Magnetic properties of biofunctionalized iron oxide nanoparticles as magnetic resonance imaging contrast agents

• Natalia E. Gervits,
• Andrey A. Gippius,
• Alexey V. Tkachev,
• Evgeniy I. Demikhov,
• Sergey S. Starchikov,
• Igor S. Lyubutin,
• Alexander L. Vasiliev,
• Vladimir P. Chekhonin,
• Maxim A. Abakumov,
• Alevtina S. Semkina and
• Alexander G. Mazhuga

Beilstein J. Nanotechnol. 2019, 10, 1964–1972, doi:10.3762/bjnano.10.193

• temperature range of 10–300 K with a standard MS-1104Em spectrometer operated in the constant acceleration regime [30][31]. The gamma ray source 57Co(Rh) was maintained at room temperature. The calibration was performed with a metal α-Fe standard absorber. The XRD patterns were collected using the Rigaku

TiO₂/GO-coated functional separator to suppress polysulfide migration in lithium–sulfur batteries

• Ning Liu,
• Lu Wang,
• Taizhe Tan,
• Yan Zhao and
• Yongguang Zhang

Beilstein J. Nanotechnol. 2019, 10, 1726–1736, doi:10.3762/bjnano.10.168

• /GO-coated separator was introduced between the Li anode and sulfur cathode as a highly efficient polysulfide absorber. The TiO2/GO composite was prepared by dealloying, as reported elsewhere [35], and subsequent spray drying. It has been demonstrated that the utilization of the TiO2/GO composite

CuInSe₂ quantum dots grown by molecular beam epitaxy on amorphous SiO₂ surfaces

• Henrique Limborço,
• Pedro M.P. Salomé,
• Rodrigo Ribeiro-Andrade,
• Jennifer P. Teixeira,
• Nicoleta Nicoara,
• Kamal Abderrafi,
• Joaquim P. Leitão,
• Juan C. Gonzalez and
• Sascha Sadewasser

Beilstein J. Nanotechnol. 2019, 10, 1103–1111, doi:10.3762/bjnano.10.110

• with the average size of the nanodots. Keywords: copper indium gallium selenide (CuInSe2); quantum dots; Introduction The chalcopyrite compound Cu(In,Ga)Se2 (CIGS) is used as the light absorber layer in thin film solar cells that typically consist of a glass substrate, a Mo back contact, the CIGS

Fe₃O₄ nanoparticles as a saturable absorber for giant chirped pulse generation

• Ji-Shu Liu,
• Xiao-Hui Li,
• Abdul Qyyum,
• Yi-Xuan Guo,
• Tong Chai,
• Hua Xu and
• Jie Jiang

Beilstein J. Nanotechnol. 2019, 10, 1065–1072, doi:10.3762/bjnano.10.107

• communication. Here, we report the use of FONPs synthesized by a sol–hydrothermal method and used as a saturable absorber (SA) to achieve nanosecond pulses in an erbium-doped fiber laser (EDFL) for the first time. The proposed fiber laser is demonstrated to have a narrow spectral width of around 0.8 nm and a

• , and optical modulators. Keywords: erbium laser; Fe3O4 nanoparticles; fiber lasers; saturable absorber; Introduction Fe3O4 nanoparticles (FONPs) are excellent magnetic materials, which allows for many applications in various fields such as medical transmission, microwave devices, and optical devices

• absorption band does not increase because most of the FONPs have a non-stoichiometric structure [5][7]. Therefore, FONPs are a new and promising nonlinear optical material, which can be widely applied for various photonics applications. The novel materials can be applied as a saturable absorber (SA) in fiber

Polydopamine-coated Au nanorods for targeted fluorescent cell imaging and photothermal therapy

• Boris N. Khlebtsov,
• Andrey M. Burov,
• Timofey E. Pylaev and
• Nikolai G. Khlebtsov

Beilstein J. Nanotechnol. 2019, 10, 794–803, doi:10.3762/bjnano.10.79

• photothermal effects Notably, the AuNR-PDA-R123-folate not only served as fluorescent imaging agent, but it was also employed as a NIR light absorber in photothermal laser therapy. To compare the photothermal properties of PDA-coated nanorods with PEG-coated nanorods, we added 200 µL of AuNR-PDA-R123-folate or

Renewable energy conversion using nano- and microstructured materials

• Harry Mönig and
• Martina Schmid

Beilstein J. Nanotechnol. 2019, 10, 771–773, doi:10.3762/bjnano.10.76

• desirable to use raw materials from cheap earth-abundant elements [15] or to minimize the amount of absorber materials by a combination with optics for efficient light collection [4][16] in order to achieve environmentally friendly production and recycling cycles. This also implies that substances with a

Nanocomposite–parylene C thin films with high dielectric constant and low losses for future organic electronic devices

• Marwa Mokni,
• Gianluigi Maggioni,
• Abdelkader Kahouli,
• Sara M. Carturan,
• Walter Raniero and
• Alain Sylvestre

Beilstein J. Nanotechnol. 2019, 10, 428–441, doi:10.3762/bjnano.10.42

• , as already observed in the case of co-deposition of UV absorber and parylene [56]. When the shutter is open, the deposition rate further increases (samples A, B and C) showing that the plasma effect on the monomer flow is more pronounced. The deposition rate reaches a plateau for the remaining

•  2 the data for our set of samples (black squares) are compared with those of parylene samples deposited without plasma (blue squares, from [56]) and those without plasma but with co-deposition of UV-absorber (red squares, from [56]). Figure 2 highlights the good linear correlation between film

• RBS thickness, the samples deposited with plasma have a higher physical thickness. This means that the plasma gives rise to a decrease of the film density, as already found in the case of samples obtained by co-deposition of parylene and UV-absorber (red squares), the thickness of which is closer to

Geometrical optimisation of core–shell nanowire arrays for enhanced absorption in thin crystalline silicon heterojunction solar cells

• Robin Vismara,
• Olindo Isabella,
• Andrea Ingenito,
• Fai Tong Si and
• Miro Zeman

Beilstein J. Nanotechnol. 2019, 10, 322–331, doi:10.3762/bjnano.10.31

• illumination conditions, by exciting resonances inside the absorber layer. However, passivation of nanowires is critical to further improve the efficiency of such devices. Keywords: heterojunction; nanowires; optical modelling; photovoltaics; silicon; Introduction The implementation of effective and low-cost

• light trapping schemes is of paramount importance for the development of high-efficiency thin silicon solar cells. The most common approach is the texturing of interfaces, to increase the path length of light inside the absorber. This allows for the use of thinner absorbers, which can decrease

• intensity inside the device, resulting in the enhancement of light absorption [4]. Of particular interest is the employment of elongated nanostructures, such as nanowire arrays. While their nanoscale dimensions can excite various types of resonances of the EM field within the absorber, such as wave-guiding

Uniform Sb₂S₃ optical coatings by chemical spray method

• Jako S. Eensalu,
• Atanas Katerski,
• Erki Kärber,
• Ilona Oja Acik,
• Arvo Mere and
• Malle Krunks

Beilstein J. Nanotechnol. 2019, 10, 198–210, doi:10.3762/bjnano.10.18

• sulfide (Sb2S3), an environmentally benign material, has been prepared by various deposition methods for use as a solar absorber due to its direct band gap of ≈1.7 eV and high absorption coefficient in the visible light spectrum (1.8 × 105 cm−1 at 450 nm). Rapid, scalable, economically viable and

• controllable in-air growth of continuous, uniform, polycrystalline Sb2S3 absorber layers has not yet been accomplished. This could be achieved with chemical spray pyrolysis, a robust chemical method for deposition of thin films. We applied a two-stage process to produce continuous Sb2S3 optical coatings with

• environmentally benign material. As Sb and S are abundant elements in the Earth’s crust, enough raw materials can be supplied to manufacture large quantities of Sb2S3 in the long term. Sb2S3 can be applied as the inorganic absorber in solar cells due to its direct band gap of ≈1.7 eV [1][2]. Sb2S3, prepared by a

Zn/F-doped tin oxide nanoparticles synthesized by laser pyrolysis: structural and optical properties

• Florian Dumitrache,
• Iuliana P. Morjan,
• Elena Dutu,
• Ion Morjan,
• Claudiu Teodor Fleaca,
• Monica Scarisoreanu,
• Alina Ilie,
• Marius Dumitru,
• Cristian Mihailescu,
• Adriana Smarandache and
• Gabriel Prodan

Beilstein J. Nanotechnol. 2019, 10, 9–21, doi:10.3762/bjnano.10.2

• laser wavelength, which makes the introduction of a laser energy absorber (sensitizer) such as SF6 necessary. The SF6 molecules absorb part of the infrared laser beam energy and distribute it through collisions to the other gas species in the irradiation area. Thus, the reactive mixture very quickly

Femtosecond laser-assisted fabrication of chalcopyrite micro-concentrator photovoltaics

• Franziska Ringleb,
• Stefan Andree,
• Berit Heidmann,
• Jörn Bonse,
• Katharina Eylers,
• Owen Ernst,
• Torsten Boeck,
• Martina Schmid and
• Jörg Krüger

Beilstein J. Nanotechnol. 2018, 9, 3025–3038, doi:10.3762/bjnano.9.281

• enhance the efficiency of planar-cell technologies while saving absorber material. Here, two laser-based bottom-up processes for the fabrication of regular arrays of CuInSe2 and Cu(In,Ga)Se2 microabsorber islands are presented, namely one approach based on nucleation and one based on laser-induced forward

• for low-cost solar power. In the present review, we provide an overview about research carried out on micro-concentrator solar cells – a new cell concept that has been emerging in recent years – using Cu(In,Ga)Se2 (CIGSe) as absorber material. The review focuses on two different laser-based

• state of the art. The electric back contact (molybdenum) covered with the highly-efficient light-absorber (CIGSe) on top is deposited on a carrier material (glass). A buffer layer (CdS), a window layer consisting of an intrinsic ZnO layer (ZnO) and an aluminum-doped ZnO layer (Al:ZnO) as transparent

Oriented zinc oxide nanorods: A novel saturable absorber for lasers in the near-infrared

• Pavel Loiko,
• Tanujjal Bora,
• Josep Maria Serres,
• Haohai Yu,
• Magdalena Aguiló,
• Francesc Díaz,
• Uwe Griebner,
• Valentin Petrov,
• Xavier Mateos and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2018, 9, 2730–2740, doi:10.3762/bjnano.9.255

• based on randomly oriented SWCNTs in a PMMA film (all of them deposited on a 1 mm-thick fused silica substrate), and a commercial transmission-type semiconductor saturable absorber (SESA, for Tm laser). For the Yb laser, the performance of all such nanostructured SAs is modest. In general, this is

Optimization of Mo/Cr bilayer back contacts for thin-film solar cells

• Nima Khoshsirat,
• Fawad Ali,
• Vincent Tiing Tiong,
• Mojtaba Amjadipour,
• Hongxia Wang,
• Mahnaz Shafiei and
• Nunzio Motta

Beilstein J. Nanotechnol. 2018, 9, 2700–2707, doi:10.3762/bjnano.9.252

• of the film to the substrate and the Mo back contact layer could peel off from the substrate during the absorber layer growth at high temperatures or during the deposition of the buffer layer, which most commonly involves a wet chemical process. Moreover, the thickness of the bilayer Mo film needs to

• substrate to the absorber layer and its effect on the adhesion of the back contact was not studied. In spite of the importance of this topic for the development of thin-film solar cells, there are very few reports regarding the application of Cr as an adhesion layer in back contacts [29][30]. Notably, the

• influence of Cr on the properties of the back contact and on the total performance of the solar cell is still a subject of debate and some studies negatively correlates Cr with a low performance of the cell due to its diffusion in the absorber layer [31]. In this work we exploit the adhesive properties of

Thickness-dependent photoelectrochemical properties of a semitransparent Co₃O₄ photocathode

• Malkeshkumar Patel and
• Joondong Kim

Beilstein J. Nanotechnol. 2018, 9, 2432–2442, doi:10.3762/bjnano.9.228

• -absorber materials such as metal sulfides and metal oxides via heterojunction. The photocurrent can be further improved by three approaches: The first one is to improve the optoelectronic processes in the Co3O4 film [39], the second is to improve the composition of the heterojunction, i.e. Co3O4/Ga2O3 [42

Performance analysis of rigorous coupled-wave analysis and its integration in a coupled modeling approach for optical simulation of complete heterojunction silicon solar cells

• Ziga Lokar,
• Benjamin Lipovsek,
• Marko Topic and
• Janez Krc

Beilstein J. Nanotechnol. 2018, 9, 2315–2329, doi:10.3762/bjnano.9.216

• refraction). The latter is especially important in solar cells where indirect semiconductors such as silicon (Si) are used as an absorber layer, where the absorption coefficient at the photon energy approaching the value of energy bandgap is small. Furthermore, efficient light management is important in

• (EVA) encapsulation (Figure 3). The front of the basic solar cell structure consists of transparent conductive oxide (e.g., indium tin oxide (ITO)), a thin p-doped and intrinsic amorphous silicon (a-Si:H) layer for electrical passivation, a slightly n-doped crystalline Si (c-Si) wafer (absorber), and

Lead-free hybrid perovskites for photovoltaics

• Oleksandr Stroyuk

Beilstein J. Nanotechnol. 2018, 9, 2209–2235, doi:10.3762/bjnano.9.207

• market is dominated by silicon solar cells with top light-to-current conversion efficiencies reaching ≈27% [1]. As an alternative to the Si-based cells requiring a relatively thick absorber layer due to the indirect character of electron transitions in Si, direct-bandgap metal chalcogenide semiconductors

• the HP composition [92]. By simultaneously tuning the composition of Pb–Sn and halide components, a solar light absorber was designed with a bandgap of 1.35 eV ideal for the solar light harvesting. The inverted cells based on MAPb0.5Sn0.5(I0.8Br0.2)3 demonstrated PCEs of up to 17.63% [70]. A

• leaving large room for further improvement of the structural quality of the perovskite absorber layer. The substitution of a mere 2% lead with Sr(II) in CsPbI2Br HP was found to result in a spectacular PCE increase from 6.6% to 10.1% and an enhancement of the thermal HP stability [102]. Strontium ions

Spin-coated planar Sb₂S₃ hybrid solar cells approaching 5% efficiency

• Pascal Kaienburg,
• Benjamin Klingebiel and
• Thomas Kirchartz

Beilstein J. Nanotechnol. 2018, 9, 2114–2124, doi:10.3762/bjnano.9.200

• demonstrated an efficiency exceeding 7% when assembled in an extremely thin absorber configuration deposited via chemical bath deposition. More recently, less complex, planar geometries were obtained from simple spin-coating approaches, but the device efficiency still lags behind. We compare two processing

• ; hole transport material; solar cell; Introduction Antimony sulfide (Sb2S3) is a promising high band gap light absorber for solar cells [1][2][3][4][5]. The record efficiency of 7.5% [6] is comparable to that of other less investigated materials, such as the best lead-free perovskites [7], Cu2O [8] and

• needed. Two basic factors that impact the solar cell performance of a given material are the device architecture, which defines the mechanism of charge separation, and the deposition method for the absorber, which affects the film and electronic material quality. Sb2S3 is commonly applied in an extremely

Know your full potential: Quantitative Kelvin probe force microscopy on nanoscale electrical devices

• Amelie Axt,
• Ilka M. Hermes,
• Victor W. Bergmann,
• Niklas Tausendpfund and
• Stefan A. L. Weber

Beilstein J. Nanotechnol. 2018, 9, 1809–1819, doi:10.3762/bjnano.9.172

• , visualized by the red and blue line, respectively. The cell consisted of a fluorine-doped tin oxide (FTO) electrode, a compact TiO2 electron extraction layer and a mesoscopic TiO2 layer (meso) filled with the perovskite light-absorber methylammonium lead iodide (MAPI). The mesoscopic layer was followed by a

Tailoring polarization and magnetization of absorbing terahertz metamaterials using a cut-wire sandwich structure

• Hadi Teguh Yudistira,
• Shuo Liu,
• Tie Jun Cui and
• Han Zhang

Beilstein J. Nanotechnol. 2018, 9, 1437–1447, doi:10.3762/bjnano.9.136

• this work, we designed, fabricated and characterized a cut-wire sandwich device capable of tailoring the polarization and magnetization separately, thereby providing a promising recipe for achieving specific application objectives, such as a high-performance absorber. Accumulated charges effectively

• other frequency ranges because polarization and magnetization can now be selectively controlled in a straightforward manner. Keywords: absorber; cut-wire; metamaterial; terahertz; Introduction The terahertz spectrum is located between the infrared and microwave spectrum. This part of the spectrum has

• works on metamaterial absorbers have been presented such as split-ring resonators [15], electric-field-coupled (ELC) resonators [16], lossy cut-wire bars [17], and donut-type resonators [18]. Most previous works on the perfect absorber have been explained by interference theory [19][20][21][22][23], for

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

• render MnPc an appropriate absorber material in organic photovoltaic cells in contrast to, e.g., CuPc. Evolution of the valence-band PES data (He Iα) as a function of a) MnPc deposition onto C60 and b) C60 deposition onto MnPc. Additionally, the bottom spectrum represents the freshly prepared Au(100

Study of the surface properties of ZnO nanocolumns used for thin-film solar cells

• Neda Neykova,
• Jiri Stuchlik,
• Karel Hruska,
• Ales Poruba,
• Zdenek Remes and
• Ognen Pop-Georgievski

Beilstein J. Nanotechnol. 2017, 8, 446–451, doi:10.3762/bjnano.8.48

• region of silicon above approximately 650 nm, leading to efficiencies well above 13% at the cell level and above 12% at the module level [3][4]. However, the photo-generated current, determined by light absorption, is limited by the drift of generated electrons and holes across the absorber layer. Thus

• vertical geometry of these textures, the optical thickness is dictated by the height of the NCs, such that most of the light traversing the cell sees an absorber-layer thickness approximately equal to the NC height. In contrast, as the front and back TCO contacts are interpenetrating, the inter-electrode

Nanocrystalline TiO₂/SnO₂ heterostructures for gas sensing

• Barbara Lyson-Sypien,
• Anna Kusior,
• Mieczylaw Rekas,
• Jan Zukrowski,
• Marta Gajewska,
• Katarzyna Michalow-Mauke,
• Thomas Graule,
• Marta Radecka and
• Katarzyna Zakrzewska

Beilstein J. Nanotechnol. 2017, 8, 108–122, doi:10.3762/bjnano.8.12

• and CaSnO3 as source. The Mössbauer spectra were fitted using a transmission integral in order to take into account the absorber thickness effects. The spectra were refined with quadrupole doublets of Lorentzian lines assuming a non-zero value of the electric field gradient at the tin site. Hyperfine

Grazing-incidence optical magnetic recording with super-resolution

• Gunther Scheunert,
• Sidney. R. Cohen,
• René Kullock,
• Ryan McCarron,
• Katya Rechev,
• Ifat Kaplan-Ashiri,
• Ora Bitton,
• Paul Dawson,
• Bert Hecht and
• Dan Oron

Beilstein J. Nanotechnol. 2017, 8, 28–37, doi:10.3762/bjnano.8.4

• (~70%). The Co layer is the single greatest absorber in the stack by a factor of 2 (Figure 7, inset), which is ideal for energy transfer to the desired magnetic layer only. The inset further shows the ideal wavelength within the visible regime to be as short as possible for maximal coupling efficiency

Sb₂S₃ grown by ultrasonic spray pyrolysis and its application in a hybrid solar cell

• Erki Kärber,
• Atanas Katerski,
• Ilona Oja Acik,
• Arvo Mere,
• Valdek Mikli and
• Malle Krunks

Beilstein J. Nanotechnol. 2016, 7, 1662–1673, doi:10.3762/bjnano.7.158

• /cm2, a fill factor of 42% and a conversion efficiency of 1.3%. Conversion efficiencies up to 1.9% were obtained from solar cells with smaller areas. Keywords: absorber; chemical spray pyrolysis (CSP); hybrid solar cell; stibnite (Sb2S3); ultrasonic atomization; Introduction A solution-based

• technology coupled with earth abundant materials is an attractive path for affordable next-generation solar cells. The present paper relies on the recently proven concept of TiO2/Sb2S3/P3HT solar cells [1][2][3][4][5][6][7][8][9][10][11][12], in which Sb2S3 is the light absorber, also called the sensitizer

• Sb2S3 sensitizer, yielded conversion efficiencies above 3% [15][16]. The central part of the particular system, the Sb2S3 absorber, has so far been produced mainly by chemical bath deposition (CBD) for which the presence of impurities such as antimony hydroxide is inherent, and it is essential to use

Functional diversity of resilin in Arthropoda

• Jan Michels,
• Esther Appel and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2016, 7, 1241–1259, doi:10.3762/bjnano.7.115

• hind legs [76]. The buckling region is located in an area where the bending moment during jumping and kicking is high. When a hindleg slips during jumping or misses a target during kicking, this structure can buckle and thereby act as a shock absorber by dissipating energy that would otherwise have to