Active and fast charge-state switching of single NV centres in diamond by in-plane Al-Schottky junctions

• Christoph Schreyvogel,
• Vladimir Polyakov,
• Sina Burk,
• Helmut Fedder,
• Andrej Denisenko,
• Felipe Fávaro de Oliveira,
• Ralf Wunderlich,
• Jan Meijer,
• Verena Zuerbig,
• Jörg Wrachtrup and
• Christoph E. Nebel

Beilstein J. Nanotechnol. 2016, 7, 1727–1735, doi:10.3762/bjnano.7.165

• conditions. For many quantum applications, near-surface NV− centres are required in order to efficiently couple out the emitted photoluminescence or to increase its sensitivity to external magnetic fields. However, one drawback is that near-surface NV centres are strongly affected by surface defects, surface

• photoluminescence of single NV centres is changed upon applying reverse bias potentials on the Al-Schottky contact indicating an active switching from the nonfluorescent NV+ state to the fluorescent state NV0 or NV− and vice versa [21]. Then we will show the latest results on the fast switching of the NV charge

• centre sheet density in of [NV] = 106–107 cm−2. We used confocal microscopy with an excitation laser of 520 nm to detect the NV centre photoluminescence in the depletion region of the Schottky junction. Distinct spectral characteristics can be used to identify the charge state: the NV+ centre does not

Multiwalled carbon nanotube hybrids as MRI contrast agents

• Nikodem Kuźnik and
• Mateusz M. Tomczyk

Beilstein J. Nanotechnol. 2016, 7, 1086–1103, doi:10.3762/bjnano.7.102

• biocompatibility and thus biodistribution which is followed, finally, by surface modifications leading to amphiphilic or specifically targeted behavior. Moreover, their magnetic, electric and photoluminescence properties can be adjusted and exploited for desired modalities. There are visions on the application of

• photoluminescence quenching. This functionalization allows for europium photoluminescence emission and endows the hybrids with a second, optical modality. We took another approach to MWCNT functionalization by introducing N-phenylaziridine groups on the carbon scaffold [26] in the reaction of aryl azide with

Photocurrent generation in carbon nanotube/cubic-phase HfO₂ nanoparticle hybrid nanocomposites

• Protima Rauwel,
• Augustinas Galeckas,
• Martin Salumaa,
• Frédérique Ducroquet and
• Erwan Rauwel

Beilstein J. Nanotechnol. 2016, 7, 1075–1085, doi:10.3762/bjnano.7.101

• 2.6 nm has been synthesized. Free standing HfO2 NPs present unusual optical properties and a strong photoluminescence emission in the visible region, originating from surface defects. Transmission electron microscopy studies show that these NPs decorate the MWCNTs on topological defect sites. The

• photoluminescence of the nanocomposites indicates features attributed to combined effects of charge desaturation of HfO2 surface states and charge transfer to the MWCNTs with an overall reduction of radiative recombination. Finally, photocurrent generation under UV–vis illumination suggests that a HfO2 NP/MWCNT

• dimensionality of nanoparticles; among established methods ensuring control of both size and shape is the nonaqueous sol–gel route [18][19]. In our previous studies, a strong photoluminescence in the visible range was observed from HfO2 nanoparticles under below-bandgap excitation [20][21] and attributed to

The influence of phthalocyanine aggregation in complexes with CdSe/ZnS quantum dots on the photophysical properties of the complexes

• Irina V. Martynenko,
• Anna O. Orlova,
• Vladimir G. Maslov,
• Anatoly V. Fedorov,
• Kevin Berwick and
• Alexander V. Baranov

Beilstein J. Nanotechnol. 2016, 7, 1018–1027, doi:10.3762/bjnano.7.94

• energy donor in QD/tetrapyrrole complexes because of their unique optical properties. QDs exhibit an extremely high extinction over a broad spectral range and a high quantum yield (QY) of photoluminescence (PL) [12][13][14]. In addition, the emission properties of QDs can be tuned through the size of the

• molecules in complexes may be the reason for the decrease of the tetrapyrrole photoluminescence intensity in complexes and this may explain the observed concentration dependence of photophysical properties of the complexes. It is well-known that the aggregation of acceptor molecules can dramatically reduce

• formation increases with increasing relative molecule concentration n in the mixture, resulting in a concentration dependence of the photophysical properties of the complexes. QDs are energy donors and molecules are energy acceptors during energy transfer within complexes. QD photoluminescence is completely

Phenalenyl-based mononuclear dysprosium complexes

• Yanhua Lan,
• Andrea Magri,
• Olaf Fuhr and
• Mario Ruben

Beilstein J. Nanotechnol. 2016, 7, 995–1009, doi:10.3762/bjnano.7.92

• , aimed to study gas-phase dispersed photoluminescence spectra [25][26]. In this paper we report on the synthesis of three mononuclear dysprosium complexes [Dy(PLN)2(HPLN)Cl(EtOH)] (1), [Dy(PLN)3(HPLN)]·[Dy(PLN)3(EtOH)]·2EtOH (2) and [Dy(PLN)3(H2O)2]·H2O (3) with the focus on studying their magnetic

• the effect of the structure on the photoluminescence of those complexes. Magnetic studies Both static (dc) and dynamic (ac) magnetic properties have been investigated of the complexes 1–3, but not for 4. The single crystal structure of complex 4 is not available up to now and the sublimed product 4

Optical absorption signature of a self-assembled dye monolayer on graphene

• Tessnim Sghaier,
• Sylvain Le Liepvre,
• Céline Fiorini,
• Ludovic Douillard and
• Fabrice Charra

Beilstein J. Nanotechnol. 2016, 7, 862–868, doi:10.3762/bjnano.7.78

• -3,4,9,10-tetracarboxylic dianhydride (PTCDA), have become archetypes for photonic applications of dyes [12], for self-organized adsorption on various atomically flat surfaces [13], and for their combination. Indeed, optical differential reflectance spectroscopy [14], photoluminescence, or Raman diffraction

Assembling semiconducting molecules by covalent attachment to a lamellar crystalline polymer substrate

• Rainhard Machatschek,
• Patrick Ortmann,
• Renate Reiter,
• Stefan Mecking and
• Günter Reiter

Beilstein J. Nanotechnol. 2016, 7, 784–798, doi:10.3762/bjnano.7.70

Facile synthesis of water-soluble carbon nano-onions under alkaline conditions

• Gaber Hashem Gaber Ahmed,
• Rosana Badía Laíño,
• Josefa Angela García Calzón and
• Marta Elena Díaz García

Beilstein J. Nanotechnol. 2016, 7, 758–766, doi:10.3762/bjnano.7.67

• leaves (acer saccharum), under the same temperature and alkaline conditions did not produce carbon onions. XRD, FTIR, HRTEM, UV–vis spectroscopy, and photoluminescence analyses were performed to characterize the as-synthesized carbon nanomaterials. Preliminary tests demonstrate a capability of the

• versatile materials for chemical sensing of metal ions. The high content of lycopene in tomatoes may explain the formation of C-onions in alkaline media and a possible formation mechanism for such structures was outlined. Keywords: carbon dots; carbon onions; metal-ion sensing; photoluminescence; thermal

• discovered before the former [1]. C-dots are a special class of carbon nanoparticles that have interesting practical advantages such as low toxicity, relatively small size (≤10 nm), chemical stability, high solubility in water and easy synthesis. Besides, owing to their remarkable photoluminescence (PL

Bacteriorhodopsin–ZnO hybrid as a potential sensing element for low-temperature detection of ethanol vapour

• Saurav Kumar,
• Sudeshna Bagchi,
• Senthil Prasad,
• Anupma Sharma,
• Ritesh Kumar,
• Rishemjit Kaur,
• Jagvir Singh and
• Amol P. Bhondekar

Beilstein J. Nanotechnol. 2016, 7, 501–510, doi:10.3762/bjnano.7.44

• nonhybrid structures, as is evident from Figure 2c,d. The structural and optical properties of ZnO-TF, ZnO-NR and their hybrid structures were assessed using UV–vis spectroscopy, photoluminescence spectroscopy (PL), Raman spectroscopy and Fourier transform infrared spectroscopy (FTIR). Figure 3 shows the

• spectrophotometer (Hitachi, 3900 H). The photoluminescence (PL) spectrum was measured using a Varian spectrofluorometer. The Raman spectra were taken using a 514 nm wavelength laser source with a Renishaw Invia spectrophotometer. A Perkin Elmer spectrophotometer was used for the FTIR analysis of the samples. The

• ). Photoluminescence spectral analysis for the ITO/ZnO-TF and ITO/ZnO-NR structures, and the respective hybrid structure for the structural analysis of the surface. Raman spectra. (a) ZnO-TF shows the characteristic peaks for ZnO at 467 cm−1, 563 cm−1 and 800 cm−1; (b) ZnO-TF/bR hybrid structure showing characteristic

Linear and nonlinear optical properties of hybrid metallic–dielectric plasmonic nanoantennas

• Mario Hentschel,
• Bernd Metzger,
• Bastian Knabe,
• Karsten Buse and
• Harald Giessen

Beilstein J. Nanotechnol. 2016, 7, 111–120, doi:10.3762/bjnano.7.13

• ][49]. If one indeed aims at mapping the near-field, one can make use of two-photon photoluminescence [50][51], multiphoton absorption [52], selectively placed molecules for SEIRA [53], or by directly measuring them by scattering and scanning type near-field optical microscopy [54][55][56]. In these

Dependence of lattice strain relaxation, absorbance, and sheet resistance on thickness in textured ZnO@B transparent conductive oxide for thin-film solar cell applications

• Kuang-Yang Kou,
• Yu-En Huang,
• Chien-Hsun Chen and
• Shih-Wei Feng

Beilstein J. Nanotechnol. 2016, 7, 75–80, doi:10.3762/bjnano.7.9

• microcrystallites has a strong green emission due to defect states in the core [11]. A blue-shifted absorption edge and photoluminescence caused by quantum confinement as well as a higher photovoltaic and sensor performance due to a larger surface area have been demonstrated in ZnO nanocrystals [14][15][16]. In

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

• molecular scale (Hal = I, Br, Cl). We report about the synthesis of the precursors, their transformation into halogene-containing ZnO materials, and finally structural, optical and electronic properties are investigated using a combination of techniques including FT-Raman, low-T photoluminescence, impedance

• photoluminescence measurements were performed using a Horiba Jobin Yvon T64000 setup with a nitrogen-cooled CCD. Low-temperature photoluminescence measurements were conducted using an Oxford micro-cryostat with a temperature range from 4 to 350 K. The samples were excited by the 350 nm line of a krypton ion laser

• incorporation leads to strain. However, this is not in agreement with PXRD data, FT-Raman data (see below) and low-T photoluminescence measurements. Therefore, it seems that the enlargement of Egap is due to electronic reasons. For semiconductors with high doping and a significant concentration of free charge

Mapping bound plasmon propagation on a nanoscale stripe waveguide using quantum dots: influence of spacer layer thickness

• Chamanei S. Perera,
• Alison M. Funston,
• Han-Hao Cheng and
• Kristy C. Vernon

Beilstein J. Nanotechnol. 2015, 6, 2046–2051, doi:10.3762/bjnano.6.208

• incoupling to the desired mode. A homogeneous thin layer of quantum dots was used to image the near field intensity of the propagating plasmons on the waveguide. We observed that the photoluminescence is quenched when the QD to metal surface distance is less than 10 nm. The optimised spacer layer thickness

• for the stripe waveguides was found to be around 20 nm. Authors believe that the findings of this paper prove beneficial for the development of plasmonic devices utilising stripe waveguides. Keywords: photoluminescence; plasmonics; quantum dot; spacer layer; stripe waveguide; Introduction Plasmons

• [1][7]. Photoluminescence of the QD occurs due to excitation of the QD by the incident field of the propagating SPP on the stripe. Intensity of the QD photoluminescence (PL) arising from the propagating plasmons is proportional to the intensity of the local electric field at the given position [7][8

A facile method for the preparation of bifunctional Mn:ZnS/ZnS/Fe₃O₄ magnetic and fluorescent nanocrystals

• Houcine Labiadh,
• Tahar Ben Chaabane,
• Romain Sibille,
• Lavinia Balan and
• Raphaël Schneider

Beilstein J. Nanotechnol. 2015, 6, 1743–1751, doi:10.3762/bjnano.6.178

• heterostructures were characterized by X-ray diffraction (XRD), dynamic light scattering (DLS), transmission electron microscopy (TEM), UV–vis spectroscopy and photoluminescence (PL) spectroscopy. The PL spectra of Mn:ZnS/ZnS/Fe3O4 quantum dots (QDs) showed marked visible emission around 584 nm related to the 4T1

• , QDs possess many advantages, including a broad absorption with a narrow photoluminescence (PL) spectra, low photobleaching, high PL quantum yield (QY), tunable emission from the visible to infrared wavelengths, and high resistance to chemical degradation [3][4]. Such characteristics originate from

• by sonication and transferred to quartz cuvettes using a syringe. The absorption spectra were recorded on a Thermo Scientific, Evolution 220 UV–vis spectrophotometer. The photoluminescence spectra were recorded on a Horiba, Fluoromax-4, Jobin Yvon spectrofluorimeter. The QY values were determined

Addition of Zn during the phosphine-based synthesis of indium phospide quantum dots: doping and surface passivation

• Natalia E. Mordvinova,
• Alexander A. Vinokurov,
• Oleg I. Lebedev,
• Tatiana A. Kuznetsova and
• Sergey G. Dorofeev

Beilstein J. Nanotechnol. 2015, 6, 1237–1246, doi:10.3762/bjnano.6.127

• used as standard for the determination of the photoluminescence quantum yields (QY). Right after synthesis hexane was added to the reaction mixture and a white precipitate was removed through centrifugation. According to XRF spectroscopy, this precipitate consists almost of zinc myristate. To purify

• room temperature with a Varian Cary 50 spectrophotometer in a 1 cm quartz cuvette from 200 to 1100 nm. Photoluminescence (PL) spectra were measured in the same cuvette at room temperature with an Ocean Optics 4000 USB spectrometer calibrated by using a 2600 K W-lamp. Excitation of PL was carried out by

Electronic interaction in composites of a conjugated polymer and carbon nanotubes: first-principles calculation and photophysical approaches

• Florian Massuyeau,
• Jany Wéry,
• Jean-Luc Duvail,
• Serge Lefrant,
• Abu Yaya,
• Chris Ewels and
• Eric Faulques

Beilstein J. Nanotechnol. 2015, 6, 1138–1144, doi:10.3762/bjnano.6.115

• photoexcitation techniques and density functional theory. Charge separation is confirmed experimentally by rapid quenching of PPV photoluminescence and changes in photocurrent starting at relatively low concentrations of SWNT. Calculations predict strong electronic interaction between the polymer and the SWNT

• network when nanotubes are semiconducting. Keywords: composite; conjugated polymer; DFT calculations; energy transfer; photoconductivity; single wall carbon nanotubes; time-resolved photoluminescence; Introduction Electroactive conjugated polymers (ECPs) are technologically promising for organic light

• green-yellow range, and photoconduction under UV or blue light excitation. In this report we present an investigation of the photoexcitation and exciton migration processes in composites of PPV and single-walled carbon nanotubes (SWNT) by means of time-resolved photoluminescence (PL) and

Charge carrier mobility and electronic properties of Al(Op)₃: impact of excimer formation

• Andrea Magri,
• Pascal Friederich,
• Bernhard Schäfer,
• Valeria Fattori,
• Xiangnan Sun,
• Timo Strunk,
• Velimir Meded,
• Luis E. Hueso,
• Wolfgang Wenzel and
• Mario Ruben

Beilstein J. Nanotechnol. 2015, 6, 1107–1115, doi:10.3762/bjnano.6.112

• )3 are reported. Phenalenyl-based complexes (more specifically lanthanoid phenalenyls) have been previously studied for their peculiar photoluminescence in the gas phase [18][19]. Greisch et al. observed that the alkali metal cationization of Eu(Op)3 increases the capability of the ligand 1-oxo-1H

• photophysical properties in solution and in thin film are summarized in Table 1 and are consistent with excimer formation. In more detail, Al(Op)3 in solution is characterized by a photoluminescence quantum yield (Φ) of 0.027 and a lifetime (τ) of 0.7 ns. In the form of a thin film, the quantum yield (Φ) is

• -based simulations (1.4 × 10−4 cm2·V−1·s−1 electron mobility and 9.5 × 10−6 cm2·V−1·s−1 hole mobility) indicated that the material would be a good Alq3 alternative. However, excimer formation, as observed in the photoluminescence experiments in the solid state, may play the most decisive role in

Superluminescence from an optically pumped molecular tunneling junction by injection of plasmon induced hot electrons

• Kai Braun,
• Xiao Wang,
• Andreas M. Kern,
• Hilmar Adler,
• Heiko Peisert,
• Thomas Chassé,
• Dai Zhang and
• Alfred J. Meixner

Beilstein J. Nanotechnol. 2015, 6, 1100–1106, doi:10.3762/bjnano.6.111

• the amplified photoluminescence (PL) emission back towards the metal/molecule/metal junction in resonance to the gap mode where the intensity reaches a maximum, i.e., in the spectral region of the most intense Raman lines. Indeed resonant surface plasmon amplification by stimulated emission from

Characterization of nanostructured ZnO thin films deposited through vacuum evaporation

• Jose Alberto Alvarado,
• Arturo Maldonado,
• Héctor Juarez,
• Mauricio Pacio and
• Rene Perez

Beilstein J. Nanotechnol. 2015, 6, 971–975, doi:10.3762/bjnano.6.100

• different sizes in the nanostructure. Film thicknesses between 45 nm and 123 nm were measured through profilometry after deposition times of 5, 10, 15, 20, and 25 min. Photoluminescence characteristics of thin films The ZnO thin films annealed at 25, 400 and 600°C were analyzed by PL shown in Figure 5

• 45 nm and 123 nm by varying the deposition time (5 to 25 min). The XRD results show that this is a polycrystalline nanostructured thin film, and this is confirmed with the HRSEM images, but it is formed only at 600°C and disappears as the annealing temperature increases. From the photoluminescence we

Observing the morphology of single-layered embedded silicon nanocrystals by using temperature-stable TEM membranes

• Sebastian Gutsch,
• Daniel Hiller,
• Jan Laube,
• Margit Zacharias and
• Christian Kübel

Beilstein J. Nanotechnol. 2015, 6, 964–970, doi:10.3762/bjnano.6.99

• interface defects and hence leads to higher photoluminescence intensities as compared to Ar annealing [40][41]. Therefore, 10 nm SiO0.93 films were annealed in Ar and N2 (samples S4 and S5) atmosphere and compared by plane-view EFTEM that is presented in Figure 3. As can be seen at lower magnification

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

• 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

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

• of the films was evaluated by high-resolution XRD system (PAnalyticalX’pert, PRO MRD PW3040, Netherlands) with a Cu Kα radiation source of λ = 1.5406 Å. For the high-resolution measurements, this system resolution was 12 arc/s. An integrated micro-photoluminescence and a Raman spectrometer (Jobin

Silica micro/nanospheres for theranostics: from bimodal MRI and fluorescent imaging probes to cancer therapy

• Shanka Walia and
• Amitabha Acharya

Beilstein J. Nanotechnol. 2015, 6, 546–558, doi:10.3762/bjnano.6.57

• measured by using a super conducting quantum interface device (SQUID) magnetometer. The photoluminescence spectra of silica coated Gd2(CO3)3:Tb NPs showed a characteristic charge-transfer band at 225 nm and a narrow peak at 274 nm. The T1-weighted MR images were obtained by using a 0.5 T magnet. The

• antimouse IgG (GM IgG). The characterization of the prepared nanocomposites was performed through TEM, UV–vis and photoluminescence (PL) spectrometry and fluorescence microscopy studies. The absorption peak for CdTe QDs was observed at 570 nm and was shifted to 540 nm after silica coating of NPs. This shift

• TEOS and finally amine functionalization was achieved by using APS. At last MPA-activated CdTe QDs were incorporated into a silica shell containing Fe3O4 NPs. The synthesized NPs were characterized by XRD, TEM, photoluminescence spectroscopy and magnetometry studies. In powder XRD, six diffraction

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

• field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), BET surface area, UV–vis diffuse reflectance spectra (UV-DRS), Raman and photoluminescence (PL) analyses. The simple and smart synthesis anchored well the deposition

• NPs can be distinguished by two peaks centered at binding energies of 334.3 eV and 340.0 eV, which are assigned to Pd 3d5/2, and Pd 3d3/2, respectively (Figure 6b) [48] and confirm the predominantly metallic form of the deposited noble metal. Optical absorption and photoluminescence The optical

• % and 3.0 wt %) on the photocatalytic efficiency showed an optimum value at 0.5 wt %. According to the optical spectra and photoluminescence analysis the 1.0 wt % Pd/TiO2 was expected to yield a better photocatalytic efficiency than the others. This unexpected observance can be attributed to the

Carrier multiplication in silicon nanocrystals: ab initio results

• Ivan Marri,
• Marco Govoni and
• Stefano Ossicini

Beilstein J. Nanotechnol. 2015, 6, 343–352, doi:10.3762/bjnano.6.33

• Trinh et al. [36] in order to explain results obtained in photoluminescence (PL) and induced absorption (IA) experiments conducted on dense arrays of silicon nanocrystals (Si-NCs, NC–NC separation ≤ 1 nm). In the first set of experiments, the authors proved that although the excitation cross-section is