Unveiling the nature of atomic defects in graphene on a metal surface

• Karl Rothe,
• Nicolas Néel and
• Jörg Kröger

Beilstein J. Nanotechnol. 2024, 15, 416–425, doi:10.3762/bjnano.15.37

• the tip–graphene and graphene–surface hybridization [23][65]. Therefore, simulations of the non-equilibrium charge transport across the junction are required for a detailed understanding of the observed current traces. Conclusion A combination of STM and AFM experiments unravels the nature of defects

Controllable physicochemical properties of WO_x thin films grown under glancing angle

• Rupam Mandal,
• Aparajita Mandal,
• Alapan Dutta,
• Rengasamy Sivakumar,
• Sanjeev Kumar Srivastava and
• Tapobrata Som

Beilstein J. Nanotechnol. 2024, 15, 350–359, doi:10.3762/bjnano.15.31

• conduction across the heterojunction with increasing film thickness indicates a possible role of oxygen vacancies in facilitating smooth charge transport till the thickness reaches 30 nm, above which the series resistance effect within the WOx film starts to dominate. Overall, this study demonstrates a wide

CdSe/ZnS quantum dots as a booster in the active layer of distributed ternary organic photovoltaics

• Gabriela Lewińska,
• Piotr Jeleń,
• Zofia Kucia,
• Maciej Sitarz,
• Łukasz Walczak,
• Bartłomiej Szafraniak,
• Jerzy Sanetra and
• Konstanty W. Marszalek

Beilstein J. Nanotechnol. 2024, 15, 144–156, doi:10.3762/bjnano.15.14

• outstanding excitation and optimum charge transport in the mixture. Small-molecule materials, dyes, polymers, fullerenes, and ligands have been introduced as a third component so far. Quantum dots (QDs) are also beneficial materials for ternary solar cells. QDs and nanoparticles as zero-dimensional materials

• recombination, and increased charge transport. This was also demonstrated by Lv and co-workers [65]. The LUMO level of QD600 is lower than that of the donor P3HT, while the other QDs have higher LUMO levels. This difference in LUMO levels poses a challenge for the transportation of electrons to the cathode

• of QD-doped devices was compared to the reference system (ITO/PEDOT:PSS/P3HT:PCBM/aluminium). PEDOT:PSS ([poly(3.4-ethylene dioxythiophene] polystyrene sulfonate) is an intrinsically conductive polymer, a mixture of two ionomers, with a HOMO level equal to 5.17 eV [61]. It is widely used as a charge

Cross-sectional Kelvin probe force microscopy on III–V epitaxial multilayer stacks: challenges and perspectives

• Mattia da Lisca,
• José Alvarez,
• James P. Connolly,
• Nicolas Vaissiere,
• Karim Mekhazni,
• Jean Decobert and
• Jean-Paul Kleider

Beilstein J. Nanotechnol. 2023, 14, 725–737, doi:10.3762/bjnano.14.59

• enhancing device efficiency [10][11]. Consequently, the experimental demonstration of the sensitivity of KPFM to the narrower layers can be crucial for the investigation and comprehension of local surface properties and charge transport mechanisms at interfaces [12]. Within this context, this work presents

Photoelectrochemical water oxidation over TiO₂ nanotubes modified with MoS₂ and g-C₃N₄

• Phuong Hoang Nguyen,
• Thi Minh Cao,
• Tho Truong Nguyen,
• Hien Duy Tong and
• Viet Van Pham

Beilstein J. Nanotechnol. 2022, 13, 1541–1550, doi:10.3762/bjnano.13.127

• chemical, thermal, and charge transport properties, which can shift the light absorption of TiO2 to the visible region [29][30][31][32]. An emerging new material in optoelectronics is g-C3N4 (bandgap of 2.65–2.7 eV) because it has an appropriate band structure with suitable energy levels regarding TiO2

A TiO₂@MWCNTs nanocomposite photoanode for solar-driven water splitting

• Anh Quynh Huu Le,
• Ngoc Nhu Thi Nguyen,
• Hai Duy Tran,
• Van-Huy Nguyen and
• Le-Hai Tran

Beilstein J. Nanotechnol. 2022, 13, 1520–1530, doi:10.3762/bjnano.13.125

• of the electrodes through Nyquist plots, as shown in Figure 8b. The MWCNTs electrode has the lowest arc radius among the prepared electrodes, indicating the fast charge transport on this electrode [36]. A contrastive result is observed for the TiO2 electrode, which could be due to the poor electrical

Recent trends in Bi-based nanomaterials: challenges, fabrication, enhancement techniques, and environmental applications

• Vishal Dutta,
• Ankush Chauhan,
• Ritesh Verma,
• C. Gopalkrishnan and
• Van-Huy Nguyen

Beilstein J. Nanotechnol. 2022, 13, 1316–1336, doi:10.3762/bjnano.13.109

• to improve absorption of visible light, charge carrier segregation, and charge transport effectiveness by combining heterojunction and nanomaterials in photocatalysts constructed with care. As a result, this technique offers much potential for photocatalysis applications [94]. The band arrangement

Rapid fabrication of MgO@g-C₃N₄ heterojunctions for photocatalytic nitric oxide removal

• Minh-Thuan Pham,
• Duyen P. H. Tran,
• Xuan-Thanh Bui and
• Sheng-Jie You

Beilstein J. Nanotechnol. 2022, 13, 1141–1154, doi:10.3762/bjnano.13.96

• bandgap reduction can be attributed to Mg−N bonds in the MgO@g-C3N4 materials, which promote charge transport, thus, increasing the photocatalytic efficiency [33][51]. Generally, smaller bandgaps lead to better light absorption, indicating the high photocatalytic activity of MgO@g-C3N4 under visible light

Ultrafast signatures of magnetic inhomogeneity in Pd_1−xFe_x (x ≤ 0.08) epitaxial thin films

• Andrey V. Petrov,
• Sergey I. Nikitin,
• Lenar R. Tagirov,
• Amir I. Gumarov,
• Igor V. Yanilkin and
• Roman V. Yusupov

Beilstein J. Nanotechnol. 2022, 13, 836–844, doi:10.3762/bjnano.13.74

• of 10 ps can be estimated as 10−9 m/10−11 s = 100 m/s. For the conventional spin diffusion, the spin memory length is where is the diffusion coefficient, τs is the Elliott–Yafet spin-relaxation time [46][47], τ is the charge transport relaxation time, and vF is the Fermi velocity. For the purpose

Impact of device design on the electronic and optoelectronic properties of integrated Ru-terpyridine complexes

• Max Mennicken,
• Sophia Katharina Peter,
• Corinna Kaulen,
• Ulrich Simon and
• Silvia Karthäuser

Beilstein J. Nanotechnol. 2022, 13, 219–229, doi:10.3762/bjnano.13.16

• makes them superior candidates for charge transport studies and functional nanodevices [16][17][18]. Using TP-based ligands and a reactive Ru precursor, we recently succeeded to establish a room-temperature method to grow Ru-TP supramolecular wires by sequential reaction [19]. The stepwise wire growth

• needs a minimum energy of about 500 meV (Figure 6a), which is sufficient to initiate charge transport to the electrodes. Raising USD over this threshold voltage leads to a further increase in current. Consequently, we assume, that in Ru(MPTP)2–AuNP devices a plasmon-induced metal-to-ligand charge

Measurement of polarization effects in dual-phase ceria-based oxygen permeation membranes using Kelvin probe force microscopy

• Kerstin Neuhaus,
• Christina Schmidt,
• Liudmila Fischer,
• Wilhelm Albert Meulenberg,
• Ke Ran,
• Joachim Mayer and
• Stefan Baumann

Beilstein J. Nanotechnol. 2021, 12, 1380–1391, doi:10.3762/bjnano.12.102

• expected to be in the spinel region rather than on another site of the ceria phase. Another possible explanation would be that enhanced charge transport by electrons occurs along the grain boundary. This has already been confirmed experimentally for similar composite materials [33]. In this case, an

• the sign of the polarization, it was observed in some cases that charge is obviously distributed along scratches on the surface, which were introduced by polishing. This underlines the hypothesis, that fast charge transport in ceria-based materials via the uppermost surface layers is still possible at

• very low temperatures, while the charge transport in the bulk of the material is strongly reduced compared to “usual” operation temperatures (600–900 °C), due to freezing of the oxygen vacancies and formation of defect accumulates [32]. At the same time, the direct polarization effect was confined to

Morphology-driven gas sensing by fabricated fractals: A review

• Vishal Kamathe and
• Rupali Nagar

Beilstein J. Nanotechnol. 2021, 12, 1187–1208, doi:10.3762/bjnano.12.88

• sensitization mechanisms [26]. The mechanisms focusing on a macroscopic perspective deal with adsorption/desorption of surface atomic/molecular species or discuss how the bulk resistance and gas diffusion control mechanisms affect the charge transport [26][87][89]. The changes in electrical resistance of the

• this could be due to grain boundary resistance, which controls the charge transport and thereby nullifies the effect of fractal morphology. Further, the possibility of gas molecules to diffuse in the material via surface diffusion, Knudsen diffusion (radius of pores in the range of 1–100 nm) and

• reaction canals, and centers for adsorptions [57][69]. For larger pore sizes, rapid gas diffusion rates are observed leading to higher values of sensitivity [26][89]. Thus, while the porous continuous network provides a backbone for better and faster charge transport, the unique morphology of fab-fracs

Assessment of the optical and electrical properties of light-emitting diodes containing carbon-based nanostructures and plasmonic nanoparticles: a review

• Keshav Nagpal,
• Erwan Rauwel,
• Frédérique Ducroquet and
• Protima Rauwel

Beilstein J. Nanotechnol. 2021, 12, 1078–1092, doi:10.3762/bjnano.12.80

• doping-free and cost-effective, it can be operated using a single bias, and it emanates a narrow EL spectrum of ≈30 meV. Similarly, white light LED can also consist of CQD at the EML along with metal oxides in the charge transport layers [94]. In addition, a maximum EQE of 0.083% has been obtained from

Molecular assemblies on surfaces: towards physical and electronic decoupling of organic molecules

• Sabine Maier and
• Meike Stöhr

Beilstein J. Nanotechnol. 2021, 12, 950–956, doi:10.3762/bjnano.12.71

• these ultrathin interfacial layers significantly reduce both the molecular adsorption energy and the hybridization of molecular states with the electronic bands in metals and semiconductors. However, charge transport is not completely inhibited, and electrons can still tunnel from the metal through

Nanoporous and nonporous conjugated donor–acceptor polymer semiconductors for photocatalytic hydrogen production

• Zhao-Qi Sheng,
• Yu-Qin Xing,
• Yan Chen,
• Guang Zhang,
• Shi-Yong Liu and
• Long Chen

Beilstein J. Nanotechnol. 2021, 12, 607–623, doi:10.3762/bjnano.12.50

• units, among which the pyrene–pyrimidine-based P32 (Figure 4) with the lowest nitrogen content showed the highest HER. Nitrogen heterocycles within polymers could optimize wettability, bandgap, charge transport, and separation. Motivated by the planar configuration and strong electron-acceptor

• -assembling pristine polymers (P52 and P53) and hydrophilic PEG45-b-PMMA103 (Figure 5). The hyperbranched Pdots yielded higher HERs (as high as 16.8 μmol·h−1 (20 mg) for P53) than the linear Pdot P52, due to the shortened charge transport pathway, 3D transport, and more negative reduction potentials of the

Boosting of photocatalytic hydrogen evolution via chlorine doping of polymeric carbon nitride

• Malgorzata Aleksandrzak,
• Michalina Kijaczko,
• Wojciech Kukulka,
• Daria Baranowska,
• Martyna Baca,
• Beata Zielinska and
• Ewa Mijowska

Beilstein J. Nanotechnol. 2021, 12, 473–484, doi:10.3762/bjnano.12.38

• pairs, (iv) improved photogenerated charge transport and separation, and (v) higher reducing ability of the photogenerated electrons. The above factors affected the 4.4-fold enhancement of the photocatalytic efficiency in hydrogen evolution in comparison to the pristine catalyst. Keywords: chlorine

• hydrogen evolution reaction from water compared to pristine PCN. The investigation showed that the enhanced photocatalytic activity was attributed to an improved photogenerated charge transport and separation. Here, chlorine atoms could act as a charge carrier transport bridge between the carbon nitride

• planes, (ii) a non-reduction in the bandgap energy, (iii) a lower recombination rate of the electron–hole pairs, (iv) improved photogenerated charge transport and separation, and (v) an enhanced reducing ability of the photogenerated electrons. Therefore, it is believed that heteroatom doping of pristine

Kondo effects in small-bandgap carbon nanotube quantum dots

• Patryk Florków,
• Damian Krychowski and
• Stanisław Lipiński

Beilstein J. Nanotechnol. 2020, 11, 1873–1890, doi:10.3762/bjnano.11.169

• nanoscopic system. The storage capacity of three-state or four-state qudits is obviously higher than the capacity of a qubit. In the present paper, we are interested in transport properties. The regime of charge transport depends on the ratio between tunnel-induced broadening of dot energy levels and

Unravelling the interfacial interaction in mesoporous SiO₂@nickel phyllosilicate/TiO₂ core–shell nanostructures for photocatalytic activity

• Bridget K. Mutuma,
• Xiluva Mathebula,
• Isaac Nongwe,
• Bonakele P. Mtolo,
• Boitumelo J. Matsoso,
• Rudolph Erasmus,
• Zikhona Tetana and
• Neil J. Coville

Beilstein J. Nanotechnol. 2020, 11, 1834–1846, doi:10.3762/bjnano.11.165

• recombination, leading to faster charge transport and photodegradation. Typically, the photocatalytic degradation efficacy of TiO2 depends on the surface area and metal-ion doping on the surface. Metal-ion doping of TiO2 influences its interfacial charge-transfer properties [51]. Differences in

Effect of localized helium ion irradiation on the performance of synthetic monolayer MoS₂ field-effect transistors

• Jakub Jadwiszczak,
• Pierce Maguire,
• Conor P. Cullen,
• Georg S. Duesberg and
• Hongzhou Zhang

Beilstein J. Nanotechnol. 2020, 11, 1329–1335, doi:10.3762/bjnano.11.117

• , we find that irradiating the electrode–channel interface has a deleterious impact on charge transport when contrasted with irradiations confined only to the transistor channel. Keywords: 2D materials; contacts; defect engineering; helium ion microscope; ion beam doping; vacancies; two-dimensional

• creation of defects in TMD FETs may serve to improve charge transport and tune the device performance [10][20][28], while the effective donor concentration and the introduced scattering potentials need to be tailored accordingly [29][30]. Thus far, these studies have focused either on spatially confined

• repeatedly by adjacent line scans, increasing the effective delivered dose and shifting that region to a more acceptor-rich area. This leads to the observed ambipolar gate response for large IR values. The formation of these back-to-back heterojunctions may result in unconventional charge transport phenomena

Templating effect of single-layer graphene supported by an insulating substrate on the molecular orientation of lead phthalocyanine

• K. Priya Madhuri,
• Abhay A. Sagade,
• Pralay K. Santra and
• Neena S. John

Beilstein J. Nanotechnol. 2020, 11, 814–820, doi:10.3762/bjnano.11.66

• monoclinic moieties along the qz direction indicates that the PbPc molecules exhibit ordered stacking, normal to the substrate plane. This type of vertical ordering known as cofacial arrangement can promote charge transport in the vertical direction [6][9][26]. Further, a small fraction of the (320

• ). The conducting domains may arise as a result of face-on monoclinic fractions that are vertically stacked. Such stacked molecules can give rise to more energy states near the bandgap aiding charge transport [9]. The less conductive regions may have triclinic moieties or other crystallite arrangements

• that do not facilitate charge transport. Figure 6d is the I–V curve acquired from one of the conducting domains in the vertical configuration. The curve is non-linear as expected for PbPc and higher current values are observed. The obtained I–V plot can be fitted to a generalized Simmons equation

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

• ][10], and metals [11][12][13]. C-AFM has been used to characterize local charge transport characteristics [4][6] and to obtain detailed information about local charge mobility [5][7]. However, contact-mode AFM techniques, where the probe continuously interacts with the surface in a repulsive manner

Recent progress in perovskite solar cells: the perovskite layer

• Xianfeng Dai,
• Ke Xu and
• Fanan Wei

Beilstein J. Nanotechnol. 2020, 11, 51–60, doi:10.3762/bjnano.11.5

• can effectively improve the charge transport efficiency by eliminating the defect and trap density in the perovskite film. The resulting planar PSCs doped with 5 mol % FAAc achieved a PCE of 18.90%, which corresponds to an enhancement of the PCE of over 20% compared to those fabricated by doping with

Mobility of charge carriers in self-assembled monolayers

• Zhihua Fu,
• Tatjana Ladnorg,
• Hartmut Gliemann,
• Alexander Welle,
• Asif Bashir,
• Michael Rohwerder,
• Qiang Zhang,
• Björn Schüpbach,
• Andreas Terfort and
• Christof Wöll

Beilstein J. Nanotechnol. 2019, 10, 2449–2458, doi:10.3762/bjnano.10.235

• study charge transport within 2D layers of organic semi-conductors (OSCs) using atomic force microscopy (AFM)-based lithography applied to self-assembled monolayers (SAMs), fabricated from appropriate organothiols. The extent of lateral charge transport was investigated by insulating pre-defined patches

• a top electrode. We were able to determine a relationship between island size and electrical conductivity, and from this dependence, we could obtain information on the lateral charge transport and charge carrier mobility within the thin OSC layers. Our study demonstrates that AFM nanografting of

• the determination of mobilities in macroscopic samples. Keywords: conducting atomic force microscopy; lateral charge transport; nanografting; organic semiconductor; self-assembled monolayer; Introduction Charge transport in organic semiconductors plays a central role in the field of molecular

Nontoxic pyrite iron sulfide nanocrystals as second electron acceptor in PTB7:PC₇₁BM-based organic photovoltaic cells

• Olivia Amargós-Reyes,
• José-Luis Maldonado,
• Omar Martínez-Alvarez,
• María-Elena Nicho,
• José Santos-Cruz,
• Juan Nicasio-Collazo,
• Irving Caballero-Quintana and
• Concepción Arenas-Arrocena

Beilstein J. Nanotechnol. 2019, 10, 2238–2250, doi:10.3762/bjnano.10.216

• OPV active layer, the harvesting solar energy is usually enhanced as well as the charge transport and the charge collection behavior at the electrodes, and in some cases, also the lifetime stability is increased. However, such effects depend on the type of the third compound and its concentration in

• reference device with a PCE of 2.32%. Hence, FeS2 NCs have widely been used to enhance the efficiency of solar cells by improving dissociation and charge transport. In our previous work [48], we reported the noncytotoxicity of cube-like FeS2 NCs by studying mouse fibroblast cells at different reaction

• characteristics could facilitate exciton dissociation, charge transport and collection processes, and thus increase the overall PCE value. Figure 5a shows the UV–vis absorption spectra of the OPV active layer at different concentrations of FeS2 as well as that of the pure FeS2 film. The spectrum of the PTB7

Prestress-loading effect on the current–voltage characteristics of a piezoelectric p–n junction together with the corresponding mechanical tuning laws

• Wanli Yang,
• Shuaiqi Fan,
• Yuxing Liang and
• Yuantai Hu

Beilstein J. Nanotechnol. 2019, 10, 1833–1843, doi:10.3762/bjnano.10.178

• ][7][8][9][10][11][12][13], MOSFETs [1][14], and acoustic charge transport devices [15][16][17]. For piezoelectric semiconductor devices, analyses on the static, time-harmonic and transient behaviors seem particularly important regarding their applications and development [18]. Zhang et al. [19