Structural and electronic properties of SnO₂ doped with non-metal elements

• Jianyuan Yu,
• Yingeng Wang,
• Yan Huang,
• Xiuwen Wang,
• Jing Guo,
• Jingkai Yang and
• Hongli Zhao

Beilstein J. Nanotechnol. 2020, 11, 1321–1328, doi:10.3762/bjnano.11.116

• is that F-doped SnO2 has the lowest defect binding energy. The doping with B and S introduced additional defect energy levels within the forbidden bandgap, which improved the crystal conductivity. The Fermi level shifts up due to the doping with B, F, and S, while the Fermi level of SnO2 doped with C

• (substituting O) can effectively increase the carrier concentration and improve the conductivity. Majumder successfully prepared SnO2:F thin films using spray pyrolysis with SnF2 as the precursor. By adjusting the concentration of the precursor solution, doped SnO2 films with different properties were obtained

• conduction band. The electronic structure including the energy band structure, total density of states and partial wave state density of the doped system are shown in Figure 2. For SnO2, the Fermi energy level is at the top of the valence band, indicating that the conductivity of SnO2 is low. The conduction

Magnetohydrodynamic stagnation point on a Casson nanofluid flow over a radially stretching sheet

• Ganji Narender,
• Kamatam Govardhan and
• Gobburu Sreedhar Sarma

Beilstein J. Nanotechnol. 2020, 11, 1303–1315, doi:10.3762/bjnano.11.114

• generation, DT is the thermophoresis diffusion coefficient, σ is the electrical conductivity, β represents the Casson fluid parameter, and T represents the nanofluid temperature. The following similarity variables are taken into consideration: Finally, the ODEs describing the proposed flow problem can be

Structure and electrochemical performance of electrospun-ordered porous carbon/graphene composite nanofibers

• Yi Wang,
• Yanhua Song,
• Chengwei Ye and
• Lan Xu

Beilstein J. Nanotechnol. 2020, 11, 1280–1290, doi:10.3762/bjnano.11.112

• specific surface area. The increase in the specific surface area of the electrode due to increased porosity facilitates ion transportation, which increases the conductivity of monolithic electrodes [24][25][26]. Although the porous carbon nanofibers have a high specific surface area, their low electrical

• conductivity impedes their use in high-power-density supercapacitors. Therefore, by adding high-performance conductive materials one can enhance the electrochemical performance of carbon nanofibers. Experiments have shown that by introducing graphene into the carbon matrix, various mechanical and

• electrical conductivity and good biocompatibility [28][29][30]. Studies have indicated that graphene still maintains an excellent charge/discharge performance at an electrochemical scan rate of almost 250 mV·s−1 [31] and has an excellent cycle performance and fast charge/discharge characteristics [32

High permittivity, breakdown strength, and energy storage density of polythiophene-encapsulated BaTiO₃ nanoparticles

• Adnanullah Khan,
• Amir Habib and
• Adeel Afzal

Beilstein J. Nanotechnol. 2020, 11, 1190–1197, doi:10.3762/bjnano.11.103

• exhibit irregular surface profile, which confirms the occurrence of sub-micrometer clusters and nanoscale particles on the surface. The permittivity or dielectric constant (ε′), loss tangent (tan δ), dielectric loss (ε″), and ac conductivity (σac) of the synthesized materials are measured as a function of

• resistivity of grain boundaries, more energy is required for electron hopping, thus, increasing the loss [27][28]. In the high frequency region that corresponds to the higher conductivity, energy required for the hopping of electrons is less and therefore, the loss decreases [27][28]. Dielectric loss is an

• conductivity of BTO and core–shell BTO-PTh nanoparticles. The ac conductivity as a function of the frequency is shown in Figure 6d. It is observed that BTO-PTh nanoparticles have a lower ac conductivity than BTO, and the ac conductivity increases linearly with the frequency of the applied field. At lower

Nonadiabatic superconductivity in a Li-intercalated hexagonal boron nitride bilayer

• Kamila A. Szewczyk,
• Izabela A. Domagalska,
• Artur P. Durajski and
• Radosław Szczęśniak

Beilstein J. Nanotechnol. 2020, 11, 1178–1189, doi:10.3762/bjnano.11.102

• result is radically different from the data obtained for graphene/SiO2 [33]. In addition, hBN monolayers exhibit a high temperature stability, a low dielectric constant (ε = 3–4), and a high thermal conductivity [34]. The band gap of hBN is about 5.9 eV [35]. Furthermore, which is also important, hBN is

Thermophoretic tweezers for single nanoparticle manipulation

• Jošt Stergar and
• Natan Osterman

Beilstein J. Nanotechnol. 2020, 11, 1126–1133, doi:10.3762/bjnano.11.97

•  1b,c). Temperature measurements are performed using the temperature-dependent fluorescence of sulforhodamine B (Radiant dyes Chemie), which is calibrated in an independent measurement (accuracy ±2 K). Since the sapphire glass with a high thermal conductivity helps cooling the thin sample film, the

A few-layer graphene/chlorin e6 hybrid nanomaterial and its application in photodynamic therapy against Candida albicans

• Selene Acosta,
• Carlos Moreno-Aguilar,
• Dania Hernández-Sánchez,
• Beatriz Morales-Cruzado,
• Erick Sarmiento-Gomez,
• Carla Bittencourt,
• Luis Octavio Sánchez-Vargas and
• Mildred Quintana

Beilstein J. Nanotechnol. 2020, 11, 1054–1061, doi:10.3762/bjnano.11.90

• , due to their excellent physical and chemical properties (e.g., high surface area, excellent thermal and electric conductivity, high mechanical strength)[19][20][21]. Examples of graphene nanomaterials include single-layer graphene, few-layer graphene (FLG), graphene oxide (GO), and the reduced form of

• GO (rGO) [22]. GO and rGO have been conjugated to several photosensitizers to enhance their performance in PDT [15][17][23][24][25]. However, for enhancing the characteristics of a Ps, the properties of graphene, such as electrical conductivity and chemical stability are very important, and these

Excitonic and electronic transitions in Me–Sb₂Se₃ structures

• Nicolae N. Syrbu,
• Victor V. Zalamai,
• Ivan G. Stamov and
• Stepan I. Beril

Beilstein J. Nanotechnol. 2020, 11, 1045–1053, doi:10.3762/bjnano.11.89

• that is characteristic of the conductivity hopping mechanism which in turn is independent of the metal type and the deposition method used. The photocurrent increases when the energy of the photons increases in the Schottky barriers when the transparent contacts are illuminated. The structures with the

A new photodetector structure based on graphene nanomeshes: an ab initio study

• Babak Sakkaki,
• Hassan Rasooli Saghai,
• Ghafar Darvish and
• Mehdi Khatir

Beilstein J. Nanotechnol. 2020, 11, 1036–1044, doi:10.3762/bjnano.11.88

• among experimental and theoretical researchers. Electrical properties such as a charge mobility in the range of 105 cm2·V−1·s−1, a minimum conductivity at the Dirac point of 4e2/πh (at low temperature), and remarkable optical properties such as linear dispersion of the Dirac electrons make broadband

• particular, photodetectors based on graphene will have a large dark current due to the conductivity of graphene even without incident photons [2]. An energy gap in the band structure of graphene can be created using quantum confinement effects via creating graphene nanoribbons (GNRs) with a width of

• . According to our calculations, the bandgap of A4Z6-6 and A4Z6-24 is 0.49 and 0.92 eV, respectively. The Fermi level in A4Z6-6 is closer to the conduction band, which increases the distribution of carriers and the conductivity of this material. At the end of the paper, we compare our detector to some state

Gas-sensing features of nanostructured tellurium thin films

• Dumitru Tsiulyanu

Beilstein J. Nanotechnol. 2020, 11, 1010–1018, doi:10.3762/bjnano.11.85

• different operating temperatures with respect to scanning electron microscopy and X-ray diffraction analyses. It was shown that both types of films interacted with nitrogen dioxide, which resulted in a decrease of electrical conductivity. The gas sensitivity, as well as the response and recovery times

• with an approximate average size of 100 nm. Assuming the neutrality of the Au/Te contacts, the electrical conductivity of the film is mainly controlled by the bulk, surface and grain boundary resistances. On the other hand, due to the peculiarities of chalcogens and chalcogenide materials [1][30], a

Effect of magnetic field, heat generation and absorption on nanofluid flow over a nonlinear stretching sheet

• Santoshi Misra and
• Govardhan Kamatam

Beilstein J. Nanotechnol. 2020, 11, 976–990, doi:10.3762/bjnano.11.82

• thermal conductivity and convective heat transfer performance of base fluids such as water, ethylene, glycol, etc. This takes place due to the intense and rigorous distribution of nanoparticle Brownian motion within the base fluid, thus enhancing the uniformity, conductance and properties which have paved

• expansion coefficient, ρp is the particle density, σ denotes the nanofluid electrical conductivity, B0 denotes the magnetic induction, vw denotes the suction/injection velocity and Q0 (Q) denotes the heat generation (absorption) coefficient. us in Equation 8 represents the slip velocity, given as which is

Band tail state related photoluminescence and photoresponse of ZnMgO solid solution nanostructured films

• Vadim Morari,
• Aida Pantazi,
• Nicolai Curmei,
• Vitalie Postolache,
• Emil V. Rusu,
• Marius Enachescu,
• Ion M. Tiginyanu and
• Veaceslav V. Ursaki

Beilstein J. Nanotechnol. 2020, 11, 899–910, doi:10.3762/bjnano.11.75

• different numbers of technological steps and the different temperature of the substrate during the deposition processes. In our opinion, the higher resistivity of the films prepared by spin coating as compared to those obtained by spray pyrolysis indicates a higher degree of conductivity compensation, due

• amplitude of potential fluctuations is determined by the degree of doping and conductivity compensation. In porous semiconductors the amplitude is determined by the degree of porosity, while it is a function of local fluctuations of the composition in solid solutions, including ZnMgO. The observation of the

A Josephson junction based on a highly disordered superconductor/low-resistivity normal metal bilayer

• Pavel M. Marychev and
• Denis Yu. Vodolazov

Beilstein J. Nanotechnol. 2020, 11, 858–865, doi:10.3762/bjnano.11.71

• suppressed. It allows us to use normal-state heat conductivity both in the SN and the S region in the heat conductance equation for the calculation of δTe. This is in contrast to S-N-S and S’-S-S’ junctions where heat conductivity is suppressed in the superconducting banks. In our model Joule dissipation is

• : where is the electron heat conductivity of the S layer in the normal state, and N(0) is the one-spin density of states on the Fermi level, is the thermal healing length, β = [γτesc 450ζ(5)T/[τ0π4Tc0], ζ(5) ≈ 1.03, τesc is the escape time of nonequilibrium phonons to the substrate, γ = 8π2Ce(Tc0)/Cp(Tc0

Light–matter interactions in two-dimensional layered WSe₂ for gauging evolution of phonon dynamics

• Avra S. Bandyopadhyay,
• Chandan Biswas and
• Anupama B. Kaul

Beilstein J. Nanotechnol. 2020, 11, 782–797, doi:10.3762/bjnano.11.63

• external stimuli. For example, external radiation could be in the form of heat or optical energy, which also directly influences properties such as the electronic and optoelectronic transport and the thermal conductivity of the material. In this work, we have conducted an in-depth analysis of the phonon

• dependence of the Raman shifts in 2D TMDCs such as MoS2 [20][21][22][23][24], and WS2 [25][26] have been extensively studied over a wide temperature range from which properties such as thermal conductivity was deciphered [23][27]. On the contrary, the temperature-dependent Raman analysis of WSe2 is rather

• phonon density increases as T3, while in a quantum confined system such as the 1L case, the phonon density is not as strong a function of T. This also has a direct influence on the thermal conductivity of quantum-confined 1D structures where the thermal conductivity should be high and not vary

Nickel nanoparticles supported on a covalent triazine framework as electrocatalyst for oxygen evolution reaction and oxygen reduction reactions

• Secil Öztürk,
• Yu-Xuan Xiao,
• Dennis Dietrich,
• Beatriz Giesen,
• Juri Barthel,
• Jie Ying,
• Xiao-Yu Yang and
• Christoph Janiak

Beilstein J. Nanotechnol. 2020, 11, 770–781, doi:10.3762/bjnano.11.62

• of nickel into the voids of CTF-1 (Table S2, Supporting Information File 1). Still, surface area and porosity of the Ni/CTF-1 composites are high, which are important features. It is accepted that conductivity plays a more important role, yet high surface area and porosity are known to enhance the

• exposure of active sites and to improve the ion and charge transfer through nanochannels together with the electron-conductive medium [46]. Here, the increase of conductivity and surface area from CTF-1-400 to CTF-1-600 go in the same direction and cannot be differentiated regarding their role in improving

• admixture of Ni species with low activity in the composite materials. The better OER performance of CTF-1-600 over the CTF-1-400 materials is attributed to the better conductivity of the former (as given by the Nyquist plot in Figure 7) and its faster ion and charge transfer together with its higher

Effect of Ag loading position on the photocatalytic performance of TiO₂ nanocolumn arrays

• Jinghan Xu,
• Yanqi Liu and
• Yan Zhao

Beilstein J. Nanotechnol. 2020, 11, 717–728, doi:10.3762/bjnano.11.59

• the absence of photogenerated carriers. Only the energetic electrons produced by Ag could participate in the catalytic reaction, as shown in Figure 9c. The above results show that more photo-generated carriers are generated on the AFT structure, and the good conductivity of Ag promotes the separation

Structural optical and electrical properties of a transparent conductive ITO/Al–Ag/ITO multilayer contact

• Aliyu Kabiru Isiyaku,
• Ahmad Hadi Ali and
• Nafarizal Nayan

Beilstein J. Nanotechnol. 2020, 11, 695–702, doi:10.3762/bjnano.11.57

• importance. The inclusion of a thin metal film between a top and a bottom ITO layer to form a multilayer structure has been explored recently for efficient photoelectric devices [7]. The multilayer structure not only improves the conductivity of the contact but also make the device cost-effective since less

• roughness is attributed to the increasing grain sizes [35]. The large grain sizes of IAAI films reduce the number of grain boundaries and thus the scattering at grain boundaries. This improves the carrier mobility leading to an increased electrical conductivity of the films. The surface morphology of the

• heat treatment lowers the trade-off between transparency and conductivity by reducing structural defects in the films. The sheet resistance of the multilayer structure of the IAAI film can be expressed as [29]: where is the total sheet resistance of the IAAI film, RAl and RAg are the sheet resistance

Exfoliation in a low boiling point solvent and electrochemical applications of MoO₃

• Matangi Sricharan,
• Bikesh Gupta,
• Sreejesh Moolayadukkam and
• H. S. S. Ramakrishna Matte

Beilstein J. Nanotechnol. 2020, 11, 662–670, doi:10.3762/bjnano.11.52

• poor intrinsic electronic conductivity of the MoO3 [24]. In order to enhance the electrochemical properties, composites of exfoliated MoO3 nanosheets and conducting carbon black (CB) were prepared. As shown in Figure 3a, well-defined oxidation and reduction peaks are observed after the addition of 2 wt

• response with a small iR drop. This can be attributed to the better conductivity after adding CB. To study the stability of the composite, cyclic voltammetry was carried out up to 2000 cycles. Initially, the capacitance increases, which may be attributed to the wetting of the electrode with the electrolyte

Preparation, characterization and photocatalytic performance of heterostructured CuO–ZnO-loaded composite nanofiber membranes

• Wei Fang,
• Liang Yu and
• Lan Xu

Beilstein J. Nanotechnol. 2020, 11, 631–650, doi:10.3762/bjnano.11.50

• widely used to fabricate nanofiber membranes because of its good spinnability, electrical conductivity, and heat resistance. However, carbonized PAN nanofiber membranes usually have poor mechanical properties. Polyvinylidene fluoride (PVDF) has better mechanical properties but a lower melting point

Adsorptive removal of bulky dye molecules from water with mesoporous polyaniline-derived carbon

• Hyung Jun An,
• Jong Min Park,
• Nazmul Abedin Khan and
• Sung Hwa Jhung

Beilstein J. Nanotechnol. 2020, 11, 597–605, doi:10.3762/bjnano.11.47

• synthesis, high conductivity and nitrogen content. Porous carbon materials, with high porosity and nitrogen content, have also been obtained from PANI. In other words, functional carbon, for catalysts and supercapacitors can be derived from high temperature carbonization of PANI, especially in the co

Comparison of fresh and aged lithium iron phosphate cathodes using a tailored electrochemical strain microscopy technique

• Matthias Simolka,
• Hanno Kaess and
• Kaspar Andreas Friedrich

Beilstein J. Nanotechnol. 2020, 11, 583–596, doi:10.3762/bjnano.11.46

• additional mechanical (stiffness, elasticity), electrical (conductivity, surface potential), electrochemical (reactivity, mobility and activity), mechanoelectrical (piezoelectricity) and chemical (chemical bonding) material properties. In situ AFM imaging of the sample topography is often used to study the

• ionic conductivity. Yang et al. observed a similar decrease of the ESM signal intensity after scanning the same location several times, which they attributed to either changing ionic concentration or degradation of the electrochemical activity [43]. The second location shows a linear increase of the ESM

Interfacial charge transfer processes in 2D and 3D semiconducting hybrid perovskites: azobenzene as photoswitchable ligand

• Nicole Fillafer,
• Tobias Seewald,
• Lukas Schmidt-Mende and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2020, 11, 466–479, doi:10.3762/bjnano.11.38

• the present work the combination of a lead-containing hybrid perovskite with π-conjugated organic molecules is of importance. Functionalizing hybrid perovskites with conjugated π systems improves not only the optoelectronical properties and stability but as well the conductivity [16][17][18][19][20

Current measurements in the intermittent-contact mode of atomic force microscopy using the Fourier method: a feasibility analysis

• Berkin Uluutku and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2020, 11, 453–465, doi:10.3762/bjnano.11.37

• surface properties, such as topography, viscoelasticity, electrical potential and conductivity. Some of these properties are measured using contact methods (static contact or intermittent contact), while others are measured using noncontact methods. Some properties can be measured using different

• approaches. Conductivity, in particular, is mapped using the contact-mode method. However, this modality can be destructive to delicate samples, since it involves continuously dragging the cantilever tip on the surface during the raster scan, while a constant tip–sample force is applied. In this paper we

• significant instrumentation challenges are anticipated, the modelling results are promising and suggest that Fourier-based higher-harmonics current measurement may enable the development of a reliable intermittent-contact conductive AFM method. Keywords: atomic force microscopy (AFM); conductivity; current

An advanced structural characterization of templated meso-macroporous carbon monoliths by small- and wide-angle scattering techniques

• Felix M. Badaczewski,
• Marc O. Loeh,
• Torben Pfaff,
• Dirk Wallacher,
• Daniel Clemens and
• Bernd M. Smarsly

Beilstein J. Nanotechnol. 2020, 11, 310–322, doi:10.3762/bjnano.11.23

• ][7][8]. The turbostratic microstructure of these “non-graphitic” carbon materials combined with variable conductivity and a significant nanoscale disordered porosity are typical features of this kind of carbon materials. Templating strategies are meanwhile well established to endow carbon materials

• structures [51][52][53][54]. Key properties of glassy carbon materials, such as thermal conductivity, chemical resistance, hardness, density, and coefficient of thermal expansion are closely related to the carbon microstructure and the porosity. Resin-based carbon materials are known to possess a substantial

• °C, for which in situ SANS experiments were performed comparing the evacuated samples with the filled state. A temperature of 3000 °C was chosen, because at this treatment temperature graphitized carbon forms, which possesses advantageous properties such as high electronic conductivity. The porosity

Anomalous current–voltage characteristics of SFIFS Josephson junctions with weak ferromagnetic interlayers

• Tairzhan Karabassov,
• Anastasia V. Guravova,
• Aleksei Yu. Kuzin,
• Elena A. Kazakova,
• Shiro Kawabata,
• Boris G. Lvov and
• Andrey S. Vasenko

Beilstein J. Nanotechnol. 2020, 11, 252–262, doi:10.3762/bjnano.11.19

• interface [86][87][88]. Here σn is the conductivity of the F layer and is the coherence length, where Tc is the critical temperature of the superconductor S (here and below we assume ℏ = kB = 1). In this paper we consider the diffusive limit, when the elastic scattering length is much smaller than the

• with corresponding boundary conditions. At the S/F interfaces we apply the Kupriyanov–Lukichev boundary conditions. For example, at the left S/F interface they are written as [86], Similar equations can be written at the right S/F interface at x = df2. Here γ = ξsσn/ξnσs, where σs is the conductivity