Optical modeling-assisted characterization of dye-sensitized solar cells using TiO₂ nanotube arrays as photoanodes

• Jung-Ho Yun,
• Il Ku Kim,
• Yun Hau Ng,
• Lianzhou Wang and
• Rose Amal

Beilstein J. Nanotechnol. 2014, 5, 895–902, doi:10.3762/bjnano.5.102

• , 78.6, and 98.7 nm, respectively. The longest TNT array of 20.6 μm in length showed enhanced photovoltaic performances of 3.87% with significantly increased photocurrent density of 8.26 mA·cm−2. This improvement is attributed to the increased amount of the adsorbed dyes and the improved electron

• the electrolyte layer and the Pt deposited FTO glass in the counter electrode through back side illumination [20]. The steady increase in IPCE with longer tube lengths is attributed to the increase in Jsc by the increased amount of dyes adsorbed on the longer TNT arrays, followed by a further increase

• steps using a Keithley 2400 source measure unit. The amount of adsorbed dye concentration was determined by measuring the absorbance of dye solution desorbed from the surface of the TNT array in basic solution. In order to desorb dyes, N719 dye-adsorbed TNT arrays were immersed in a 0.1 M NaOH in water

Pyrite nanoparticles as a Fenton-like reagent for in situ remediation of organic pollutants

• Carolina Gil-Lozano,
• Elisabeth Losa-Adams,
• Alfonso F.-Dávila and
• Luis Gago-Duport

Beilstein J. Nanotechnol. 2014, 5, 855–864, doi:10.3762/bjnano.5.97

• remains poorly studied and, to the best of our knowledge, has never been used to remove dyes from textile wastewater. In this work, we compared synthetic pyrite nanoparticles to naturally derived pyrite microparticles for their efficiency in the oxidative degradation of copper phthalocyanine (CuPc), a

• a cheap alternative to conventional Fenton approaches for the selective oxidation of pollutant dyes. Experimental Chemicals Copper phthalocyanine-3, 4´, 4´´, 4´´´- tetrasulfonic acid tetrasodium salt (85%), oleylamine (OA, 70%), sulfur (99.99%) and toluene (99.8% anhydrous) were purchased from Sigma

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

• as photosensitizers for transition metal oxides. Note that various organic dyes such as rhodamine B, porphyrins, and phthalocyanines have been employed as photosensitizers [11][12][13][14] and these dyes also play an important role in the photosensitization of dye-sensitized solar cells (DSSCs) [15

• carriers, quantum dots have a unique photoluminescence (PL). In comparison with organic dyes, quantum dots are characterized by unique optical and electronic properties such as a higher PL quantum efficiency, a wide continuous absorption, a narrower PL band, tunable luminescence depending only on their

• dyes or quantum dots, the plasmonic metal nanostructures can also be used as photosensitizer to effectively improve the visible-light response of transition metal oxides, which yields novel heterostructures of plasmonic metal photosensitized photocatalysts with a variety of applications including DSSC

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

• 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

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

• increasing attention over the years. Semiconductor photocatalysis is one of the most important technologies used for the complete mineralization of a wide range of organic dyes and toxic chemicals. ZnO, a wide band gap semiconductor with large excitonic binding energy is suitable for diverse applications

• nanostructures of various morphology have shown considerable increase in the photocatalytic efficiency for the degradation of organic dyes [19][23][29][30][31][32][33][34]. Xie et al. [23] have shown that Ag loading on ZnO nanostructures improves its photostability and enhances the photocatalytic activity due to

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

• nanospheres, which is a mixed phase of Ce7O12 and CeO2, and can absorb visible light to photocatalytically degrade dyes such as rhodamine B (RhB). The materials characterization of the cerium oxide nanospheres and some mechanistic insights into the photocatalytic process are presented. Findings

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

• Nanofiltration (NF) is a capable method for the separation of dyes, which can support and even improve the applicability of photocatalysis in effluent-treatment processes. The membrane process usually will need a special pre-treatment to avoid precipitation and fouling on the membrane surface. Conceptually NF

• 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

• Conventional concepts of effluent treatment and NF In the conventional treatment of effluent of the textile industries separation methods like coagulation, flocculation, flotation or sedimentation are used. Process variants concerning the separation of dyes are numerous, but all of them require a final

Dye-sensitized Pt@TiO₂ core–shell nanostructures for the efficient photocatalytic generation of hydrogen

• Jun Fang,
• Lisha Yin,
• Shaowen Cao,
• Yusen Liao and
• Can Xue

Beilstein J. Nanotechnol. 2014, 5, 360–364, doi:10.3762/bjnano.5.41

• hydrothermal method. The dye-sensitization of these Pt@TiO2 core–shell structures allows for a high photocatalytic activity for the generation of hydrogen from proton reduction under visible-light irradiation. When the dyes and TiO2 were co-excited through the combination of two irradiation beams with

• Grätzel in 1991 [12], various types of dyes have been explored, and some of them allow for the reduction of protons into hydrogen gas through visible-light-driven photocatalytic processes [13][14][15][16][17]. Herein, we use erythrosin B (ErB) sensitized Pt@TiO2 core–shell nanoparticles for the highly

Near-infrared dye loaded polymeric nanoparticles for cancer imaging and therapy and cellular response after laser-induced heating

• Tingjun Lei,
• Alicia Fernandez-Fernandez,
• Romila Manchanda,
• Yen-Chih Huang and
• Anthony J. McGoron

Beilstein J. Nanotechnol. 2014, 5, 313–322, doi:10.3762/bjnano.5.35

• that combine imaging and therapeutic agents. In our study, we use a new biocompatible and biodegradable polymer, termed poly(glycerol malate co-dodecanedioate) (PGMD), for the synthesis of nanoparticles (NPs) and loading of near-infrared (NIR) dyes. IR820 was chosen for the purpose of imaging and

• synthesis of PGMD polymer, PGMD NPs were also successfully formulated. Optical imaging has several advantages over more traditional imaging techniques (MRI, PET, CT, etc.), such as high spatial resolution, real time imaging, and systems that are usually smaller and less expensive. Near-infrared imaging dyes

• (wavelength 700–900 nm) are promising for in vivo imaging because light at these wavelengths has minimal absorption by tissue [6][7]. Moreover, some NIR dyes such as indocyanine green (ICG) can be used as both imaging agents and heat generators due to their unique photothermal properties. However, ICG has a

Dye-doped spheres with plasmonic semi-shells: Lasing modes and scattering at realistic gain levels

• Nikita Arnold,
• Boyang Ding,
• Calin Hrelescu and
• Thomas A. Klar

Beilstein J. Nanotechnol. 2013, 4, 974–987, doi:10.3762/bjnano.4.110

• scatter light preferentially into certain directions [15][16]. Recently, we have shown that localized plasmonic modes of the semi-shells are apt to direct the fluorescence from the dyes contained in their dielectric cores into the forward direction [17]. Plasmonic semi-shells or nanovoids have also been

• the scattering component of the OD. The concentration of the spheres was quantified by measuring the scattering strength at a wavelength far from the absorption of the dyes. From this, we estimated an absorption constant in the range of 2300 cm−1, which translates into a transition strength of ΔεDye

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

• efficiency to photocatalytically degrade of MB. Keywords: ageing; nanoparticles; nanosheets; photocatalysis; ZnO; Introduction Water contamination due to hazardous water soluble organic dyes and chemicals poses a severe threat to the environment. The excess azo dyes in effluents from textile and dyeing

• treatment, these azo dyes may generate carcinogenic compounds such as aromatic amines. Because of this, purification and detoxification of industrial waste water has been one of the major challenges. Several methods such as adsorption, filtration, sedimentation and photocatalysis are used for the removal of

• dyeing industries. Since the sun is an abundantly available natural energy source, its light can be conveniently utilized for the photodegradation of organic dyes [3][4][5][6][7][8]. ZnO with a band gap of 3.37 eV has received much attention for the complete mineralization and degradation of

Optimization of solution-processed oligothiophene:fullerene based organic solar cells by using solvent additives

• Gisela L. Schulz,
• Marta Urdanpilleta,
• Roland Fitzner,
• Eduard Brier,
• Elena Mena-Osteritz,
• Egon Reinold and
• Peter Bäuerle

Beilstein J. Nanotechnol. 2013, 4, 680–689, doi:10.3762/bjnano.4.77

• [6], phthalocyanines [7], and squarine dyes [8][9] have all been investigated as promising donor materials in efficient BHJSCs. Power conversion efficiencies (PCEs) up to 6.9% have been reported for oligomers based on vacuum-processed [10] and 8.2% for solution-processed single junction devices [11

Apertureless scanning near-field optical microscopy of sparsely labeled tobacco mosaic viruses and the intermediate filament desmin

• Alexander Harder,
• Mareike Dieding,
• Volker Walhorn,
• Sven Degenhard,
• Andreas Brodehl,
• Christina Wege,
• Hendrik Milting and
• Dario Anselmetti

Beilstein J. Nanotechnol. 2013, 4, 510–516, doi:10.3762/bjnano.4.60

• versatile and extensively used in applications ranging from nanotechnology to life sciences. In fluorescence microscopy luminescent dyes serve as position markers. Moreover, they can be used as active reporters of their local vicinity. The dipolar coupling of the tip with the incident light and the

• in such a way that we gain two fluorescence images corresponding to both reversal points of the cantilever oscillation (Figure 2b). The gating window corresponds to a phase width of 20–40°. Modified TMV with sparsely distributed fluorescent dyes, which label selectively addressable groups, were

• , the optical SNR was better than 10 for all analyzed dyes, which corresponds nicely to recently published results [5]. It is noteworthy that the resolution for individual fluorophores can differ significantly (Figures 3, 4 and 5) from the average. This is most probably due to the comparably high

Kelvin probe force microscopy of nanocrystalline TiO₂ photoelectrodes

• Alex Henning,
• Gino Günzburger,
• Res Jöhr,
• Yossi Rosenwaks,
• Biljana Bozic-Weber,
• Catherine E. Housecroft,
• Edwin C. Constable,
• Ernst Meyer and
• Thilo Glatzel

Beilstein J. Nanotechnol. 2013, 4, 418–428, doi:10.3762/bjnano.4.49

• with a tunable illumination system. A comparison of the surface potentials for TiO2 photoelectrodes sensitized with two different dyes, i.e., the standard dye N719 and a copper(I) bis(imine) complex, reveals an inverse orientation of the surface dipole. A higher surface potential was determined for an

• electrons diffuse toward the SnO2:F substrate and establish the photovoltage. The most frequently used dye complexes contain less-abundant transition metal elements such as ruthenium. Complexes of earth-abundant metals such as zinc and copper are candidates to replace the more expensive ruthenium dyes [9

• higher for an N719 sensitized TiO2 photoelectrode and about 180 mV lower for Cu-dye sensitized TiO2 resulting in a 200 mV higher open-circuit voltage (Voc) for a complete N719 DSC. We conclude that the surface dipole orientation is inverted for the two dyes and the Voc of a complete DSC increases with a

Porous polymer coatings as substrates for the formation of high-fidelity micropatterns by quill-like pens

• Michael Hirtz,
• Marcus Lyon,
• Wenqian Feng,
• Andrea E. Holmes,
• Harald Fuchs and
• Pavel A. Levkin

Beilstein J. Nanotechnol. 2013, 4, 377–384, doi:10.3762/bjnano.4.44

• -hydroxyethyl methacrylate-co-ethylene dimethacrylate) support (HEMA) with narrow pore size distribution in the 150 nm range, which demonstrated advantages in pattern definition, spot homogeneity, and consistent spot delivery of different dyes (phloxine B and bromophenol blue) with diameters of several

• –50 micrometer sized spots inside a HEMA film, using quill-like microcantilevers. In contrast to nonporous substrates, porous films allow for the noncovalent infiltration of fluorescent sensors or dyes that can accommodate a greater volume and increased surface area for analyte binding. This should

Near-field effects and energy transfer in hybrid metal-oxide nanostructures

• Ulrich Herr,
• Barat Achinuq,
• Cahit Benel,
• Giorgos Papageorgiou,
• Manuel Goncalves,
• Johannes Boneberg,
• Paul Leiderer,
• Paul Ziemann,
• Peter Marek and
• Horst Hahn

Beilstein J. Nanotechnol. 2013, 4, 306–317, doi:10.3762/bjnano.4.34

• fluorescent dyes on silica-protected Au nanoantennas by Fayyaz et al. [21], where the silica film thickness was varied between 5 and 25 nm. The resulting fluorescence images of our samples for excitation with 532 nm radiation are shown in Figure 22 in comparison with the fluorescence images of noncoated

Photoelectrochemical and Raman characterization of In₂O₃ mesoporous films sensitized by CdS nanoparticles

• Mikalai V. Malashchonak,
• Sergey K. Poznyak,
• Eugene A. Streltsov,
• Anatoly I. Kulak,
• Olga V. Korolik and
• Alexander V. Mazanik

Beilstein J. Nanotechnol. 2013, 4, 255–261, doi:10.3762/bjnano.4.27

• . Keywords: cadmium sulfide (CdS); indium oxide (In2O3); nanoparticles; successive ionic layer adsorption and reaction (SILAR); Introduction In third-generation solar cells molecular dyes (in the Grätzel cells [1]) as well as nanoparticles of semiconducting metal chalcogenides (CdS, CdSe, CdTe, PbS, PbSe

• ionic layer adsorption and reaction (SILAR) method [6][7][8][9][10][11], which allows the precise control of the growth of the nanoparticles. To efficiently inject electrons from the photo-excited semiconductor nanoparticles or molecular dyes into the oxide matrix, the energy of the oxide conduction

Selective surface modification of lithographic silicon oxide nanostructures by organofunctional silanes

• Thomas Baumgärtel,
• Christian von Borczyskowski and
• Harald Graaf

Beilstein J. Nanotechnol. 2013, 4, 218–226, doi:10.3762/bjnano.4.22

• fluorescence signal is comparably weak (roughly a factor of 10 above the background noise level). The main reason for this is the quenching by the underlying silicon. Nevertheless, other high-quantum-yield xanthene dyes (e.g., rhodamine 6G) that are bound to the nanostructures by electrostatic interactions

• difference in fluorescence intensity between the electrostatically bound dyes and the covalently bound FITC is a much lower surface density in the case of covalently bound FITC. Of course this conclusion, though plausible, is based on many uncertainties and assumptions. Yet a more precise quantification is

• very difficult due to the unknown quenching by the underlying silicon and the unavailability of suitable measurement techniques of the surface coverage for such small geometries. If the density of FITC molecules on the structures is really much lower than that of electrostatically attracted dyes then

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

• of organic dyes using similar paper embedded with ZnO nanorods [21]. In this work we report the antimicrobial activities of paper functionalized by in situ growth of ZnO nanorods through a hydrothermal process. Results and Discussion Studies on the photocatalytic immobilization of E. coli and S

Horizontal versus vertical charge and energy transfer in hybrid assemblies of semiconductor nanoparticles

• Gilad Gotesman,
• Rahamim Guliamov and
• Ron Naaman

Beilstein J. Nanotechnol. 2012, 3, 629–636, doi:10.3762/bjnano.3.72

• [4]. Recently, many studies involving charge transfer through semiconductor NPs have been performed. Photoinduced charge transfer from NPs to organic dyes [5][6] and to conductive polymers [7][8] has been reported. Light-detectors and solar cells, based on NPs, employing carbon nanotubes [9], GaAs

Nanostructures for sensors, electronics, energy and environment

• Nunzio Motta

Beilstein J. Nanotechnol. 2012, 3, 351–352, doi:10.3762/bjnano.3.40

• conditions for a widespread deployment of this technology. Their often-criticized scarce efficiency is rapidly growing, thanks to the discovery of new dyes and polymers, which are the fruit of teamwork between chemists, physicists and engineers, all working at the nanoscale. Cheap sensors based on

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

Room temperature excitation spectroscopy of single quantum dots

• Christian Blum,
• Frank Schleifenbaum,
• Martijn Stopel,
• Sébastien Peter,
• Marcus Sackrow,
• Vinod Subramaniam and
• Alfred J. Meixner

Beilstein J. Nanotechnol. 2011, 2, 516–524, doi:10.3762/bjnano.2.56

• investigations of quantum dots, we expect single molecule excitation spectroscopy to become a valuable addition to the established single molecule spectroscopy methods. The approach will not only aid in the analysis of isolated dyes or nanoparticles but also prove valuable in analyzing complex emitting systems

Platinum nanoparticles from size adjusted functional colloidal particles generated by a seeded emulsion polymerization process

• Nicolas Vogel,
• Ulrich Ziener,
• Achim Manzke,
• Alfred Plettl,
• Paul Ziemann,
• Johannes Biskupek,
• Clemens K. Weiss and
• Katharina Landfester

Beilstein J. Nanotechnol. 2011, 2, 459–472, doi:10.3762/bjnano.2.50

• for excellent monodispersity and precise control of the particle size [13][14][15]. However, problems arise when the incorporation of functionalities (e.g., co-monomers, dyes, metal complexes) is required, as the different diffusion coefficients of monomer and functional molecule complicate the

Characterization of protein adsorption onto FePt nanoparticles using dual-focus fluorescence correlation spectroscopy

• Pauline Maffre,
• Karin Nienhaus,
• Faheem Amin,
• Wolfgang J. Parak and
• G. Ulrich Nienhaus

Beilstein J. Nanotechnol. 2011, 2, 374–383, doi:10.3762/bjnano.2.43

• combined by a polarizing beam splitter (Figure 4). The lasers were pulsed alternately, each with a repetition rate of 20 MHz, so that the time lag between successive pulses was 25 ns and, thus, much longer than the fluorescence lifetime of the DY-636 dyes (~0.5 ns [46]). Both lasers were coupled into a