007 min−1 because the other phase anatase (75%) is not active in the visible region. Generally, the photocatalytic degradation of dyes in water is mainly attributed to the photogenerated

• holes, and the active oxygen species, including superoxide radicals (O2•−) and hydroxyl radicals (OH•). In order to understand the possible mechanism of the photocatalytic degradation of MB over Ag2CrO4, we have determined the CB and VB position at the point of zero charge by a widely accepted approach

Enhanced photocatalytic activity of Ag–ZnO hybrid plasmonic nanostructures prepared by a facile wet chemical method

• Sini Kuriakose,
• Vandana Choudhary,
• Biswarup Satpati and
• Satyabrata Mohapatra

Beilstein J. Nanotechnol. 2014, 5, 639–650, doi:10.3762/bjnano.5.75

• photocatalytic degradation efficiency, which has been found to increase with the extent of Ag nanoparticle loading. Keywords: Ag–ZnO; hybrid plasmonic nanostructures; photocatalysis; Introduction The removal of hazardous materials such as dyes and organic compounds from waste water has attracted ever

• increased efficiency for separation of photogenerated electrons and holes. It has been shown that Ag–ZnO nanostructures take 80 min for the complete photocatalytic degradation of 0.2 μM crystal violet dye under UV irradiation. Liu et al. [30] have studied the effects of Ag loading on ZnO on the

• photocatalytic degradation of rhodamine B (RhB) and showed that the degradation of RhB over pure Ag nanowires was negligible as compared to ZnO, the degradation efficiency of which further was increased due to the decoration with Ag nanoparticles. Deng et al. [19] fabricated Ag nanoparticles decorated ZnO

Mesoporous cerium oxide nanospheres for the visible-light driven photocatalytic degradation of dyes

• Subas K. Muduli,
• Songling Wang,
• Shi Chen,
• Chin Fan Ng,
• Cheng Hon Alfred Huan,
• Tze Chien Sum and
• Han Sen Soo

Beilstein J. Nanotechnol. 2014, 5, 517–523, doi:10.3762/bjnano.5.60

• reported for the purpose of the photocatalytic degradation of organic dyes and future applications in sustainable energy research. The earth-abundant, relatively affordable, mixed valence cerium oxide sample, which consists of predominantly Ce7O12, has been characterized by powder X-ray diffraction, X-ray

• photoelectron and UV–vis spectroscopy, and transmission electron microscopy. Together with N2 sorption experiments, the data confirms that the new cerium oxide material is mesoporous and absorbs visible light. The photocatalytic degradation of rhodamin B is investigated with a series of radical scavengers

• semiconductors have been explored for the visible-light driven photocatalytic degradation of pollutants and microbes, such as bismuth oxides [5][6] and cerium oxides [12][13]. CeO2 specifically has been applied in a number of sustainable energy applications lately, including oxidative catalysis, hydrogen storage

Applicability and costs of nanofiltration in combination with photocatalysis for the treatment of dye house effluents

• Wolfgang M. Samhaber and
• Minh Tan Nguyen

Beilstein J. Nanotechnol. 2014, 5, 476–484, doi:10.3762/bjnano.5.55

• high resistance to biological degradation. Dyes are made to be stable to light, oxidizing agents, and aerobic digestion to fulfil the quality demands of textile products. Fundamental principles and applications of photocatalytic degradation of dyes in homogeneous or heterogeneous systems can be found

• a major cost factor. The exclusive costs of NF will range from 1 to 6 US$ per m3 of treated effluent. But as a result, NF will ascertain high qualities of the treated effluents and can be synergistically combined with a photocatalytic degradation facility. General pre-treatment steps prior to

Study of mesoporous CdS-quantum-dot-sensitized TiO₂ films by using X-ray photoelectron spectroscopy and AFM

• Mohamed N. Ghazzal,
• Robert Wojcieszak,
• Gijo Raj and
• Eric M. Gaigneaux

Beilstein J. Nanotechnol. 2014, 5, 68–76, doi:10.3762/bjnano.5.6

• photosensitized solar cells with high quantum yields [1][2][3][4] and the photocatalytic degradation of pollutants [5][6]. CdS, currently used as an efficient visible-light sensitizer, is a semiconductor that possesses a small band gap (2.4 eV) and suitable potential energies. The electron transfer between QDs

Structural, optical and photocatalytic properties of flower-like ZnO nanostructures prepared by a facile wet chemical method

• Sini Kuriakose,
• Neha Bhardwaj,
• Jaspal Singh,
• Biswarup Satpati and
• Satyabrata Mohapatra

Beilstein J. Nanotechnol. 2013, 4, 763–770, doi:10.3762/bjnano.4.87

• these toxic chemicals. Photocatalytic degradation, in which the organic pollutants are degraded through photocatalytic oxidation and reduction reactions in the presence of a photocatalyst, is one of the most promising and clean processes used for water purification. Nanostructured semiconductor

• environmental pollutants. ZnO nanostructures with different morphologies have been synthesized by wet chemical methods [9][10][11][12][13] and used for various applications such as photocatalytic degradation of organic dyes [14][15][16][17][18][19][20][21][22][23][24], dye sensitized solar cells [25][26][27][28

• decrease in the efficiency of the sunlight driven photocatalytic degradation of MB. Results and Discussion Figure 1 shows the XRD patterns of the as-synthesized samples S1, S2 and S3 (see Experimental section for the naming scheme). The observed well-defined peaks in the spectra can be indexed to the

Modulation of defect-mediated energy transfer from ZnO nanoparticles for the photocatalytic degradation of bilirubin

• Tanujjal Bora,
• Karthik K. Lakshman,
• Soumik Sarkar,
• Abhinandan Makhal,
• Samim Sardar,
• Samir K. Pal and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2013, 4, 714–725, doi:10.3762/bjnano.4.81

• of the heme catabolism that can cause jaundice when its excretion is impaired. The photocatalytic degradation of BR activated by ZnO nanoparticles through a non-radiative energy transfer pathway can be influenced by the surface defect-states (mainly the oxygen vacancies) of the catalyst nanoparticles

• photocatalytic degradation and time-correlated single photon counting studies revealed that the defect-engineered ZnO nanoparticles that were obtained through post-annealing treatments led to an efficient decomposition of BR molecules that was enabled by Förster resonance energy transfer. Keywords: bilirubin

• molecular transformation of water-insoluble BR through photocatalysis is limited, a few studies are available on the photocatalytic degradation of BR adsorbed on nanostructured hydroxyapatite coatings [23] or molecularly imprinted titania films [24]. The current study focuses on the efficient utilization of

Paper modified with ZnO nanorods – antimicrobial studies

• Mayuree Jaisai,
• Sunandan Baruah and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2012, 3, 684–691, doi:10.3762/bjnano.3.78

• offer large surface-to-volume ratios. Hydrothermally grown ZnO nanorods possess inherent defects in the form of oxygen vacancies and zinc interstitials, which shift its optical absorption from the ultraviolet to the visible region [20]. We previously reported the visible-light photocatalytic degradation

Mesoporous MgTa₂O₆ thin films with enhanced photocatalytic activity: On the interplay between crystallinity and mesostructure

• Jin-Ming Wu,
• Igor Djerdj,
• Till von Graberg and
• Bernd M. Smarsly

Beilstein J. Nanotechnol. 2012, 3, 123–133, doi:10.3762/bjnano.3.13

• films. Photocatalytic degradation of RhB in water roughly follows a pseudo-first-order reaction [22][23][24], where c/c0 is the normalized RhB concentration, t is the illumination time, and k is the apparent reaction rate in terms of min−1. All of the data demonstrated good linearity for all the curves

Self-assembled monolayers and titanium dioxide: From surface patterning to potential applications

• Yaron Paz

Beilstein J. Nanotechnol. 2011, 2, 845–861, doi:10.3762/bjnano.2.94

• ; Introduction Photocatalytic degradation of pollutants is attracting increasing attention. In this context, anatase-phase titanium dioxide is regarded as the photocatalyst of choice, due to its low cost, nontoxicity, and relatively high efficiency, which make it suitable not only for air and water

• are trapped by H2O or OH– adsorbed at the surface, thus forming hydroxyl radicals. In parallel, the electrons reduce adsorbed oxygen [4] to form superoxide radicals. The first step in the photocatalytic degradation of most organic compounds is an oxidative attack by the hydroxyl radicals, which

• many ways, from the study of fundamental issues in TiO2 photocatalysis to the growth of supramolecular structures; from serving as a tool for patterning to suggesting means to obtain the selective photocatalytic degradation of highly toxic contaminants. This potential for synergism between self

Enhanced visible light photocatalysis through fast crystallization of zinc oxide nanorods

• Sunandan Baruah,
• Mohammad Abbas Mahmood,
• Myo Tay Zar Myint,
• Tanujjal Bora and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2010, 1, 14–20, doi:10.3762/bjnano.1.3

• crystallization temperatures, homogenous nucleation and fast supersaturation by rapid dissolution [22][23][24][25][26][27]. In this work a study is conducted on the improvement of visible light photocatalytic degradation of a model organic dye, methylene blue, with ZnO nanorods grown by a rapid growth process

• (3 cm2). The photocatalytic degradation of MB could be fitted using Equation 2 and the apparent rate constants (k = ab) were calculated from the linear curves using Equation 3: The nanoparticle film demonstrated minimum photocatalytic activity as expected owing to lower surface (SA ≈ 6 cm2) exposed

• . Comparative results of photocatalytic degradation studies on methylene blue with visible light irradiation demonstrated that ZnO nanorods are 12–24% more active than nanoparticulate films. An enhancement of 8% in the photocatalytic activity of ZnO nanorods was achieved through engineered creation of oxygen