Direct AFM-based nanoscale mapping and tomography of open-circuit voltages for photovoltaics

• Katherine Atamanuk,
• Justin Luria and
• Bryan D. Huey

Beilstein J. Nanotechnol. 2018, 9, 1802–1808, doi:10.3762/bjnano.9.171

• and ensemble photovoltaic performance. Furthermore, direct open-circuit voltage mapping is compatible with tomographic AFM, which additionally leverages gradual nanoscale milling by the AFM probe essentially for serial sectioning. The two-dimensional and three-dimensional results for CdTe solar cells

• during in situ illumination reveal local to mesoscale contributions to PV performance based on the order of magnitude variations in photovoltaic properties with distinct grains, at grain boundaries, and for sub-granular planar defects. Keywords: cadmium telluride (CdTe); photo-conductive AFM (pcAFM); PV

• performance; solar cell; tomographic AFM; Introduction Cadmium Telluride (CdTe) is an inexpensive thin-film photovoltaic with ca. 5% of the 2017 global market share for solar cells. To optimize the efficiency and reliability of these, or any electronic devices, a thorough understanding of their composition

Multimodal noncontact atomic force microscopy and Kelvin probe force microscopy investigations of organolead tribromide perovskite single crystals

• Yann Almadori,
• David Moerman,
• Jaume Llacer Martinez,
• Philippe Leclère and
• Benjamin Grévin

Beilstein J. Nanotechnol. 2018, 9, 1695–1704, doi:10.3762/bjnano.9.161

• , including a direct band gap, high absorption coefficient, large and balanced carrier mobility, high diffusion length, long carrier lifetime and high photoluminescence quantum yield. Within a few years of their discovery, these materials were successfully used to develop photovoltaic cells [2] with power

• oxides, it originates indirectly from the superposition of photovoltaic and converse piezoelectricity effects (we refer the reader to review articles [18] for a more comprehensive introduction to the field of photostrictive materials). The photostriction observed by a few teams in organolead trialides is

• most probably related to the photovoltaic effect [16][17] and strong photon–lattice coupling [16], but its exact mechanism remains to be clarified. In principle, the photostrictive response of any material can be simply probed by recording the height variation of an AFM tip as a function of the

Artifacts in time-resolved Kelvin probe force microscopy

• Sascha Sadewasser,
• Nicoleta Nicoara and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2018, 9, 1272–1281, doi:10.3762/bjnano.9.119

• simplest approach, time-dependent changes in the CPD are observed in real time in a point measurement following an excitation pulse. Sadewasser et al. [13] studied light-induced changes in a CuGaSe2 semiconductor used in photovoltaic applications. The authors measured the surface photovoltage (SPV) – the

• electrostatic force microscopy (EFM) on organic photovoltaic blends [14][15][16]. By applying a bias pulse to the atomic force microscopy (AFM) tip, Schirmeisen et al. studied the ion transport in solid electrolytes [17]. By applying bias pulses across organic field-effect transistors (OFETs) electronic

Computational exploration of two-dimensional silicon diarsenide and germanium arsenide for photovoltaic applications

• Sri Kasi Matta,
• Chunmei Zhang,
• Yalong Jiao,
• Anthony O'Mullane and
• Aijun Du

Beilstein J. Nanotechnol. 2018, 9, 1247–1253, doi:10.3762/bjnano.9.116

• suitable for photovoltaic applications, such as excellent visible light absorption, favorable exciton formation, and charge separation are equally essential for two-dimensional (2D) materials. Here, we systematically study 2D group IV–V compounds such as SiAs2 and GeAs2 with regard to their structural

• . Furthermore, band-gap tuning is also possible by application of tensile strain. Our results highlight a new family of 2D materials with great potential for solar cell applications. Keywords: density functional theory (DFT); photovoltaic applications; solar cell; two-dimensional semiconductors; Introduction

• exciton binding energies [43][44][45] are 0.25 and 0.14 eV for SiAs2 and GeAs2, respectively. Semiconductors with exciton energies in this range of a few hundred millielectronvolts are supposed to play a key role in photovoltaic applications [46]. Conclusion We have presented 2D monolayer compounds of

P3HT:PCBM blend films phase diagram on the base of variable-temperature spectroscopic ellipsometry

• Barbara Hajduk,
• Henryk Bednarski,
• Bożena Jarząbek,
• Henryk Janeczek and
• Paweł Nitschke

Beilstein J. Nanotechnol. 2018, 9, 1108–1115, doi:10.3762/bjnano.9.102

• organic semiconductor poly(3-hexylthiophene) (P3HT) and the fullerene derivative [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) are extensively studied organic materials because of their important practical applications in organic electronics, especially in organic photovoltaic devices (OPV devices) [1

Synthesis and characterization of two new TiO₂-containing benzothiazole-based imine composites for organic device applications

• Anna Różycka,
• Agnieszka Iwan,
• Krzysztof Artur Bogdanowicz,
• Michal Filapek,
• Natalia Górska,
• Damian Pociecha,
• Marek Malinowski,
• Patryk Fryń,
• Agnieszka Hreniak,
• Jakub Rysz,
• Paweł Dąbczyński and
• Monika Marzec

Beilstein J. Nanotechnol. 2018, 9, 721–739, doi:10.3762/bjnano.9.67

• organic devices such as solar cells or light emitting diodes, the air-stable organic compounds with special architecture are needed to obtain suitable values of the various important photovoltaic parameters (Voc – open circuit voltage, Jsc – short circuit current density, FF – fill factor, PCE – power

• of diamine/amine and aldehyde/dialdehyde, are an emerging class of organic materials for organic photovoltaic applications due to their inexpensive production and short purification time [18][19][20]. In the last 10 years, photovoltaic devices containing imines and polyimines with various device

• , photovoltaic and photo-electrochemical cells, and environmental photocatalysis [34][35][36][37][38][39][40][41][42][43]. The lack of systematic studies of the influence of TiO2 on the thermal, structural and electrochemical properties of imines with benzothiazole moieties was the main reason for this work. In

Optimisation of purification techniques for the preparation of large-volume aqueous solar nanoparticle inks for organic photovoltaics

• Furqan Almyahi,
• Thomas R. Andersen,
• Nathan A. Cooling,
• Natalie P. Holmes,
• Matthew J. Griffith,
• Krishna Feron,
• Xiaojing Zhou,
• Warwick J. Belcher and
• Paul C. Dastoor

Beilstein J. Nanotechnol. 2018, 9, 649–659, doi:10.3762/bjnano.9.60

• concentration on the aqueous solar nanoparticle (ASNP) inks was investigated by monitoring the surface morphology/topography of the ASNP films using atomic force microscopy (AFM) and scanning electron microscopy (SEM) and photovoltaic device performance as a function of ultrafiltration (decreasing SDS content

• which revealed that the peak efficiencies for both methods occurred for similar surface tension values of 48.1 and 48.8 mN m−1. This work demonstrates that addressing the surface tension of large-volume ASNP inks is key to the reproducible fabrication of nanoparticle photovoltaic devices. Keywords

• : aqueous nanoparticle; crossflow ultrafiltration; miniemulsion; organic photovoltaic; SDS surfactant; surface tension; Introduction Organic photovoltaics (OPV) are a promising energy technology that utilizes large-scale roll-to-roll (R2R) fabrication techniques (such as slot-die coating, flexographical

Dynamic behavior of nematic liquid crystal mixtures with quantum dots in electric fields

• Emil Petrescu,
• Cristina Cirtoaje and
• Octavian Danila

Beilstein J. Nanotechnol. 2018, 9, 399–406, doi:10.3762/bjnano.9.39

• orientation trying to align with the field. A He–Ne laser beam crossed the sample through the windows of the holder and the emergent signal was recorded with a Thor Lab photovoltaic cell. Two crossed polarizers at 45° were placed on both sides of the sample to obtain equal intensities for ordinary and

Dynamic behavior of a nematic liquid crystal with added carbon nanotubes in an electric field

• Emil Petrescu and
• Cristina Cirtoaje

Beilstein J. Nanotechnol. 2018, 9, 233–241, doi:10.3762/bjnano.9.25

• Thor Lab photovoltaic cell was used to record the emergent beam through the sample. Results and Discussion By slowly increasing the electric field applied, the Fréedericksz transition was determined both for LC and LC + SWCNTs (Figure 6). Since the theoretical evaluation considered only small deviation

Electro-optical characteristics of a liquid crystal cell with graphene electrodes

• Nune H. Hakobyan,
• Hakob L. Margaryan,
• Valeri K. Abrahamyan,
• Vladimir M. Aroutiounian,
• Arpi S. Dilanchian Gharghani,
• Amalya B. Kostanyan,
• Timothy D. Wilkinson and
• Nelson Tabirian

Beilstein J. Nanotechnol. 2017, 8, 2802–2806, doi:10.3762/bjnano.8.279

• flexibility [4]. Many studies have been conducted on the application of graphene electrodes for light-emitting devices [5][6][7], photovoltaic devices [8][9], and touch screens [10], with much promise as a replacement for ITO. However, fundamental studies on the application of graphene as transparent

PTFE-based microreactor system for the continuous synthesis of full-visible-spectrum emitting cesium lead halide perovskite nanocrystals

• Chengxi Zhang,
• Weiling Luan,
• Yuhang Yin and
• Fuqian Yang

Beilstein J. Nanotechnol. 2017, 8, 2521–2529, doi:10.3762/bjnano.8.252

• reports on the synthesis of colloidal, hybrid organic–inorganic perovskite QDs (CH3NH3PbX3, X = Cl, Br, I and their mixture thereof) and all inorganic perovskite QDs (CsPbX3, X = Cl, Br, I and their mixture thereof) [7][8][9], which likely can be used as a photosensitive layer for photovoltaic devices

Dynamic behavior of a nematic liquid crystal mixed with CoFe₂O₄ ferromagnetic nanoparticles in a magnetic field

• Emil Petrescu,
• Cristina Cirtoaje and
• Cristina Stan

Beilstein J. Nanotechnol. 2017, 8, 2467–2473, doi:10.3762/bjnano.8.246

• recorded by a ThorLab photovoltaic cell and the data are collected to get real-time plots. The Fréedericksz transition threshold was determined by slowly increasing the applied field. It was found to be 0.047 T for the pure liquid crystal and 0.062 T for the cell containing the ferroparticles. The

Changes of the absorption cross section of Si nanocrystals with temperature and distance

• Michael Greben,
• Petro Khoroshyy,
• Sebastian Gutsch,
• Daniel Hiller,
• Margit Zacharias and
• Jan Valenta

Beilstein J. Nanotechnol. 2017, 8, 2315–2323, doi:10.3762/bjnano.8.231

• silicon, which reveals all advantages of the quantum confinement effect [1], is a promising candidate for the development of a new generation of Si photovoltaic and photonic devices [2]. SiO2-embedded silicon nanocrystals (Si NCs) can be relatively easy integrated into current CMOS technology. In

Substrate and Mg doping effects in GaAs nanowires

• Perumal Kannappan,
• Nabiha Ben Sedrine,
• Jennifer P. Teixeira,
• Maria R. Soares,
• Bruno P. Falcão,
• Maria R. Correia,
• Nestor Cifuentes,
• Emilson R. Viana,
• Marcus V. B. Moreira,
• Geraldo M. Ribeiro,
• Alfredo G. de Oliveira,
• Juan C. González and
• Joaquim P. Leitão

Beilstein J. Nanotechnol. 2017, 8, 2126–2138, doi:10.3762/bjnano.8.212

• photonic circuits, and solar cells [1][2][3]. Semiconductor nanowires have been a topic of intense research in the scope of third generation photovoltaic technology, with a predicted significant reduction of cost production [4]. Group III–V semiconductor nanowires are considered very promising materials

• carriers dynamics. This is very important for the intended photovoltaic applications of these nanowires, in which the collection of charge carriers is a key issue. On average, for growth on the GaAs(111)B substrate, the temperature dependence of the PL showed the thermal activation of non-radiative de

Parylene C as a versatile dielectric material for organic field-effect transistors

• Tomasz Marszalek,
• Maciej Gazicki-Lipman and
• Jacek Ulanski

Beilstein J. Nanotechnol. 2017, 8, 1532–1545, doi:10.3762/bjnano.8.155

• utilized in a form of protective layers stabilizing organic electronic devices. It should be pointed out that the requirements for the barrier protecting an organic transistor (about 10−2 g/m2 per day) are not as restricted as those regarding an organic photovoltaic (OPV) device (10−4 g/m2 per day) or an

Spin-chemistry concepts for spintronics scientists

• Konstantin L. Ivanov,
• Alexander Wagenpfahl,
• Carsten Deibel and
• Jörg Matysik

Beilstein J. Nanotechnol. 2017, 8, 1427–1445, doi:10.3762/bjnano.8.143

• solar cells (OSCs) [27][28]. We chose this to serve as example as it closely resembles the functional principles of systems found in spin chemistry. While OSCs have significant potential to become an inexpensive, large area and flexible photovoltaic technology at lower cost than conventional

• (electron) acceptor, as the photoactive layer. These two materials are combined either as a blend (the resulting architecture is called bulk heterojunction solar cell) or as two adjacent layers, yielding a planar heterojunction solar cell. The key processes for photovoltaic energy conversion in these types

• harvested by the solar cell concept as described above. This concept allows, therefore, internal up-conversion of incident photons, thus extending the absorption range of the photovoltaic system to the little exploited near-infrared regime of the solar spectrum. Spin dynamics in radical pairs Radical pairs

Oxidative chemical vapor deposition of polyaniline thin films

• Yuriy Y. Smolin,
• Masoud Soroush and
• Kenneth K. S. Lau

Beilstein J. Nanotechnol. 2017, 8, 1266–1276, doi:10.3762/bjnano.8.128

• demonstrated PEDOT as a neutral hole-transporting polymer for enhancing solar cells efficiency and lifetime [28]. oCVD PEDOT was also used to encapsulate flexible organic photovoltaics [29] and in the fabrication of organic photovoltaic circuits on unmodified paper [30]. Likewise, our group demonstrated the

Assembly of metallic nanoparticle arrays on glass via nanoimprinting and thin-film dewetting

• Sun-Kyu Lee,
• Sori Hwang,
• Yoon-Kee Kim and
• Yong-Jun Oh

Beilstein J. Nanotechnol. 2017, 8, 1049–1055, doi:10.3762/bjnano.8.106

• surface [1][2]. Because it is a relatively simple process [3], this technique opens up numerous applications, such as high-density magnetic recording media [2][4], photovoltaic devices [5][6][7][8][9][10], photocatalysts [11] and catalysts for the fabrication of carbon nanotubes and nanowires. However

Energy-level alignment at interfaces between manganese phthalocyanine and C₆₀

• Daniel Waas,
• Florian Rückerl,
• Martin Knupfer and
• Bernd Büchner

Beilstein J. Nanotechnol. 2017, 8, 927–932, doi:10.3762/bjnano.8.94

• fullerene C60. We show that this energy-level alignment depends upon the preparation sequence, which is explained by different molecular orientations. Moreover, our results demonstrate that MnPc/C60 interfaces are hardly suited for application in organic photovoltaic devices, since the energy difference of

• phthalocyanine-based (model) devices have been realized [28][29][30][31][32][33]. In particular, organic photovoltaic cells containing, e.g., copper phthalocyanine (CuPc) can be found rather frequently in the literature [28][30][34][35][36]. There, the charge separation at interfaces between the phthalocyanine

• be estimated to about 0.8 eV. This difference is predominantly due to the rather different energy gaps in CuPc (about 2.2 eV [52]) and MnPc (1.2 eV). As a consequence, MnPc/C60 junctions are less suited for the application in organic photovoltaic devices since the energy gain associated with the

Synthesis of coaxial nanotubes of polyaniline and poly(hydroxyethyl methacrylate) by oxidative/initiated chemical vapor deposition

• Alper Balkan,
• Efe Armagan and
• Gozde Ozaydin Ince

Beilstein J. Nanotechnol. 2017, 8, 872–882, doi:10.3762/bjnano.8.89

• applications in light emitting diodes [15], photovoltaic cells [16][17], supercapacitors [18], sensors [19] and drug delivery [20]. During synthesis of these nanostructures, the use of solvents is a major drawback for homogeneity and conformal coatings, especially on high-aspect-ratio templates, due to wetting

Synthesis of graphene–transition metal oxide hybrid nanoparticles and their application in various fields

• Arpita Jana,
• Elke Scheer and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2017, 8, 688–714, doi:10.3762/bjnano.8.74

• , multicomponent NPs have been also integrated with graphene, but such examples are still very few to date [29]. In a photovoltaic cell, sunlight energy is directly converted to electricity. Graphene and graphene–NP hybrids have been investigated extensively in the field of solar cells because of their unique

• that the energy conversion efficiency of the photovoltaic devices that use TiO2 NPs critically depends on the morphology and size of the NPs [79][80]. Additionally, in TiO2–graphene hybrid systems, the morphology of TiO2 plays an important role in various applications. TiO2 anode materials have

Analysis and modification of defective surface aggregates on PCDTBT:PCBM solar cell blends using combined Kelvin probe, conductive and bimodal atomic force microscopy

• Hanaul Noh,
• Alfredo J. Diaz and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2017, 8, 579–589, doi:10.3762/bjnano.8.62

• Hanaul Noh Alfredo J. Diaz Santiago D. Solares Department of Mechanical and Aerospace Engineering, The George Washington University, Washington, DC 20052, United States of America 10.3762/bjnano.8.62 Abstract Organic photovoltaic systems comprising donor polymers and acceptor fullerene

• -to-roll mass production [2]. There have been immense improvements regarding the efficiency of photovoltaic devices [3], their lifetime [4] and their stability [5], such that recent PSCs show power conversion efficiencies (PCE) above 10% [6] and an intrinsic lifetime approaching seven years [4]. Since

Fabrication of black-gold coatings by glancing angle deposition with sputtering

• Alan Vitrey,
• Rafael Alvarez,
• Alberto Palmero,
• María Ujué González and
• José Miguel García-Martín

Beilstein J. Nanotechnol. 2017, 8, 434–439, doi:10.3762/bjnano.8.46

• ; Introduction Black-metal coatings are metallic coatings that exhibit a high absorption in a certain region of the electromagnetic spectra. They are of interest in a wide range of applications [1][2][3][4][5][6][7] such as radiative heat exchangers, solar energy absorbers, electrodes of photovoltaic cells

In-situ monitoring by Raman spectroscopy of the thermal doping of graphene and MoS₂ in O₂-controlled atmosphere

• Aurora Piazza,
• Filippo Giannazzo,
• Gianpiero Buscarino,
• Gabriele Fisichella,
• Antonino La Magna,
• Fabrizio Roccaforte,
• Marco Cannas,
• Franco Mario Gelardi and
• Simonpietro Agnello

Beilstein J. Nanotechnol. 2017, 8, 418–424, doi:10.3762/bjnano.8.44

• ]. Especially the possibility to produce van der Waals heterostructures combining Gr and MoS2, is pushing the study of this subject [1]. Indeed, the non-zero band gap, good chemical sensitivity and photo response of MoS2 pave the way for its application in optoelectronics, sensing and photovoltaic devices [22

Performance of natural-dye-sensitized solar cells by ZnO nanorod and nanowall enhanced photoelectrodes

• Saif Saadaoui,
• Mohamed Aziz Ben Youssef,
• Moufida Ben Karoui,
• Rached Gharbi,
• Emanuele Smecca,
• Vincenzina Strano,
• Salvo Mirabella,
• Alessandra Alberti and
• Rosaria A. Puglisi

Beilstein J. Nanotechnol. 2017, 8, 287–295, doi:10.3762/bjnano.8.31

• varied between 40 and 100 nm and the length from 500 to 1000 nm, depending on the growth time. The obtained NWs had a length of 850 nm. The properties of the developed ZnO NW and NR layers with different thicknesses and their effect on the photovoltaic parameters were studied. An internal coverage of the

• ; nanorods; nanowalls; natural dye; ZnO; Introduction Energy demand has increased rapidly during the last forty years to reach a growth rate of 1.8% per year [1]. To satisfy this growing need, it is necessary to find new sources of renewable energy. For instance, photovoltaic (PV) technologies offer a

• conductive layers compared to N2 or O2, which was confirmed in the photovoltaic parameters of the final cells. We also highlight the fact that the use of a TiO2 blocking layer in the structure ZnO NW/TiO2/dye increases the photovoltaic performance of the realized DSSC by enhancing the morphological and