A single-source precursor route to anisotropic halogen-doped zinc oxide particles as a promising candidate for new transparent conducting oxide materials

• Daniela Lehr,
• Markus R. Wagner,
• Johanna Flock,
• Julian S. Reparaz,
• Clivia M. Sotomayor Torres,
• Alexander Klaiber,
• Thomas Dekorsy and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2015, 6, 2161–2172, doi:10.3762/bjnano.6.222

• indispensable constituents in important technological devices such as flat panel displays, touch screens, solar cells and photocatalytic systems [1][2][3][4]. Among the different materials used for this purpose [5] such as carbon nanostructures [6][7][8], silver nanowires [9][10] or conducting polymers [11

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

• effect of the thickness of the silicon nitride (SiNx) diffusion barrier on the structural and photocatalytic efficiency of TiO2 films obtained with different processes. We show that the structural and photocatalytic efficiency of TiO2 films produced using soft chemistry (sol–gel) and physical methods

• showed no dependence on the thickness of the SiNx barrier diffusion. The SiNx barrier diffusion showed a beneficial effect on the photocatalytic efficiency of TiO2 films regardless of the synthesis method used. The proposed mechanism leading to the improvement in the photocatalytic efficiency of the TiO2

• required in order to obtain the photoactive anatase phase. However, Na+ ions have a detrimental effect on the photocatalytic efficiency of TiO2 [3][4][7]. The poisoning effect of the Na+ ions on the photocatalytic activity occurs in different ways and depends on their concentration, for example: (a) Na

Temperature-dependent breakdown of hydrogen peroxide-treated ZnO and TiO₂ nanoparticle agglomerates

• Sinan Sabuncu and
• Mustafa Çulha

Beilstein J. Nanotechnol. 2015, 6, 1897–1903, doi:10.3762/bjnano.6.193

• photocatalytic activity of the NPs [23]. The objective of this study is to disintegrate MONP agglomerates using heat and H2O2 treatment without the use of any additional chemicals. ZnO and TiO2 NPs were chosen due to their widespread use in several industrial applications. The H2O2 treatment not only eliminates

Radiation losses in the microwave K_u band in magneto-electric nanocomposites

• Talwinder Kaur,
• Sachin Kumar,
• Jyoti Sharma and
• A. K. Srivastava

Beilstein J. Nanotechnol. 2015, 6, 1700–1707, doi:10.3762/bjnano.6.173

• interesting material with variable properties and a large anisotropy field having a magnetic resonance in the range of 2–52 GHz. Also, at the nano-scale, its optical properties [19], magnetic properties [20][21], piezo-electric properties [22], photocatalytic properties [23], gas-sensing properties [24

High photocatalytic activity of V-doped SrTiO₃ porous nanofibers produced from a combined electrospinning and thermal diffusion process

• Panpan Jing,
• Wei Lan,
• Qing Su and
• Erqing Xie

Beilstein J. Nanotechnol. 2015, 6, 1281–1286, doi:10.3762/bjnano.6.132

• uniform, porous, fibrous structure, but also that some V5+ ions are introduced into the SrTiO3 lattice. The photocatalytic capability of V-doped SrTiO3 porous nanofibers was evaluated through photodegrading methyl orange (MO) in aqueous solution under artificial UV–vis light. The results indicated that V

• -doped SrTiO3 porous nanofibers have excellent catalytic efficiency. Furthermore, the excellent catalytic activity was maintained even after five cycle tests, indicating that they have outstanding photocatalytic endurance. It is suggested that the excellent photocatalytic performance of doped SrTiO3

• species, such as hydroxyl radicals (·OH) and superoxide anions (O2−). Since Fujishima and Honda first reported photo-electrochemical water splitting using a TiO2 electrode [7], many studies have been carried out on photocatalytic pollutant removal and electronic structures of semiconductors containing d0

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

• absorption spectroscopy and Raman spectroscopy. XRD studies showed the presence of ZnO and CuO nanostructures in the nanocomposites. FESEM images revealed the presence of nanosheets and nanorods in the nanocomposites. The photocatalytic activity of ZnO–CuO nanocomposites was evaluated on the basis of

• degradation of methylene blue (MB) and methyl orange (MO) dyes under sun light irradiation and it was observed that swift heavy ion irradiation results in significant enhancement in the photocatalytic efficiency of ZnO–CuO nanocomposites towards degradation of MB and MO dyes. The possible mechanism for the

• enhanced photocatalytic activity of ZnO–CuO nanocomposites is proposed. We attribute the observed enhanced photocatalytic activity of ZnO–CuO nanocomposites to the combined effects of improved sun light utilization and suppression of the recombination of photogenerated charge carriers in ZnO–CuO

Transformation of hydrogen titanate nanoribbons to TiO₂ nanoribbons and the influence of the transformation strategies on the photocatalytic performance

• Melita Rutar,
• Nejc Rozman,
• Matej Pregelj,
• Carla Bittencourt,
• Romana Cerc Korošec,
• Andrijana Sever Škapin,
• Aleš Mrzel,
• Srečo D. Škapin and
• Polona Umek

Beilstein J. Nanotechnol. 2015, 6, 831–844, doi:10.3762/bjnano.6.86

• spectroscopy. According to electron paramagnetic resonance measurements the calcination in the reductive atmosphere also resulted in a partial reduction of Ti4+ to Ti3+. The photocatalytic performance of the derived TiO2 NRs was estimated on the basis of the photocatalytic oxidation of isopropanol. After

• calcinating in air, the photocatalytic performance of the investigated TiO2 NRs increased with an increased content of anatase. In contrast, the photocatalytic performance of the N-doped TiO2 NRs showed no dependence on the calcination temperature. An additional comparison showed that the N-doping

• significantly suppressed the photocatalytic performance of the TiO2 NRs, i.e., by 3 to almost 10 times, in comparison with the TiO2 NRs derived by calcination in air. On the other hand, the photocatalytic performance of the hydrothermally derived TiO2 NRs was additionally improved by a subsequent heat treatment

Morphological and structural characterization of single-crystal ZnO nanorod arrays on flexible and non-flexible substrates

• Omar F. Farhat,
• Mohd M. Halim,
• Mat J. Abdullah,
• Mohammed K. M. Ali and
• Nageh K. Allam

Beilstein J. Nanotechnol. 2015, 6, 720–725, doi:10.3762/bjnano.6.73

• , and nanoneedles, among many other forms [3][4][5]. However, the majority of the resulting structures are amorphous and require high-temperature heat treatment to induce crystallinity. The need for heat treatment limits their use with temperature-sensitive materials, such polymeric photocatalytic

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 with a predominant rutile phase. The photodegradation of methylene blue showed that this pyrochlore phase enhanced the photocatalytic activity of the rutile phase. Keywords: nanoparticles; photocatalysis; pyrochlore; titanium dioxide; thulium; Introduction TiO2 is one of the most efficient

• semiconductors used as a photocatalyst for the degradation of organic compounds. This is due to its high chemical and biological stability, low cost, excellent electronic and optical properties, and the strong oxidation capacity of its photogenerated holes [1][2]. Photocatalytic activity depends on several

• [5]. TiO2 doping with metallic elements has also been reported, using for example niobium [6], silver [7] or copper [8] as dopants. Many pyrochlore-type compounds (A2B2O7) have been studied to evaluate their semiconductor properties for photocatalytic applications. For example, it is possible to find

Novel ZnO:Ag nanocomposites induce significant oxidative stress in human fibroblast malignant melanoma (Ht144) cells

• Syeda Arooj,
• Samina Nazir,
• Akhtar Nadhman,
• Nafees Ahmad,
• Bakhtiar Muhammad,
• Ishaq Ahmad,
• Kehkashan Mazhar and
• Rashda Abbasi

Beilstein J. Nanotechnol. 2015, 6, 570–582, doi:10.3762/bjnano.6.59

• .6.59 Abstract The use of photoactive nanoparticles (NPs) such as zinc oxide (ZnO) and its nanocomposites has become a promising anticancer strategy. However, ZnO has a low photocatalytic decomposition rate and the incorporation of metal ions such as silver (Ag) improves their activity. Here different

• . The NPs were investigated with regard to their different photocatalytic cytotoxic effects in human malignant melanoma (HT144) and normal (HCEC) cells. The ZnO:Ag nanocomposites killed cancer cells more efficiently than normal cells under daylight exposure. Nanocomposites having higher Ag content (10

• photocatalytic decomposition process is slow and needs to be improved [24]. Therefore, it is interesting to enhance their photocatalytic ability and anticancer activity by forming nanocomposites with other materials, including metal ions such as silver (Ag) or iron (Fe) ions [25]. The ZnO:Ag nanocomposites

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

• with controlled Pd NPs size ranging between 17 and 29 nm onto the surface of TiO2. Thus, it gives the characteristic for Pd NPs to absorb light in the visible region obtained through localized surface plasmon resonance (LSPRs). Apparently, the photocatalytic activity of the prepared photocatalysts was

• reusability trend proved the photostability of the prepared photocatalysts. Hence, the study provides a new insight about the modification of TiO2 with noble metals in order to enhance the absorption in the visible-light region for superior photocatalytic performance. Keywords: endocrine disrupting compound

• ; nano photocatalysts; noble metal; photodeposition; sunlight; Introduction Heterogeneous photocatalysts that employ TiO2 as metal oxide photocatalyst have raised the interest of many researchers since the discovery of the photocatalytic splitting of water under UV light irradiation by Fujishima and

Interaction of dermatologically relevant nanoparticles with skin cells and skin

• Annika Vogt,
• Fiorenza Rancan,
• Sebastian Ahlberg,
• Berouz Nazemi,
• Chun Sik Choe,
• Maxim E. Darvin,
• Sabrina Hadam,
• Ulrike Blume-Peytavi,
• Kateryna Loza,
• Jörg Diendorf,
• Matthias Epple,
• Christina Graf,
• Eckart Rühl,
• Martina C. Meinke and
• Jürgen Lademann

Beilstein J. Nanotechnol. 2014, 5, 2363–2373, doi:10.3762/bjnano.5.245

• cause particle disintegration leading to a reduction of the size of the particles with an increased likelihood of penetration [32] or it can trigger photocatalytic processes which cause secondary harm to skin cells [33][34]. Identification of factors which influence cellular uptake In our studies, the

Inorganic Janus particles for biomedical applications

• Isabel Schick,
• Steffen Lorenz,
• Dominik Gehrig,
• Stefan Tenzer,
• Wiebke Storck,
• Karl Fischer,
• Dennis Strand,
• Frédéric Laquai and
• Wolfgang Tremel

Beilstein J. Nanotechnol. 2014, 5, 2346–2362, doi:10.3762/bjnano.5.244

• d) embedding of the final hybrid particle at the interface in a PS-PMMA blend. Reprinted with permission from [34]. Copyright 2013 Elsevier. a) Proposed photocatalytic process for efficient hydrogen generation using the Janus Au@TiO2 nanostructures, based on excitation of the LSPR under visible

Influence of stabilising agents and pH on the size of SnO₂ nanoparticles

• Olga Rac,
• Patrycja Suchorska-Woźniak,
• Marta Fiedot and
• Helena Teterycz

Beilstein J. Nanotechnol. 2014, 5, 2192–2201, doi:10.3762/bjnano.5.228

• dioxide; Introduction Tin dioxide is an n-type semiconductor with a band gap width of 3.6 eV. It is characterised by good photocatalytic properties and in its presence, decomposition of an organic dye in the visible range of the electromagnetic spectrum may takes place [1]. Moreover, SnO2 is widely used

• loss of the typical characteristic properties of nanomaterials, for example, the specific sensor or photocatalytic properties. For this reason, colloidal metal oxide nanoparticles (regardless of the synthesis method) require the use of a stabilising agent to fully maintain a high state of dispersion

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

Rapid degradation of zinc oxide nanoparticles by phosphate ions

• Rudolf Herrmann,
• F. Javier García-García and
• Armin Reller

Beilstein J. Nanotechnol. 2014, 5, 2007–2015, doi:10.3762/bjnano.5.209

• recently [23]. Special attention to the effects of phosphate around neutral pH has been payed only very recently [24]. The photocatalytic activity of ZnO nanoparticles can be significantly reduced by coating with SiO2 [25]. This is important when ZnO-NP are applied as UV blockers. We therefore also

• phosphate buffers. Photocatalytic activity of ZnO-NP, e.g., in oxidation reactions, is an unwanted feature when they are to be applied as UV blockers. Among the suggested coatings, which should block this activity, silica is mostly used in commercial preparations [25]. In principle, coatings should also

• zinc phosphate, which does not lead to precipitation and equilibrium shifts. In the light of these results it seems essential to ensure a tight coating by a chemically resistant material before applying ZnO-NP for, e.g., medical or cosmetic purposes. Silica coating can suppress photocatalytic activity

Synthesis of hydrophobic photoluminescent carbon nanodots by using L-tyrosine and citric acid through a thermal oxidation route

• Venkatesh Gude

Beilstein J. Nanotechnol. 2014, 5, 1513–1522, doi:10.3762/bjnano.5.164

• -sensor [11][12], and photocatalytic applications [13][14]. CNDs that possess a conjugated conducting network of predominantly sp2-hybridized carbon atoms with only a little amount of sp3-hybridized carbon atoms, along with a distribution of some atoms such as oxygen and nitrogen are sometimes referred to

• ], photocatalytic applications [28][29]. Very few reports about hydrophobic CNDs are known [30][31]. Hydrophobic fluorescent probes (e.g., Nile red) were found to be useful for labeling hydrophobic environments in bacteria [32], but the problem associated with organic dyes is photobleaching. CNDs are promising

Enhanced photocatalytic hydrogen evolution by combining water soluble graphene with cobalt salts

• Jing Wang,
• Ke Feng,
• Hui-Hui Zhang,
• Bin Chen,
• Zhi-Jun Li,
• Qing-Yuan Meng,
• Li-Ping Zhang,
• Chen-Ho Tung and
• Li-Zhu Wu

Beilstein J. Nanotechnol. 2014, 5, 1167–1174, doi:10.3762/bjnano.5.128

• , Beijing 100190, P. R. China 10.3762/bjnano.5.128 Abstract There is tremendous effort put in the pursuit for cheap and efficient catalysts for photocatalytic hydrogen evolution systems. Herein, we report an active catalyst that uses the earth-abundant element cobalt and water-dispersible sulfonated

• graphene. The photocatalytic hydrogen evolution activity of the catalyst was tested by using triethanolamine (TEOA) as electron donor and eosin Y (EY) as the photosensitizer under LED irradiation at 525 nm. Hydrogen was produced constantly even after 20 h, and the turnover number (TON) reached 148 (H2/Co

• ) in 4 h with respect to the initial concentration of the added cobalt salts was shown to be 5.6 times larger than that without graphene. Keywords: cobalt salts; earth-abundant catalyst; photocatalysis; photocatalytic hydrogen evolution; water-dispersible sulfonated-graphene; Introduction

Organic and inorganic–organic thin film structures by molecular layer deposition: A review

• Pia Sundberg and
• Maarit Karppinen

Beilstein J. Nanotechnol. 2014, 5, 1104–1136, doi:10.3762/bjnano.5.123

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

• characterized by various techniques such as TGA-DTA-DSC, UV–vis DRS, XRD, SEM, TEM, particle size analyzer (DLS) and the Brunauer–Emmett–Teller (BET) method. The band gap of the particles was calculated by using the Tauc plot. The photocatalytic activity of Ta2O5 nanoparticles was tested by the degradation of

• to its distinct properties such as large ion diffusion coefficient and high electrochromic reversibility, high dielectric constant, high refractive index, high chemical stability, large band gap [13][14][15] and photocatalytic activity for overall water decomposition and organic pollutant degradation

• (1) was isolated. When 1 was subjected to further hydrolysis it yielded nanoparticles of tantalum oxide after calcination at 750 °C for four hours. The photocatalytic activity of Ta2O5 nanoparticles was studied over the degradation of organic dye rhodamine B (RhB). Results and Discussion Tantalum

Photocatalysis

• Rong Xu

Beilstein J. Nanotechnol. 2014, 5, 1071–1072, doi:10.3762/bjnano.5.119

• , two review articles present an excellent overview of the significance of nanostructures in visible light photocatalysis in a timely manner. Many materials aspects of photocatalysts influence the photocatalytic performance, such as the electronic, structural, and morphological features of the

• degradation. In recent years, the interest in photocatalytic organic conversion has risen, which is reflected by a report on photo-epoxidation. And last but not least, one of the studies of this Thematic Series aims for a fundamental understanding of the photophysical process by optical modeling. I am

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

Functionalized nanostructures for enhanced photocatalytic performance under solar light

• Liejin Guo,
• Dengwei Jing,
• Maochang Liu,
• Yubin Chen,
• Shaohua Shen,
• Jinwen Shi and
• Kai Zhang

Beilstein J. Nanotechnol. 2014, 5, 994–1004, doi:10.3762/bjnano.5.113

• Liejin Guo Dengwei Jing Maochang Liu Yubin Chen Shaohua Shen Jinwen Shi Kai Zhang International Research Center for Renewable Energy & State Key Laboratory of Multiphase Flow in Power Engineering, Xi’an Jiaotong University Xi’an 710049, China 10.3762/bjnano.5.113 Abstract Photocatalytic hydrogen

• production from water has been considered to be one of the most promising solar-to-hydrogen conversion technologies. In the last decade, various functionalized nanostructures were designed to address the primary requirements for an efficient photocatalytic generation of hydrogen by using solar energy

• nanoscale, i.e., materials with the same compositions but different phases with certain band alignment. We conclude this review with perspectives on nanostructure design that might direct future research of this technology. Keywords: functionalized nanostructures; hydrogen; photocatalysis; photocatalytic

Growth and characterization of CNT–TiO₂ heterostructures

• Yucheng Zhang,
• Ivo Utke,
• Johann Michler,
• Gabriele Ilari,
• Marta D. Rossell and
• Rolf Erni

Beilstein J. Nanotechnol. 2014, 5, 946–955, doi:10.3762/bjnano.5.108

• , combining TiO2 nanocrystals and carbon nanotubes (CNTs) offers enhanced photosensitivity and improved photocatalytic efficiency, which is key to achieving sustainable energy and preventing environmental pollution. Hence, it has aroused a tremendous research interest. This report surveys recent research on

• discovery that with the addition of CNTs, the light absorption of TiO2 can be extended to the visible-light region [8][9][10][11][12][13][14]. This can significantly increase the photocatalytic efficiency. In literature several photocatalysis enhancement mechanisms based on TiO2–CNT have been proposed, as

• photocatalytic performance than the chemical bond between CNTs and TiO2, since the arc-discharge-synthesized CNTs show a dramatically higher photocatalytic dye degradation rate than the CVD-synthesized CNTs, which is attributed to the smaller number of defects in the multi-wall (MW) tubes of the former. In

Enhancement of photocatalytic H₂ evolution of eosin Y-sensitized reduced graphene oxide through a simple photoreaction

• Weiying Zhang,
• Yuexiang Li,
• Shaoqin Peng and
• Xiang Cai

Beilstein J. Nanotechnol. 2014, 5, 801–811, doi:10.3762/bjnano.5.92

• hydroxy groups are gradually removed from GO, resulting in an increase of sp2 π-conjugated domains and defect carbons with holes for the formed RGO. The RGO conductivity increases due to the restoration of sp2 π-conjugated domains. The photocatalytic activity of EY-RGO/Pt for hydrogen evolution was

• increasing irradiation time. The adsorption quantity of EY on the surface of RGO enhances, too. The two factors ultimately result in an enhancement of the photocatalytic hydrogen evolution over EY-RGO/Pt with increasing irradiation time. A possible mechanism is discussed. Keywords: eosin Y sensitization

• ; graphene oxide; H2 evolution; photocatalysis; photoreduction; sp2 conjugated domains; Introduction Hydrogen is an efficient and green energy carrier. Photocatalytic water splitting into hydrogen by means of solar energy and semiconductor photocatalysts is a environmentally friendly way to produce storable