Cyclodextrin inhibits zinc corrosion by destabilizing point defect formation in the oxide layer

• Abdulrahman Altin,
• Maciej Krzywiecki,
• Adnan Sarfraz,
• Cigdem Toparli,
• Claudius Laska,
• Philipp Kerger,
• Aleksandar Zeradjanin,
• Karl J. J. Mayrhofer,
• Michael Rohwerder and
• Andreas Erbe

Beilstein J. Nanotechnol. 2018, 9, 936–944, doi:10.3762/bjnano.9.86

• reactions, forming precipitates such as hydrated zinc oxide [15]. ZnO is naturally an n-type semiconductor with a band gap of 3.4 eV [20]. Oxides formed in an aerated corrosion process are typically defect-rich oxides [21], especially in the presence of Cl− [15]. Consequently, the products remain initially

• − HOMO-CDonset to be 1.85 eV. The band gap of β-CD has been reported to be 12.44 eV [38], and judging from the position of the Fermi level, β-CD is in the same role as a p-type system. Charge dislocation must lead to hole accumulation at the ZnO side, i.e., depletion of negative charge. On the β-CD side

Comparative study of antibacterial properties of polystyrene films with TiO_x and Cu nanoparticles fabricated using cluster beam technique

• Vladimir N. Popok,
• Cesarino M. Jeppesen,
• Peter Fojan,
• Anna Kuzminova,
• Jan Hanuš and
• Ondřej Kylián

Beilstein J. Nanotechnol. 2018, 9, 861–869, doi:10.3762/bjnano.9.80

• ], and they are also cheaper compared to silver. These particles mainly show bactericidal effects through mechanisms (i) and (iii). Among the metal oxides, TiO2 is the best-known and most widely used semiconductor material with a wide band gap that under UV illumination generates electron–hole pairs

Noble metal-modified titania with visible-light activity for the decomposition of microorganisms

• Maya Endo,
• Zhishun Wei,
• Kunlei Wang,
• Baris Karabiyik,
• Kenta Yoshiiri,
• Paulina Rokicka,
• Bunsho Ohtani,
• Agata Markowska-Szczupak and
• Ewa Kowalska

Beilstein J. Nanotechnol. 2018, 9, 829–841, doi:10.3762/bjnano.9.77

• wide band gap of titania of 3.0–3.2 eV and the recombination of charge carriers). There are various ways to improve photocatalytic performance of titania photocatalysts: (1) to inhibit the recombination of charge carriers, and (2) to extend its working abilities to the visible-light region, for example

• and in some cases, bare titania shows larger photocatalytic activity [45]. It should be reminded that the titania samples here are commercial samples, and thus with small content of impurities and defects, which can increase the visible-light activity of titania by narrowing of the band gap. The

Facile synthesis of a ZnO–BiOI p–n nano-heterojunction with excellent visible-light photocatalytic activity

• Mengyuan Zhang,
• Jiaqian Qin,
• Pengfei Yu,
• Bing Zhang,
• Mingzhen Ma,
• Xinyu Zhang and
• Riping Liu

Beilstein J. Nanotechnol. 2018, 9, 789–800, doi:10.3762/bjnano.9.72

• poor utilization of visible light, which accounts for 45% of the solar radiation spectrum, because of their wide band gap. Some effort must be paid to extend their working spectrum efficiently. As is known to all, it is metal orbitals which contribute to the conduction band (CB) of the metal-containing

• semiconductor’s band gap. Bismuth(III)-containing semiconductors (such as bismuth oxide [17], bismuth vanadate [18][19], bismuth tungstate [20], bismuth perovskite [21], bismuth molybdate [22], etc.) have been extensively researched as a broad hybrid orbital composed of Bi 6s in the field of photocatalysis

• . Recently, bismuth oxyhalides have been proposed as a new kind of narrow band gap p-type semiconductor photocatalyst material whose general formula is BiOX, where X represents Cl, Br or I. They crystallize in the tetragonal matlockite structure with space group P4/NMMS. In the crystal structure of all these

Surface-plasmon-enhanced ultraviolet emission of Au-decorated ZnO structures for gas sensing and photocatalytic devices

• T. Anh Thu Do,
• Truong Giang Ho,
• Thu Hoai Bui,
• Quang Ngan Pham,
• Hong Thai Giang,
• Thi Thu Do,
• Duc Van Nguyen and
• Dai Lam Tran

Beilstein J. Nanotechnol. 2018, 9, 771–779, doi:10.3762/bjnano.9.70

• target gases [14][15][16]. In another research strategy to obtain high photocatalytic performance materials, ZnO, a wide-band gap semiconductor (Eg > 3 eV), can also be used as a suitable material for photocatalysts based on the particular plasmonic characteristics of the nanostructures. Herein, it was

• the band gap of the ZnO particles slightly decreases when decorated with the Au NPs. Photoluminescence measurements of ZnO and Au NP/ZnO samples were performed at room temperature, as shown in Figure 3c. The PL spectra exhibit an intense, narrow UV band edge emission at 385 nm, and a defect-related

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

• values for the electrochemical energy band gap (Eg). The electrochemical properties of pure SP1 and SP2 in solution were examined. The behavior of both compounds during reduction and oxidation processes were investigated in order to determine the energy levels and band gaps. For SP1 imine, the peak

Perovskite-structured CaTiO₃ coupled with g-C₃N₄ as a heterojunction photocatalyst for organic pollutant degradation

• Ashish Kumar,
• Christian Schuerings,
• Suneel Kumar,
• Ajay Kumar and
• Venkata Krishnan

Beilstein J. Nanotechnol. 2018, 9, 671–685, doi:10.3762/bjnano.9.62

• of a wide band gap material with a low band gap material [30]. Natarajan et al. have demonstrated the enhanced degradation of isoniazid (a pharmaceutical pollutant) over the g-C3N4–TiO2 nanocomposite via a direct Z-scheme charge transfer mechanism [31]. The enhanced photocatalytic activity has been

• between g-C3N4 and SrTiO3 [34]. Thus, wide band gap materials can play an important role in maximizing the photocatalytic activity of g-C3N4 by suppressing the photogenerated charge recombination. CaTiO3 (CT) is a well-known titanium-based perovskite material with a wide band gap of ≈3.5 eV and its

• methylene blue (MB) and thiabendazole (TBZ) under visible light irradiation. Another attractive strategy for enhancement of photocatalytic performance is the coupling of a wide band gap material with a low band gap material, which allows the charge transfer via suitably arranged band edge positions in both

Mechanistic insights into plasmonic photocatalysts in utilizing visible light

• Kah Hon Leong,
• Azrina Abd Aziz,
• Lan Ching Sim,
• Pichiah Saravanan,
• Min Jang and
• Detlef Bahnemann

Beilstein J. Nanotechnol. 2018, 9, 628–648, doi:10.3762/bjnano.9.59

• which has a distinctive electronic configuration structure (filled valence band and an empty conduction band). When exposed to direct sunlight irradiation, the UV light breaks the band gap energy of TiO2 (3.2 eV) and then activates the electrons in the valence band. Thus, activated electrons move to the

Sensing behavior of flower-shaped MoS₂ nanoflakes: case study with methanol and xylene

• Maryam Barzegar,
• Masoud Berahman and
• Azam Iraji zad

Beilstein J. Nanotechnol. 2018, 9, 608–615, doi:10.3762/bjnano.9.57

• emerging new group of materials known as transition metal dichalcogenides (TMDs), which have significant electrical, optical, and transport properties. MoS2 is one of the well-known 2D materials in this group, which is a semiconductor with controllable band gap based on its structure. The hydrothermal

• a large surface-to-volume ratio, high process compatibility and flexibility, make them good candidates for sensing applications [8][14][15]. One of the most explored materials in this group is MoS2, which is a semiconductor with a variable band gap based on the number of layers [14][15]. Numerous

• nanoflakes. There are numbers of articles which report the successful growth of flower-like MoS2 nanoflakes using this technique [19][20][21][22][23]. Due to the high surface-to-volume ratio, activity, tunable band gap, low electrical noise and acceptable electrical conductivity, MoS2 is considered as one of

Fabrication and photoactivity of ionic liquid–TiO₂ structures for efficient visible-light-induced photocatalytic decomposition of organic pollutants in aqueous phase

• Anna Gołąbiewska,
• Marta Paszkiewicz-Gawron,
• Aleksandra Sadzińska,
• Wojciech Lisowski,
• Ewelina Grabowska,
• Adriana Zaleska-Medynska and
• Justyna Łuczak

Beilstein J. Nanotechnol. 2018, 9, 580–590, doi:10.3762/bjnano.9.54

• , low cost, nontoxicity and availability [5]. Despite many advantages, the commercial application of TiO2 to solve environmental problems is still limited. The main obstacle is the relatively wide band gap of 3.2 eV for anatase that limits the photoexcitation wavelength needed to activate photocatalytic

• proposed to be due to: (i) doping of nonmetal elements (e.g., N, B, F) derived from the IL structure, inducing a narrower band gap and improving the separation efficiency of the photogenerated electron/hole pairs [13][36][37]; (ii) enhancement of Ti3+ species formation in the TiO2 lattice (being a source

Revealing the interference effect of Majorana fermions in a topological Josephson junction

• Jie Liu,
• Tiantian Yu and
• Juntao Song

Beilstein J. Nanotechnol. 2018, 9, 520–529, doi:10.3762/bjnano.9.50

• will not destroy the parity of the Andreev bound states. When the wire length is finite (e.g., L1 = L2 = 100a), we can see from the dashed line that a band gap δEM exists at = π. Thus, the parity is destroyed, and the Josephson current has a 2π period. There is no 4π fractional Josephson Effect in the

Influence of the preparation method on the photocatalytic activity of Nd-modified TiO₂

• Patrycja Parnicka,
• Paweł Mazierski,
• Tomasz Grzyb,
• Wojciech Lisowski,
• Ewa Kowalska,
• Bunsho Ohtani,
• Adriana Zaleska-Medynska and
• Joanna Nadolna

Beilstein J. Nanotechnol. 2018, 9, 447–459, doi:10.3762/bjnano.9.43

• to its possible applications in the treatment of air, water and wastewater [1][2][3][4][5] after the photocatalytic splitting of water on TiO2 electrodes was discovered by Fujishima and Honda in 1972 [6]. However, serious disadvantages of TiO2 are its wide band gap, which requires the use of

• ultraviolet light irradiation for excitation (the band gap of anatase is about 3.2 eV) and low quantum yield (due to the fast recombination of electron–hole pairs) [7]. These restrictions on its application could be overcome by modifying TiO2, which results in increased activity and ability to work under

• energy level in the band gap and charge transfer between the TiO2 valence band and Nd3+ ion levels [36]. Furthermore, there are four absorption bands in the vis region typical for neodymium located at 520, 585, 745 and 805 nm. They correspond to transitions from the 4I9/2 ground state to the excited

Facile synthesis of ZnFe₂O₄ photocatalysts for decolourization of organic dyes under solar irradiation

• Arjun Behera,
• Debasmita Kandi,
• Sanjit Manohar Majhi,
• Satyabadi Martha and
• Kulamani Parida

Beilstein J. Nanotechnol. 2018, 9, 436–446, doi:10.3762/bjnano.9.42

• the scientific community. To exploit solar light more efficiently, photocatalysts with narrow band gap (e.g., ZnSnO3 [2], Bi2WO6 [3], Ce(MoO4)2 [4] and ZnFe2O4 [5]) have been used, for absorbance of solar light in the visible region. Among ternary metal oxides, transition metal ferrites have drawn a

• magnetic in nature [10][11][12][13]. Among different metal ferrite materials, zinc ferrite (ZnFe2O4) plays a significant role because of its low band gap (1.88 eV), high thermal conductivity, good chemical stability, higher specific strength, magneto-resistive and magneto optical properties and low

• fabrication cost [14]. ZnFe2O4 is an n-type semiconductor having a direct band gap with suitable band edge positions for various photocatalytic processes. It is a solid solution of ferric oxide and zinc oxide, which greatly enhances the charge carrier separation. To date, various methods such as refluxing

Temperature-tunable lasing from dye-doped chiral microdroplets encapsulated in a thin polymeric film

• Gia Petriashvili,
• Mauro Daniel Luigi Bruno,
• Maria Penelope De Santo and
• Riccardo Barberi

Beilstein J. Nanotechnol. 2018, 9, 379–383, doi:10.3762/bjnano.9.37

• )/2, where ne and no are the extraordinary and ordinary refraction indices, respectively. As a consequence, a whole range of wavelengths does not propagate inside the material and it is indicated as photonic band gap (PBG). The full width at half maximum of the PBG equals to Δλ = pΔn, where Δn = ne

Sugarcane juice derived carbon dot–graphitic carbon nitride composites for bisphenol A degradation under sunlight irradiation

• Lan Ching Sim,
• Jing Lin Wong,
• Chen Hong Hak,
• Jun Yan Tai,
• Kah Hon Leong and
• Pichiah Saravanan

Beilstein J. Nanotechnol. 2018, 9, 353–363, doi:10.3762/bjnano.9.35

• semiconductor g-C3N4 possesses visible light harvesting properties due to its narrow band gap energy (≈2.7 eV) [15]. Thus g-C3N4 has emerged as a promising polymeric semiconductor for photocatalytic reduction of carbon dioxide (CO2) [16][17][18][19][20], hydrogen evolution [21][22][23][24][25], oxidation of NO

• onset of the absorption spectra of pure g-C3N4 started from 452 nm, showing a band gap of 2.75 eV, which is almost the same as that previously reported [28][46][64]. It is obvious that all CD/g-C3N4 composites displayed a broad light absorption in the whole solar spectrum ranging from 200 to 800 nm due

• semiconductor at the point of zero charge was estimated using the following equations: where EVB and ECB are the VB and CB edge potential respectively, X is the electronegativity of the semiconductor; Ec is the energy of free electrons on the hydrogen scale (≈4.5 eV vs NHE) and Eg is the band gap energy of the

BN/Ag hybrid nanomaterials with petal-like surfaces as catalysts and antibacterial agents

• Konstantin L. Firestein,
• Denis V. Leybo,
• Alexander E. Steinman,
• Andrey M. Kovalskii,
• Andrei T. Matveev,
• Anton M. Manakhov,
• Irina V. Sukhorukova,
• Pavel V. Slukin,
• Nadezda K. Fursova,
• Sergey G. Ignatov,
• Dmitri V. Golberg and
• Dmitry V. Shtansky

Beilstein J. Nanotechnol. 2018, 9, 250–261, doi:10.3762/bjnano.9.27

• nanostructures opens up new opportunities to improve the performance of hybrid nanomaterials. Many techniques for surface modification [4] and band-gap engineering [41][42] were described in the past few years. This allows for a control of size and homogeneity of Ag NPs, adhesion and charge distribution on the

Anchoring of a dye precursor on NiO(001) studied by non-contact atomic force microscopy

• Sara Freund,
• Antoine Hinaut,
• Nathalie Marinakis,
• Edwin C. Constable,
• Ernst Meyer,
• Catherine E. Housecroft and
• Thilo Glatzel

Beilstein J. Nanotechnol. 2018, 9, 242–249, doi:10.3762/bjnano.9.26

• photovoltaics such as dye-sensitized solar cells (DSSCs) [1][2][3][4]. In the latter field, the wide band gap n-type semiconductor TiO2 has become one of the most common metal oxides for the design of classical n-type DSSCs, and is therefore a widely studied material, in particular in the field of scanning

• fundamental studies including those at the molecular or sub-molecular scale [6][7][8][9][10][11][12][13][14]. In contrast, the synthesis and characterization of p-type wide band gap metal oxide materials and especially the fabrication and analysis of p-type DSSCs with a photoactive cathode, are less commonly

• discussed [15][16]. Such p-type DSSCs are a first step towards the fabrication of hybrid tandem solar cells where both electrodes will be photoactive allowing for higher open-circuit voltages and energy conversion efficiencies [15][17]. The first reported p-type wide band gap metal oxide material was NiO

Bombyx mori silk/titania/gold hybrid materials for photocatalytic water splitting: combining renewable raw materials with clean fuels

• Stefanie Krüger,
• Michael Schwarze,
• Otto Baumann,
• Christina Günter,
• Michael Bruns,
• Christian Kübel,
• Dorothée Vinga Szabó,
• Rafael Meinusch,
• Verónica de Zea Bermudez and
• Andreas Taubert

Beilstein J. Nanotechnol. 2018, 9, 187–204, doi:10.3762/bjnano.9.21

• here is photocatalytic water splitting, the bandgap is important. It was determined via solid state UV–vis reflection spectroscopy via Kubelka–Munk analysis [61]. The indirect bandgap for all materials is 3.15 ± 0.10 eV, regardless of the presence or absence of Au. This band gap is slightly lower than

• materials are mainly anatase with a bandgap of 3.15 eV; presumably this slightly larger band gap results is a somewhat less effective use of the irradiated light compared to the example by Matsuoka. As a result, there are differences between these materials making a quantitative comparison between the

A robust AFM-based method for locally measuring the elasticity of samples

• Alexandre Bubendorf,
• Stefan Walheim,
• Thomas Schimmel and
• Ernst Meyer

Beilstein J. Nanotechnol. 2018, 9, 1–10, doi:10.3762/bjnano.9.1

• ]. In physics, the band gap size of nanocrystals and the presence of planar defects on nanotubes are a function of the Young’s modulus [2][3]. Probing local elasticity requires an instrumentation capable of operating with high resolution and under different conditions, such as variable temperature

Inelastic electron tunneling spectroscopy of difurylethene-based photochromic single-molecule junctions

• Youngsang Kim,
• Safa G. Bahoosh,
• Dmytro Sysoiev,
• Thomas Huhn,
• Fabian Pauly and
• Elke Scheer

Beilstein J. Nanotechnol. 2017, 8, 2606–2614, doi:10.3762/bjnano.8.261

• . Although the DFT+Σ method applied here is supposed to reduce level-alignment and band-gap errors, they might not be completely lifted in the closed form. Another important uncertainty, this time on the experimental side, stems from the interpretation of particular peaks in the conductance histograms. We

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

• of CsPbI3 QDs in the temperature range of 90–170 °C via the PTEF-based microreactor system since the growth of QDs involves the migration/diffusion of atoms/ions. In comparison with the CsPbBr3 QDs, the PL spectra of the CsPbI3 QDs is much wider, suggesting that the CsPbI3 QDs have a smaller band gap

• . The red shift shown in Figure 5 suggests that the band gap of the prepared QDs is temperature dependent, which is similar to the behavior of IV, III–V, and II–VI semiconductors. According to the Varshni empirical relationship, Egap(T) = Egap(0) − αT2/(β + T) [38], (Egap(0) is the band gap at 0 K, α is

• the coefficient of thermal expansion, and β is the Debye temperature), increasing temperature leads to the decease of the band gap. This phenomenon makes it easy for the charge carriers (electrons and/or holes) to be activated and to move to a low energy state in comparison with the charge carriers at

Optical contrast and refractive index of natural van der Waals heterostructure nanosheets of franckeite

• Patricia Gant,
• Foad Ghasemi,
• David Maeso,
• Carmen Munuera,
• Elena López-Elvira,
• Riccardo Frisenda,
• David Pérez De Lara,
• Gabino Rubio-Bollinger,
• Mar Garcia-Hernandez and
• Andres Castellanos-Gomez

Beilstein J. Nanotechnol. 2017, 8, 2357–2362, doi:10.3762/bjnano.8.235

• that franckeite is a semiconductor with narrow band gap. Other 2D semiconductors, such as MoS2, present refractive indexes whose imaginary part vanishes within the visible region of the spectrum. Moreover, the refractive index of transition-metal dichalcogenides shows sharp features associated to 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

• of the efficiency of energy transfer between confined NC layers. An exponential decrease of the ACS with decreasing temperature down to 120 K can be explained by smaller occupation number of phonons and expansion of the band gap of Si NCs at low temperatures. This study clearly shows that the ACS of

• -assisted transitions the occupation number of phonons is an exponential function [1] of temperature containing the Bose–Einstein statistical factor: where Ωph is the typical (average) phonon energy and kB is the Boltzmann constant. Second, with varying temperatures the band gap of a NC is shifting. This

• changes the effective DOS at a certain energy. Following the phenomenological expression proposed by Cardona’s group [30] we can write: where B is a temperature-independent constant related to the strength of the electron–phonon interaction, and Egap,0 corresponds to the band gap at 0 K. The ACS is equal

Hydrothermal synthesis of ZnO quantum dot/KNb₃O₈ nanosheet photocatalysts for reducing carbon dioxide to methanol

• Xiao Shao,
• Weiyue Xin and
• Xiaohong Yin

Beilstein J. Nanotechnol. 2017, 8, 2264–2270, doi:10.3762/bjnano.8.226

• reflectance spectra for different amounts of ZnO quantum dots loaded onto KNb3O8 nanosheets are illustrated in Figure 7. The steep absorption edge of the pure KNb3O8 nanosheets occurred around 343 nm under UV light owing to its large intrinsic band gap. When increasing the ZnO quantum dot loading, the sample

• displayed an absorption threshold at 376 nm. Compared with the pure KNb3O8 nanosheets, we found a significant red-shift of the absorption edge, which could attribute to the enhancement observed by the ZnO quantum dots upon visible-light absorption. The optical band gap (Eg) of semiconductors could be

• electrode potential (4.5 eV) and Eg is the band gap energy. The results indicated that the conduction band of pure ZnO quantum dots (ECB = −1.02 V vs NHE at pH 7, the same below) [25][28] and pure KNb3O8 nanosheets (ECB = −0.94V) are more negative than the position of the reduction of CO2 to methanol (ECO2

High-stress study of bioinspired multifunctional PEDOT:PSS/nanoclay nanocomposites using AFM, SEM and numerical simulation

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

Beilstein J. Nanotechnol. 2017, 8, 2069–2082, doi:10.3762/bjnano.8.207

• studies have investigated the relationship between applied stress and movement of the embedded hard particles [26]. When periodicity of inclusions is obtained in the nanocomposite, tunability of the photonic [27] or phononic [28] band gap has been achieved by applying mechanical stress. In this paper, we