Ellipsometry and XPS comparative studies of thermal and plasma enhanced atomic layer deposited Al₂O₃-films

• Jörg Haeberle,
• Karsten Henkel,
• Hassan Gargouri,
• Franziska Naumann,
• Bernd Gruska,
• Michael Arens,
• Massimo Tallarida and
• Dieter Schmeißer

Beilstein J. Nanotechnol. 2013, 4, 732–742, doi:10.3762/bjnano.4.83

• been investigated for several applications like surface passivation or encapsulation in organic and inorganic photovoltaic devices [1][2], interfacial buffering for high-k dielectrics [3][4], organic memories [5], and nano-laminates [6] as well as work function modification [7], gas diffusion barrier

Surface passivation and optical characterization of Al₂O₃/a-SiC_x stacks on c-Si substrates

• Gema López,
• Pablo R. Ortega,
• Cristóbal Voz,
• Isidro Martín,
• Mónica Colina,
• Anna B. Morales,
• Albert Orpella and
• Ramón Alcubilla

Beilstein J. Nanotechnol. 2013, 4, 726–731, doi:10.3762/bjnano.4.82

• experimentally determined the optimum thickness of the stack for photovoltaic applications by minimizing the reflection losses over a wide wavelength range (300–1200 nm) without compromising the outstanding passivation properties of the Al2O3 films. The upper limit of the surface recombination velocity (Seff,max

• ; silicon carbide (SiCx); surface passivation; Introduction Surface passivation has become a relevant issue in high efficiency crystalline silicon (c-Si) solar cells. The importance is even increasing as thinner wafers are used to reduce the cost for photovoltaic applications [1]. Aluminum oxide (Al2O3

• . Therefore, absorption of light by the Al2O3 layer does not occur in the wavelength range relevant for photovoltaic applications. For the sake of clarity, only the 300 to 600 nm wavelength range is depicted, i.e, in which a relevant absorbance can exist. However, it can be seen that as the a-SiCx layer

Evolution of microstructure and related optical properties of ZnO grown by atomic layer deposition

• Adib Abou Chaaya,
• Roman Viter,
• Mikhael Bechelany,
• Zanda Alute,
• Donats Erts,
• Anastasiya Zalesskaya,
• Kristaps Kovalevskis,
• Vincent Rouessac,
• Valentyn Smyntyna and
• Philippe Miele

Beilstein J. Nanotechnol. 2013, 4, 690–698, doi:10.3762/bjnano.4.78

• temperature caused by quantum confinement [11] and, an improvement of the photovoltaic and sensor performance due to a high surface area [12][13]. ZnO nanostructures are obtained as nanoparticles [14], nanotubes [15], nanowires [5][7], and ultrathin films [16][17]. Ultrathin ZnO films can be synthesized by

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

• conversion efficiencies up to 3.0% and external quantum efficiencies up to 40% were obtained through the use of 1-chloronaphthalene as solvent additive in the fabrication of the photovoltaic devices. Furthermore, atomic force microscopy investigations of the photoactive layer gave insight into the

• devices typically display much better performances in photovoltaic cells. Keywords: active layer morphology; comparison vacuum-processed solar cells; maximum solubility; oligothiophene; solar cells; solution-processed bulk heterojunction; solvent additives; Introduction The demand for the development of

• as its solubility, this material has the unique advantage of being processable in both vacuum and solution. This allows for a direct comparison of the two deposition techniques and the resulting solar cell performances. There have been several reports describing the photovoltaic characteristics of

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

• University, Ramat-Aviv 69978, Israel Department of Chemistry, University of Basel, Spitalstrasse 51 CH4056, Switzerland 10.3762/bjnano.4.49 Abstract Dye-sensitized solar cells (DSCs) provide a promising third-generation photovoltaic concept based on the spectral sensitization of a wide-bandgap metal oxide

• ); surface photovoltage (SPV); titanium dioxide (TiO2); Introduction Dye-sensitized solar cells (DSCs) provide a promising low-cost, high-efficiency third-generation photovoltaic concept based on the spectral sensitization of a nanoporous wide bandgap semiconductor [1][2]. In the past two decades DSCs have

• ., surface topography and potential, are still unclear and have the potential to increase the efficiency and long-term stability of the devices. Investigations of nanoscaled photovoltaic devices require nanometer-scale measuring methods, including time-resolved measurements of the carrier dynamics [15][16

High-resolution electrical and chemical characterization of nm-scale organic and inorganic devices

• Pierre Eyben

Beilstein J. Nanotechnol. 2013, 4, 318–319, doi:10.3762/bjnano.4.35

• increase in “More than Moore” developments targeting energy (photovoltaic, energy storage), imaging (e.g., quantitative medical imaging), sensor/actuators linked to CMOS-base circuitry, biochips, etc. The utilization of graphene in order to process high mobility (both for holes and electrons) field-effect

• , electrochromic devices, biosensors, photodiodes, photovoltaic cells, etc.) have been developed, demonstrating the strong potential of these materials. However, the advent of commercial applications often requires important breakthroughs towards more efficient and stable organic photovoltaic devices. This implies

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

• Ulrich Herr,
• Balati Kuerbanjiang,
• 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

• [1]. Nanotechnology holds great promises for the development of new devices in the field of advanced energy conversion. This became very apparent with the development of the dye-sensitized solar cells by M. Grätzel [2] more than 20 years ago. Other than conventional semiconductor photovoltaic cells

• modified by the presence of plasmonic metal structures, but also the transfer of charges (typically in the form of electrons and holes), which may support either an external flow of charge in the electrical circuit connected to the photovoltaic cell, or a chemical reaction in which the energy carrier is

Functionalization of vertically aligned carbon nanotubes

• Eloise Van Hooijdonk,
• Carla Bittencourt,
• Rony Snyders and
• Jean-François Colomer

Beilstein J. Nanotechnol. 2013, 4, 129–152, doi:10.3762/bjnano.4.14

• products showed a high-quality structural arrangement and an enhanced electrical conductivity. Many physical properties such as morphology, thermal stability, conductivity and charge carrier mobility are disrupted by this treatment. This can be crucial for applications in the photovoltaic field. We can

Characterization and properties of micro- and nanowires of controlled size, composition, and geometry fabricated by electrodeposition and ion-track technology

• Maria Eugenia Toimil-Molares

Beilstein J. Nanotechnol. 2012, 3, 860–883, doi:10.3762/bjnano.3.97

• photovoltaic applications. CdTe and CdS rods are mostly synthesized by chemical vapour deposition, and sol–gel processes. Electrodeposition of stoichiometric CdTe nanowires with diameters between 80 nm and 1 μm was reported by Enculescu et al. [95]. In addition to SEM, TEM, EDX, and XRD characterization, they

• available surface, and thus can be an important advantage, e.g., for catalytic and photovoltaic applications. We have been able to tune the surface roughness of the electrodeposited nanowires by selecting suitable polymer membranes: etched tracks in PC result in smooth channel walls, while channels in PET

• and conical geometry are promising electrodes for field emission, photovoltaic applications, water splitting, or surface-enhanced Raman spectroscopy [112][113]. The individual cones potentially combine the advantages offered by the reduced dimensions of the tip with the enhanced mechanical stability

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

• . Keywords: charge transfer; energy transfer; nanoparticles; organic linker; quantum dots; Introduction Self-assembled structures of semiconductor nanoparticles (NPs) are viewed as a possible avenue for producing photovoltaic devices with efficient collection of light and charge separation processes [1

Polymer blend lithography: A versatile method to fabricate nanopatterned self-assembled monolayers

• Cheng Huang,
• Markus Moosmann,
• Jiehong Jin,
• Tobias Heiler,
• Stefan Walheim and
• Thomas Schimmel

Beilstein J. Nanotechnol. 2012, 3, 620–628, doi:10.3762/bjnano.3.71

• intensively studied over the past two decades and allows the formation of complex layered or lateral micro- or nanoscale structures [31][32][33][34][35][36][37][38]. These structures can be used for many applications, such as antireflection coatings [39], photovoltaic devices [40][41], organic light-emitting

Reduced electron recombination of dye-sensitized solar cells based on TiO₂ spheres consisting of ultrathin nanosheets with [001] facet exposed

• Hongxia Wang,
• Meinan Liu,
• Cheng Yan and
• John Bell

Beilstein J. Nanotechnol. 2012, 3, 378–387, doi:10.3762/bjnano.3.44

• ; ultrathin nanosheets; Introduction In the past two decades, dye-sensitized solar cells (DSCs) have received substantial attention from both academic and industrial communities as one of the most promising low-cost, high-efficiency third-generation photovoltaic devices [1][2]. A typical DSC consists of a

• structure consisting of ultrathin nanosheets with 100% of the [001] facet exposed were synthesized and applied in dye-sensitized solar cells (DSCs). The photovoltaic performance of the DSCs with different concentrations of the hierarchically structured TiO2 spheres was evaluated. The kinetics of electron

Structural, electronic and photovoltaic characterization of multiwalled carbon nanotubes grown directly on stainless steel

• Luca Camilli,
• Manuela Scarselli,
• Silvano Del Gobbo,
• Paola Castrucci,
• Eric Gautron and
• Maurizio De Crescenzi

Beilstein J. Nanotechnol. 2012, 3, 360–367, doi:10.3762/bjnano.3.42

• silicon substrate plays an important role in the production of electron–hole pairs. Keywords: carbon nanotubes; electronic properties; heterojunction; photovoltaic; stainless steel; Introduction Carbon nanotubes (CNTs) possess unique electronic, mechanical and optical properties that make them

• of graphite. In particular, a broadening of the π-plasmon of CNTs is found, which can be ascribed to the presence of several structures that are completely absent in HOPG and probably due to transitions among Van Hove singularities. Here we also show that MWCNTs exhibit an interesting photovoltaic

• activity when they are deposited on a crystalline silicon substrate by the airbrush method. We recall that, while several efforts have been devoted to the build-up of photovoltaic devices based on a SWCNT–Si heterojunction, achieving a surprising efficiency of up to 11% [8], just a few works reported the

Junction formation of Cu₃BiS₃ investigated by Kelvin probe force microscopy and surface photovoltage measurements

• Fredy Mesa,
• William Chamorro,
• William Vallejo,
• Robert Baier,
• Thomas Dittrich,
• Alexander Grimm,
• Martha C. Lux-Steiner and
• Sascha Sadewasser

Beilstein J. Nanotechnol. 2012, 3, 277–284, doi:10.3762/bjnano.3.31

• 10.3762/bjnano.3.31 Abstract Recently, the compound semiconductor Cu3BiS3 has been demonstrated to have a band gap of ~1.4 eV, well suited for photovoltaic energy harvesting. The preparation of polycrystalline thin films was successfully realized and now the junction formation to the n-type window needs

• the influence of defect states below the band gap on charge separation and a surface-defect passivation by the In2S3 buffer layer. Our findings indicate that Cu3BiS3 may become an interesting absorber material for thin-film solar cells; however, for photovoltaic application the band bending at the

• photovoltaic active interface with a SPV of ~130 mV [7]. It is well known from the Cu(In,Ga)Se2 solar cells that a buffer layer is required between the n-ZnO window and the p-type absorber layer to reach high efficiency values [8]. Traditionally, CdS deposited by chemical bath deposition (CBD) has been used as

Surface functionalization of aluminosilicate nanotubes with organic molecules

• Wei Ma,
• Weng On Yah,
• Hideyuki Otsuka and
• Atsushi Takahara

Beilstein J. Nanotechnol. 2012, 3, 82–100, doi:10.3762/bjnano.3.10

• . Therefore, it is crucial to develop a facile synthetic method capable of making uniform and template-free imogolite/P3HT nanofiber hybrids in bulk quantities. Such a synthetic method would be useful for tuning the properties of sensors and photovoltaic or light-emitting devices, which are dependent on well

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

Highly efficient ZnO/Au Schottky barrier dye-sensitized solar cells: Role of gold nanoparticles on the charge-transfer process

• Tanujjal Bora,
• Htet H. Kyaw,
• Soumik Sarkar,
• Samir K. Pal and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2011, 2, 681–690, doi:10.3762/bjnano.2.73

• shown in Figure 2b. The solar cells with ZnO-nanorod and ZnO/Au-nanocomposite photoelectrodes in the absence of dye N719 were initially prepared in order to study the photovoltaic behavior of the ZnO/Au-nanocomposite system. The J–V characteristics of these solar cells are shown in Table 1. Upon

Nanophotonics, nano-optics and nanospectroscopy

• Alfred J. Meixner

Beilstein J. Nanotechnol. 2011, 2, 499–500, doi:10.3762/bjnano.2.53

• applications can be imagined, e.g., in materials sciences in the pursuit of efficient photovoltaic energy conversion; in the engineering sciences as quantum devices functioning as switches that truly operate at the quantum limit with single photons; or in the life sciences as local optical sensors to observe

Formation of precise 2D Au particle arrays via thermally induced dewetting on pre-patterned substrates

• Dong Wang,
• Ran Ji and
• Peter Schaaf

Beilstein J. Nanotechnol. 2011, 2, 318–326, doi:10.3762/bjnano.2.37

• applicability of this method in fabricating large areas of particle arrays for the plasmonic devices or in improving the efficiency of the photovoltaic devices and light-emitting diodes (LED) by modification of the surface optical properties. Experimental The surface of (100) Si wafers was pre-patterned into a

Room temperature synthesis of indium tin oxide nanotubes with high precision wall thickness by electroless deposition

• Mario Boehme,
• Emanuel Ionescu,
• Ganhua Fu and
• Wolfgang Ensinger

Beilstein J. Nanotechnol. 2011, 2, 119–126, doi:10.3762/bjnano.2.14

• of the polycarbonate template having a tube density from 1 to 109 tubes/cm². These arrays can be used directly for sensor, photovoltaic or electronic applications. Experimental Sample preparation Polycarbonate foils with thicknesses of 6 to 30 µm were used as templates. Commercial polycarbonate (PC