Hierarchical Bi₂WO₆/TiO₂-nanotube composites derived from natural cellulose for visible-light photocatalytic treatment of pollutants

• Zehao Lin,
• Zhan Yang and
• Jianguo Huang

Beilstein J. Nanotechnol. 2022, 13, 745–762, doi:10.3762/bjnano.13.66

• the uniform anchoring of Bi2WO6 nanoparticles on TiO2 nanotubes, as well as strong mutual effects and well-proportioned formation of heterostructures in between the Bi2WO6 and TiO2 phases. These improvements arose from the cellulose-derived unique structures, leading to an enhanced absorption of

• ][8]. However, the wide bandgap of TiO2 inhibits the absorption of light in the visible region and the rapid recombination of photogenerated electron−hole pairs restrains its photocatalytic activity. It has been verified that constructing TiO2-based heterostructured composites by using visible-light

• TiO2-NT, and pure Bi2WO6 powder samples, where all present two similar absorption bands at 1625 and 3420 cm−1 which can be indexed to the stretching vibration of adsorbed H2O and –OH group on the sample surface [37]. Apart from the 30%−Bi2WO6/TiO2-NT nanocomposite, the FTIR spectra of the other Bi2WO6

A nonenzymatic reduced graphene oxide-based nanosensor for parathion

• Sarani Sen,
• Anurag Roy,
• Ambarish Sanyal and
• Parukuttyamma Sujatha Devi

Beilstein J. Nanotechnol. 2022, 13, 730–744, doi:10.3762/bjnano.13.65

• performance of the nanosensor was validated by adding PT to natural samples and comparing the data via absorption spectroscopy. PT detection results encourage the design of easy-to-use nanosensor-based analytical tools for rapidly monitoring other environmental samples. Keywords: electrochemical nanosensor

• (mass, absorption, fluorescence) techniques are time-consuming, laborious, costy, require specific and sophisticated instruments and trained personnel, and most often are not portable to enable on-site detection [5][6]. Electrochemical nanosensors are one of the preferred methodologies due of their fast

• PT was tested five times, and the average value was represented with standard deviation. The results also validate the standard spectrophotometric analysis. Quantification of parathion using spectrophotometry The ultraviolet–visible (UV–vis) absorption spectroscopic study was performed to validate

Tunable high-quality-factor absorption in a graphene monolayer based on quasi-bound states in the continuum

• Jun Wu,
• Yasong Sun,
• Feng Wu,
• Biyuan Wu and
• Xiaohu Wu

Beilstein J. Nanotechnol. 2022, 13, 675–681, doi:10.3762/bjnano.13.59

• /bjnano.13.59 Abstract A tunable graphene absorber, composed of a graphene monolayer and a substrate spaced by a subwavelength dielectric grating, is proposed and investigated. Strong light absorption in the graphene monolayer is achieved due to the formation of embedded optical quasi-bound states in the

• continuum in the subwavelength dielectric grating. The physical origin of the absorption with high quality factor is examined by investigating the electromagnetic field distributions. Interestingly, we found that the proposed absorber possesses high spatial directivity and performs similar to an antenna

• , which can also be utilized as a thermal emitter. Besides, the spectral position of the absorption peak can not only be adjusted by changing the geometrical parameters of dielectric grating, but it is also tunable by a small change in the Fermi level of the graphene sheet. This novel scheme to tune the

Reliable fabrication of transparent conducting films by cascade centrifugation and Langmuir–Blodgett deposition of electrochemically exfoliated graphene

• Teodora Vićentić,
• Stevan Andrić,
• Vladimir Rajić and
• Marko Spasenović

Beilstein J. Nanotechnol. 2022, 13, 666–674, doi:10.3762/bjnano.13.58

• wavelength of 660 nm and the number of graphene layers was calculated for each sample, taking into account an absorption of 2.3% for each layer of graphene, as in the work by Bonaccorso and co-workers [43]. Although atomic force microscopy (AFM) is often employed to characterize graphene films [2][12][14][44

Antibacterial activity of a berberine nanoformulation

• Hue Thi Nguyen,
• Tuyet Nhung Pham,
• Anh-Tuan Le,
• Nguyen Thanh Thuy,
• Tran Quang Huy and
• Thuy Thi Thu Nguyen

Beilstein J. Nanotechnol. 2022, 13, 641–652, doi:10.3762/bjnano.13.56

• the preparation of berberine (BBR) in nanoformulation to enhance its solubility and increase its antibacterial effectiveness against hospital-acquired infections. BBR nanoparticles (BBR NPs) were formed by antisolvent precipitation (ASP) using glycerol as a safe organic solvent. UV–vis absorption

• solubility of a drug leads to low drug absorption. Thus, a sufficient drug concentration in plasma is not achieved, and a high therapeutic effect is not reached. As a result, high dose requirements and more adverse side effects limit the development of phytochemicals in the pharmaceutical industry. BBR

• belongs to the class-III drugs in the biopharmaceutical classification system, indicating that BBR is a lipophilic compound that has poor absorption and low bioavailability [24]. To improve the effectiveness of BBR, many approaches have been proposed, including synergistic effects with other drugs [3

Sodium doping in brookite TiO₂ enhances its photocatalytic activity

• Boxiang Zhuang,
• Honglong Shi,
• Honglei Zhang and
• Zeqian Zhang

Beilstein J. Nanotechnol. 2022, 13, 599–609, doi:10.3762/bjnano.13.52

• activity. Results and Discussion Enhanced photocatalytic activity The photocatalytic activity of the samples calcinated at 300–600 °C for 2 h was measured by the photodegradation of MB under UV light at room temperature. Figure 1a and Figure 1b display the dynamic changes in the absorption spectra of MB

• over two typical samples (400 and 500 °C). The MB concentration versus the irradiation time was determined from the characteristic absorption peak of MB (≈665 nm) acquired by a UV–vis spectrophotometer, as shown in Figure 1c. Samples calcinated at 300 and 400 °C exhibited an excellent photocatalytic

• understand the photocatalytic behavior of a given material. The bandgap values were determined from the diffuse reflectance spectra using the Tauc plot method [26]: where A in Equation 1 is a proportional constant, α is the absorption coefficient, and n depends on the type of electron transition. The bandgap

Approaching microwave photon sensitivity with Al Josephson junctions

• Andrey L. Pankratov,
• Anna V. Gordeeva,
• Leonid S. Revin,
• Dmitry A. Ladeynov,
• Anton A. Yablokov and
• Leonid S. Kuzmin

Beilstein J. Nanotechnol. 2022, 13, 582–589, doi:10.3762/bjnano.13.50

• photon counter in the microwave frequency range. We have measured the switching from the superconducting to the resistive state through the absorption of 10 GHz photons. The dependence of the switching probability on the signal power suggests that the switching is initiated by the simultaneous absorption

• counter can be made on their basis. We use the metastable quasi-equilibrium state of a Josephson junction, which, at low temperatures, is stable enough for thermal fluctuations and quantum tunneling, but can be easily destroyed by absorption of a single photon. We demonstrate few-photon sensitivity of our

• the experiment is done with a more general theory, which considers the absorption probabilities of different numbers of photons. The time traces of setting a current and an external microwave signal to measure the switching probability as a function of power are shown in Figure 1c. First, the current

Revealing local structural properties of an atomically thin MoSe₂ surface using optical microscopy

• Lin Pan,
• Peng Miao,
• Anke Horneber,
• Alfred J. Meixner,
• Pierre-Michel Adam and
• Dai Zhang

Beilstein J. Nanotechnol. 2022, 13, 572–581, doi:10.3762/bjnano.13.49

• fascinating optical and electronic properties [1]. In particular, the optical absorption, direct bandgap, and broken inversion symmetry of 2D transition-metal dichalcogenide (2D-TMDC) monolayers make these materials promising candidates for light-emitting diodes, photodetectors, field-effect transistors

• excitation power-dependent measurement, and the SHG signal shows a quadratic power dependence, shown in the inset of Figure 1e. The absorption spectrum of a CuPc film with a thickness of 10 nm on a glass substrate is shown in Supporting Information File 1, Figure S2. CuPc shows an intensive absorption region

• (called Q-band) from 500 to 800 nm. The absorption peaks situated at 627 and 696 nm are due to the second and the first π–π* transition of the phthalocyanine macrocycle, respectively [30]. Therefore, the Raman measurements for CuPc/MoSe2 are conducted using a 636 nm laser, which shows good resonance with

Detection and imaging of Hg(II) in vivo using glutathione-functionalized gold nanoparticles

• Gufeng Li,
• Shaoqing Li,
• Rui Wang,
• Min Yang,
• Lizhu Zhang,
• Yanli Zhang,
• Wenrong Yang and
• Hongbin Wang

Beilstein J. Nanotechnol. 2022, 13, 549–559, doi:10.3762/bjnano.13.46

• GSH-Rh6G2 was observed (Figure S3, Supporting Information File 1). GSH binds to GNPs via the thiol moiety, leading to an exposure of the amino group. Functional molecules can be directly bound via GSH, providing a stable environment based on the GNP nanostructure. The UV–vis absorption and

• fluorescence spectra of GNPs-GSH-Rh6G2 are shown in Figure 1b,c. Figure 1c shows a strong absorption peak of 13 nm GNPs with the typical plasmon band of gold nanoparticles at 518 nm. However, the absorption peaks of GNPs-GSH and GNPs-GSH-Rh6G2 were slightly redshifted from 518 to 522 and 536 nm, respectively

• , caused by a change in the local dielectric environment and the plasmonic absorption bands of GSH and GSH-Rh6G2-modified GNPs [43][44]. The maximum fluorescence absorption peak of GNPs-GSH-Rh6G2 is at 536 nm, whereas the emission peak is at 560 nm (Figure 1d). The excitation of GNPs-GSH-Rh6G2 was examined

Ciprofloxacin-loaded dissolving polymeric microneedles as a potential therapeutic for the treatment of S. aureus skin infections

• Sharif Abdelghany,
• Walhan Alshaer,
• Yazan Al Thaher,
• Maram Al Fawares,
• Amal G. Al-Bakri,
• Saja Zuriekat and
• Randa SH. Mansour

Beilstein J. Nanotechnol. 2022, 13, 517–527, doi:10.3762/bjnano.13.43

• low bioavailability of orally administered drugs due to poor absorption and enzymatic degradation in the gastrointestinal tract [3][4]. Among the different types of microneedles, dissolving microneedles have attracted research due to their advantages, which include low cost and simple preparation

Design and characterization of polymeric microneedles containing extracts of Brazilian green propolis

• Camila Felix Vecchi,
• Rafaela Said dos Santos,
• Jéssica Bassi da Silva and
• Marcos Luciano Bruschi

Beilstein J. Nanotechnol. 2022, 13, 503–516, doi:10.3762/bjnano.13.42

• or during application, which can increase the permeation of certain molecules by up to 200 times [16]. In addition to being a minimally invasive route, transdermal drug delivery has low drug absorption variability among patients, since the cutaneous metabolism is significantly lower than the

Zinc oxide nanostructures for fluorescence and Raman signal enhancement: a review

• Ioana Marica,
• Fran Nekvapil,
• Maria Ștefan,
• Cosmin Farcău and
• Alexandra Falamaș

Beilstein J. Nanotechnol. 2022, 13, 472–490, doi:10.3762/bjnano.13.40

• nanostructures. Besides this field enhancement, the excitation of the collective oscillations of the conduction electrons in metallic NPs results in strong absorption and scattering of light in the visible range of the electromagnetic spectrum. Moreover, even larger EM field enhancement can be obtained in noble

• nanostructures by combining them with noble metal NPs and tuning the peak location of the LSPR near to the visible region of the EM spectrum and by creating “hot spots” in ZnO ordered nanostructures [15]. This results in strong scattering and absorption of incident light, thus influencing optical processes such

• as SEF, SERS [16][17], infrared absorption, and even second harmonic generation [18], which can improve the performance of optical sensors and optoelectronic devices. ZnO alone and in combination with noble metals has been recently used for the development of SERS substrates [15][19] due to several

Investigation of electron-induced cross-linking of self-assembled monolayers by scanning tunneling microscopy

• Patrick Stohmann,
• Sascha Koch,
• Yang Yang,
• Christopher David Kaiser,
• Julian Ehrens,
• Jürgen Schnack,
• Niklas Biere,
• Dario Anselmetti,
• Armin Gölzhäuser and
• Xianghui Zhang

Beilstein J. Nanotechnol. 2022, 13, 462–471, doi:10.3762/bjnano.13.39

• separation [36][37][38][39][40][41][42]. The interactions between aromatic SAMs and electrons have been studied by X-ray photoelectron spectroscopy (XPS), near-edge X-ray-absorption fine-structure (NEXAFS) technique [43][44][45][46][47][48][49], infrared spectroscopy [43][50][51][52], high-resolution

Selected properties of Al_xZn_yO thin films prepared by reactive pulsed magnetron sputtering using a two-element Zn/Al target

• Witold Posadowski,
• Artur Wiatrowski,
• Jarosław Domaradzki and
• Michał Mazur

Beilstein J. Nanotechnol. 2022, 13, 344–354, doi:10.3762/bjnano.13.29

• maxima move apart. The observed changes suggest that the film thickness decreased with X. To better visualize the effect of the substrate placement on the optical properties of the deposited films, in Figure 5b, the fundamental absorption edge (the cut-off wavelength, λcut-off) as a function of X is

• presented. In the area directly above the target (X = 0–50 mm), the position of the optical absorption edge of thin films is quite similar (Figure 5b). Moving away from the axis beyond the area above the target (X = 50–100 mm), the optical absorption edge of the spectra shifts in the direction towards

A broadband detector based on series YBCO grain boundary Josephson junctions

• Egor I. Glushkov,
• Alexander V. Chiginev,
• Leonid S. Kuzmin and
• Leonid S. Revin

Beilstein J. Nanotechnol. 2022, 13, 325–333, doi:10.3762/bjnano.13.27

• decreases. Starting from five JJs in series, Ptotal reaches saturation with a level below 1. This is due to the fact that the length of the meander becomes so large that it begins to affect the absorption at a given frequency and cross resonances reduce the receiving properties of the system. Numerical

Coordination-assembled myricetin nanoarchitectonics for sustainably scavenging free radicals

• Xiaoyan Ma,
• Haoning Gong,
• Kenji Ogino,
• Xuehai Yan and
• Ruirui Xing

Beilstein J. Nanotechnol. 2022, 13, 284–291, doi:10.3762/bjnano.13.23

• scavenging activity First, a solution of 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical cations (ABTS+) solution was prepared. 7 mM of ABTS solution was mixed with 2.45 mM of potassium persulfate solution and kept for 12 h in the dark. The UV–vis absorption intensity of a 0.7 mM ABTS solution

• (diluted in PBS) was 0.7 ± 0.02. A certain volume of diluted ABTS+ solution was added to different concentrations of Myr, GSH, and MZG. A UV–vis spectrophotometer was used to record the absorption intensity of ABTS+ at 734 nm. The radical scavenging rate was calculated according to the following equation

• : MZG nanoparticles and Myr/GSH complex were dispersed in H2O for 5 days. Diluted ABTS solution was added with the same concentration of MZG and Myr/GSH complex (equivalent concentration of Myr and GSH: 4 μg·mL−1 and 8 μg·mL−1, respectively) every day. The UV–vis absorption intensity of ABTS at 734 nm

Photothermal ablation of murine melanomas by Fe₃O₄ nanoparticle clusters

• Xue Wang,
• Lili Xuan and
• Ying Pan

Beilstein J. Nanotechnol. 2022, 13, 255–264, doi:10.3762/bjnano.13.20

• tumor cells, while leaving healthy neighbor tissues intact [4][5]. Treatment specificity is further guaranteed by the high transmissivity and low absorption of NIR light when penetrating through biological tissues, making PTT a minimally invasive approach for tumor intervention. One such type of

• , whereas exposure to and subsequent absorption of NIR light by iron oxide nanoparticles promotes NIR-induced hyperthermia [10]. Although magnetic hyperthermia has been widely used in biomedical research, it is subject to several limitations such as the need for sophisticated equipment, cellular confinement

• effects of alumina-coated Fe3O4 nanoparticles against bacteria upon exposure to NIR light [13]. Further studies with esophageal cancer demonstrate that Fe3O4 nanoparticles induce hyperthermia post absorption to suppress tumor growth in a dosage-dependent manner [14]. However, due to very high dosage

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

• -ligand charge transfer absorption bands and a relatively long lifetime of the triplet state as well as voltage-driven molecular switching in solid-state molecular junctions [11][12][13][14][15]. In addition, Ru(TP)2-complexes and the corresponding supramolecular wires exhibit a rod-like structure, which

• was verified by infrared reflection absorption spectroscopy (IRRAS) and surface-enhanced Raman spectroscopy in combination with density functional theory calculations, as well as variable angle spectroscopic ellipsometry. Based on this wire formation protocol the on-chip preparation of Ru(TP)2-complex

Engineered titania nanomaterials in advanced clinical applications

• Padmavati Sahare,
• Paulina Govea Alvarez,
• Juan Manual Sanchez Yanez,
• Gabriel Luna-Bárcenas,
• Samik Chakraborty,
• Sujay Paul and
• Miriam Estevez

Beilstein J. Nanotechnol. 2022, 13, 201–218, doi:10.3762/bjnano.13.15

• /kg body weight did not lead to absorption from the gastrointestinal tract into the blood, urine, or other internal organs. Furthermore, human studies revealed that gastrointestinal absorption of TiO2 nps into blood and urine was minimal and that the nps are expected to be removed mostly by renal

• selective spectral absorption in the UV region above 3.2 eV for anatase and 3.0 eV for the rutile phase. The absorbed UV light creates electron–hole pairs that migrate to the surface, causing a redox reaction and leading to ROS formation [77]. Since energy levels are not available for TiO2 nps to facilitate

• cervical tumors by incorporating zinc phthalocyanine (ZnPc) as photosensitizer into TiO2 nps. The result showed a higher cellular uptake of ZnPc-TiO2 and an increased PDT efficiency compared ot Zn alone [114]. Since photocatalytic absorption generally occurs at the surface, surface modification acts as the

A photonic crystal material for the online detection of nonpolar hydrocarbon vapors

• Evgenii S. Bolshakov,
• Aleksander V. Ivanov,
• Andrei A. Kozlov,
• Anton S. Aksenov,
• Elena V. Isanbaeva,
• Sergei E. Kushnir,
• Aleksei D. Yapryntsev,
• Aleksander E. Baranchikov and
• Yury A. Zolotov

Beilstein J. Nanotechnol. 2022, 13, 127–136, doi:10.3762/bjnano.13.9

• detection of volatile organic compounds [30][31][32]. In most cases, the response of such sensors is a change in mass recorded using a quartz microbalance. A simpler design and research method made it possible to investigate in more detail the processes occurring during the absorption of solvents. The

• analytical response rates and the toxicity of the detected compounds. Since the absorption of hydrocarbon vapors is responsible for the delivery of the analyte to the photonic crystal, a change in the sensor sensitivity is possible by varying the thickness of the sensitive PDMS layer. In the experiments

• polymer regarding material strength. Method Figure 8a shows the scheme of the experimental equipment. It consists of the spectrophotometer “eye-one Pro” and a peripheral device, which is made of black composite material based on epoxy resins for visible-light absorption and to elude backward reflection

Tin dioxide nanomaterial-based photocatalysts for nitrogen oxide oxidation: a review

• Viet Van Pham,
• Hong-Huy Tran,
• Thao Kim Truong and
• Thi Minh Cao

Beilstein J. Nanotechnol. 2022, 13, 96–113, doi:10.3762/bjnano.13.7

• in recent years. There are many methods for controlling and removing NOx, such as reducing the burning temperature, reducing the residence time at peak temperature, chemical reduction or oxidation of NOx, removal of nitrogen from combustion fuels, and sorption, both adsorption and absorption [7][8

• increasing film thickness [45]. Zhou et al. indicated that the direct bandgap transition of SnO2 has an absorption coefficient α and the optical bandgap (Eg) can be determined by the calculation of α(hν)2 ∝ (hν − Eg)1/2/hν, and the plot of α(hν)2 vs photon energy hν, respectively. For example, the bandgap of

• a SnO2 thin film with a thickness of about 130 nm is 3.597 eV [42]. The reported bandgap of bulk SnO2 is 3.6 eV. Changing the morphology, particle size, or the formation of OVs or defects narrow the bandgap. In the study of Babu et al., a redshift of the absorption edge was observed when SnO2

Theranostic potential of self-luminescent branched polyethyleneimine-coated superparamagnetic iron oxide nanoparticles

• Rouhollah Khodadust,
• Ozlem Unal and
• Havva Yagci Acar

Beilstein J. Nanotechnol. 2022, 13, 82–95, doi:10.3762/bjnano.13.6

• when attached to the iron oxide surface since SPIONs have strong absorption in the UV and visible range of the spectrum [33]. Alternatively, PEI-bound luminescent nanoparticles, such as quantum dots or graphene nanoparticles, are also being studied to combine optical imaging and gene transfection

Influence of magnetic domain walls on all-optical magnetic toggle switching in a ferrimagnetic GdFe film

• Rahil Hosseinifar,
• Evangelos Golias,
• Ivar Kumberg,
• Quentin Guillet,
• Karl Frischmuth,
• Sangeeta Thakur,
• Mario Fix,
• Manfred Albrecht,
• Florian Kronast and
• Wolfgang Kuch

Beilstein J. Nanotechnol. 2022, 13, 74–81, doi:10.3762/bjnano.13.5

• ]. Due to the helicity-dependent absorption of the laser fluence in the sample as a consequence of magnetic circular dichroism and a sharp intensity threshold for toggle switching, this can also lead to helicity-dependent all-optical single-pulse switching [4][19]. Important for applications of all

• magnetic circular dichroism (XMCD) at the Gd M5 absorption edge at 1182.6 eV photon energy was used as magnetic contrast mechanism. A small electromagnet mounted inside the sample holder allows for applying a magnetic field to the sample for demagnetizing or creating domains. Before the start of each

Sputtering onto liquids: a critical review

• Anastasiya Sergievskaya,
• Adrien Chauvin and
• Stephanos Konstantinidis

Beilstein J. Nanotechnol. 2022, 13, 10–53, doi:10.3762/bjnano.13.2

Heating ability of elongated magnetic nanoparticles

• Elizaveta M. Gubanova,
• Nikolai A. Usov and
• Vladimir A. Oleinikov

Beilstein J. Nanotechnol. 2021, 12, 1404–1412, doi:10.3762/bjnano.12.104

• .12.104 Abstract Low-frequency hysteresis loops and specific absorption rate (SAR) of various assemblies of elongated spheroidal magnetite nanoparticles have been calculated for a range of particle semiaxis ratios a/b = 1.0–3.0. The SAR of a dilute randomly oriented assembly of magnetite nanoparticles in

• of magnitude with an increase in the volume fraction of nanoparticles in a cluster in the range of 0.04–0.2. Keywords: elongated magnetic nanoparticles; magnetic hyperthermia; numerical simulation; specific absorption rate; Introduction Magnetic nanoparticle assemblies have great potential for the

• cases this stops the tumor growth and results in its decay. However, it are magnetic nanoparticles with low toxicity and a high specific absorption rate (SAR) of the energy of the ac magnetic field that are needed in magnetic hyperthermia. The use of optimized assemblies of magnetic nanoparticles can