Search results

Search for "absorption coefficient" in Full Text gives 102 result(s) in Beilstein Journal of Nanotechnology.

Ar+ implantation-induced tailoring of RF-sputtered ZnO films: structural, morphological, and optical properties

  • Manu Bura,
  • Divya Gupta,
  • Arun Kumar and
  • Sanjeev Aggarwal

Beilstein J. Nanotechnol. 2025, 16, 872–886, doi:10.3762/bjnano.16.66

Graphical Abstract
  • defects as described in GXRD and Raman studies. The optical bandgap (Eg) values of samples have been estimated employing Tauc’s relation [45]: where α and hν are absorption coefficient and photon energy, respectively, C represents constant, and n elucidates the transition type (n is 2/3 for forbidden
  • , the absorption coefficient varies exponentially with photon energy [45]: Here, α0 represents a constant, α is the absorption coefficient, and E0 stands for the Urbach energy, which is calculated by taking the inverse of the slope of the plot between ln(α(λ)) and photon energy (E = hν). Since α is
PDF
Album
Full Research Paper
Published 11 Jun 2025

Morphology and properties of pyrite nanoparticles obtained by pulsed laser ablation in liquid and thin films for photodetection

  • Akshana Parameswaran Sreekala,
  • Bindu Krishnan,
  • Rene Fabian Cienfuegos Pelaes,
  • David Avellaneda Avellaneda,
  • Josué Amílcar Aguilar-Martínez and
  • Sadasivan Shaji

Beilstein J. Nanotechnol. 2025, 16, 785–805, doi:10.3762/bjnano.16.60

Graphical Abstract
  • a narrow bandgap (0.95 eV), high light absorption coefficient (≈105 cm−1), excellent properties in photoelectric conversion, and has enormous potential as an efficient photodetector system and in lithium batteries [1][2]. The prevalent forms of FeS2 are cubic-system pyrite and the orthorhombic
  • its ability to absorb UV wavelengths [32]. This concept was used to fabricate photodetectors (PDs) using pyrite NPs on Si substrate as it inherently has the advantages of exceptional photo-absorption, high mobility, and high absorption coefficient as initially mentioned. Self-powering PDs have a
PDF
Album
Supp Info
Full Research Paper
Published 03 Jun 2025

Efficiency of single-pulse laser fragmentation of organic nutraceutical dispersions in a circular jet flow-through reactor

  • Tina Friedenauer,
  • Maximilian Spellauge,
  • Alexander Sommereyns,
  • Verena Labenski,
  • Tuba Esatbeyoglu,
  • Christoph Rehbock,
  • Heinz P. Huber and
  • Stephan Barcikowski

Beilstein J. Nanotechnol. 2025, 16, 711–727, doi:10.3762/bjnano.16.55

Graphical Abstract
  • -dependent difference. In the material systems examined here, this difference can be attributed either to the absorption coefficient of the bulk material or the diameter of the educt particles, a correlation more closely examined in the consecutive section. Proposed MP-LFL mechanism While both commercially
PDF
Album
Supp Info
Full Research Paper
Published 26 May 2025

Engineered PEG–PCL nanoparticles enable sensitive and selective detection of sodium dodecyl sulfate: a qualitative and quantitative analysis

  • Soni Prajapati and
  • Ranjana Singh

Beilstein J. Nanotechnol. 2025, 16, 385–396, doi:10.3762/bjnano.16.29

Graphical Abstract
  • . Polystyrene latex absorption coefficient and refractive index were used to measure synthesized nanoparticles, prefilled in the software with values of 0.01 and 1.59, respectively. All measurements were performed at 25 °C. The surface morphology of PEG–PCL nanoparticles was analyzed using scanning electron
PDF
Album
Full Research Paper
Published 20 Mar 2025

Pulsed laser in liquid grafting of gold nanoparticle–carbon support composites

  • Madeleine K. Wilsey,
  • Teona Taseska,
  • Qishen Lyu,
  • Connor P. Cox and
  • Astrid M. Müller

Beilstein J. Nanotechnol. 2025, 16, 349–361, doi:10.3762/bjnano.16.26

Graphical Abstract
  • nanosecond pulses, graphite has an effective absorption coefficient of 5 µm−1 [26], resulting in an ablation threshold fluence of 0.7 J·cm−2 [27]; thus, our chosen fluence was well below this ablation threshold. The critical melting fluence of graphite has been reported to be 0.13 J·cm−2 [28], suggesting
PDF
Album
Supp Info
Full Research Paper
Published 07 Mar 2025

Tailoring of physical properties of RF-sputtered ZnTe films: role of substrate temperature

  • Kafi Devi,
  • Usha Rani,
  • Arun Kumar,
  • Divya Gupta and
  • Sanjeev Aggarwal

Beilstein J. Nanotechnol. 2025, 16, 333–348, doi:10.3762/bjnano.16.25

Graphical Abstract
  • , 400 °C, 500 °C, and 600 °C, respectively. Figure 5C shows the absorption coefficient as a function of the wavelength for ZnTe/Qz films at different substrate temperatures. From Figure 5C, it is observed that α has very low values at higher wavelengths (≥600 nm). The absorption coefficient increases
  • very slowly in this region. In contrast, a sharp increase in α is observed in the lower-wavelength (≤600 nm) region. This type of variation in absorption coefficient points toward the existence of both direct and indirect bandgaps in a material. ZnTe films exhibit both direct and indirect transitions
  • [35][36]. Therefore, in this study we have determined both direct and indirect bandgaps. The Tauc relation was used to determine the optical bandgaps (Eg) of ZnTe/Qz films [34] where h represents the Planck constant, ν is the frequency of the incident light, α is the absorption coefficient, and C is
PDF
Album
Supp Info
Full Research Paper
Published 05 Mar 2025

TiO2 immobilized on 2D mordenite: effect of hydrolysis conditions on structural, textural, and optical characteristics of the nanocomposites

  • Marina G. Shelyapina,
  • Rosario Isidro Yocupicio-Gaxiola,
  • Gleb A. Valkovsky and
  • Vitalii Petranovskii

Beilstein J. Nanotechnol. 2025, 16, 128–140, doi:10.3762/bjnano.16.12

Graphical Abstract
  • diffuse reflectance spectra. In this method, it is assumed that the energy-dependent absorption coefficient α can be written as where h is the Planck constant, hν is the photon energy, and B is a constant. The factor n depends on the nature of the electron transition, that is, n = 1/2 for direct and n = 2
PDF
Album
Full Research Paper
Published 10 Feb 2025

Heterogeneous reactions in a HFCVD reactor: simulation using a 2D model

  • Xochitl Aleyda Morán Martínez,
  • José Alberto Luna López,
  • Zaira Jocelyn Hernández Simón,
  • Gabriel Omar Mendoza Conde,
  • José Álvaro David Hernández de Luz and
  • Godofredo García Salgado

Beilstein J. Nanotechnol. 2024, 15, 1627–1638, doi:10.3762/bjnano.15.128

Graphical Abstract
  • ratio x = [O]/[Si], which is determined by controlling key parameters in the deposition process [2]. This ratio determines optical and electrical properties such as bandgap energy, absorption coefficient, photoluminescence, refractive index, and electrical conductivity [3]. SiOx cannot only be obtained
PDF
Album
Full Research Paper
Published 17 Dec 2024

Quantum-to-classical modeling of monolayer Ge2Se2 and its application in photovoltaic devices

  • Anup Shrivastava,
  • Shivani Saini,
  • Dolly Kumari,
  • Sanjai Singh and
  • Jost Adam

Beilstein J. Nanotechnol. 2024, 15, 1153–1169, doi:10.3762/bjnano.15.94

Graphical Abstract
  • successfully synthesized [28][29][30][31]. Its remarkable features, such as low cost, abundance, environmental friendliness, and many interesting physical properties, indicate a broad range of possible applications in sustainable electronics and photonics [32]. Notably, a high absorption coefficient has been
  • investigated structure exhibits strongly anisotropic optical properties for which the parametric values depend on the direction of the chosen plane. Dielectric function and absorption coefficient The static dielectric constants (real part of εr at ω = 0), along the in-plane (XX) and out-of-plane (ZZ) direction
  • , which further leads to higher transition possibilities. The absorption coefficient elucidates the rate at which light intensity diminishes while entering the material. It primarily depends upon the imaginary part of the refractive index k(λ) = Im{n(λ)} and the wavelength of the incident light λ, as per
PDF
Album
Full Research Paper
Published 11 Sep 2024

Bolometric IR photoresponse based on a 3D micro-nano integrated CNT architecture

  • Yasameen Al-Mafrachi,
  • Sandeep Yadav,
  • Sascha Preu,
  • Jörg J. Schneider and
  • Oktay Yilmazoglu

Beilstein J. Nanotechnol. 2024, 15, 1030–1040, doi:10.3762/bjnano.15.84

Graphical Abstract
  • [8], the effective reflection from the forest decreased very rapidly. MWCNTs have also been used as absorbers in the infrared region (2–20 μm) with an optical absorption coefficient above 90% [10]. Similar values were achieved for different synthesis temperatures (500–700 °C) with different CNT
PDF
Album
Supp Info
Full Research Paper
Published 15 Aug 2024

Controllable physicochemical properties of WOx 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

Graphical Abstract
  • fascinating optical and electrical properties [1]. WOx is a wide-bandgap oxide semiconductor with a large excitonic binding energy of 0.15 eV and a high optical absorption coefficient (≥104 cm−1 in the UV region) [2]. These, in conjunction with decent carrier mobility (12 cm2·V−1·s−1), make this material an
  • -WOx films. The value of Eg is estimated by employing the well-known Tauc’s equation [34]: where hv is the energy of the incident photons (in eV), α is the optical absorption coefficient, k is a constant, and n is a constant whose value depends on the type of transition (n = 2 for direct and n = 1/2
PDF
Album
Supp Info
Full Research Paper
Published 02 Apr 2024

Fluorescent bioinspired albumin/polydopamine nanoparticles and their interactions with Escherichia coli cells

  • Eloïse Equy,
  • Jordana Hirtzel,
  • Sophie Hellé,
  • Béatrice Heurtault,
  • Eric Mathieu,
  • Morgane Rabineau,
  • Vincent Ball and
  • Lydie Ploux

Beilstein J. Nanotechnol. 2023, 14, 1208–1224, doi:10.3762/bjnano.14.100

Graphical Abstract
  • measured by dynamic light scattering (DLS) using a Zetasizer Nano ZS from Malvern Panalytical (Malvern, UK). Measurements were performed while taking into account a refractive index of 1.73 − 0.02i for PDA (the imaginary part corresponds to the absorption coefficient) at a wavelength of 589 nm, that is
PDF
Album
Supp Info
Full Research Paper
Published 22 Dec 2023

Nanoarchitectonics of photothermal materials to enhance the sensitivity of lateral flow assays

  • Elangovan Sarathkumar,
  • Rajasekharan S. Anjana and
  • Ramapurath S. Jayasree

Beilstein J. Nanotechnol. 2023, 14, 988–1003, doi:10.3762/bjnano.14.82

Graphical Abstract
  • nanomaterials become larger, they deflect more light than they absorb, resulting in reduced photothermal conversion [53]. This is because the ratio between absorption coefficient (µa) and scattering coefficient (µs) is higher for smaller particles. Compared to the 80 nm gold nanoparticles (µa = 67.88 µm−1), 40
PDF
Album
Review
Published 04 Oct 2023

Plasmonic nanotechnology for photothermal applications – an evaluation

  • A. R. Indhu,
  • L. Keerthana and
  • Gnanaprakash Dharmalingam

Beilstein J. Nanotechnol. 2023, 14, 380–419, doi:10.3762/bjnano.14.33

Graphical Abstract
  • interaction between inner-core and outer-shell plasmons, PT energy transduction is significantly more effective. The absorption coefficient (Cabs) of the nanomatryushka (NM) can be calculated by varying the volumetric factor of the different layers of the nanostructures and the refractive index of the
PDF
Album
Review
Published 27 Mar 2023

Electrical and optical enhancement of ITO/Mo bilayer thin films via laser annealing

  • Abdelbaki Hacini,
  • Ahmad Hadi Ali,
  • Nurul Nadia Adnan and
  • Nafarizal Nayan

Beilstein J. Nanotechnol. 2022, 13, 1589–1595, doi:10.3762/bjnano.13.133

Graphical Abstract
  • before and after laser annealing. The bandgap energy Eg was determined using the following equation (Tauc relation) [28]: where α is the absorption coefficient, hν is the photon energy; A is a constant, Eg is the bandgap energy, n = 0.5 for a direct bandgap, and n = 2 for an indirect bandgap. The bandgap
PDF
Album
Full Research Paper
Published 28 Dec 2022

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

Graphical Abstract
  • spectroscopy (DRS) was carried out to measure the optical bandgap of the semiconductor materials through the Tauc method using the absorption coefficient α of the material, according to Equation 1 [42]: where h, ν, Eg, and B are the Planck constant, the frequency of the photon, the bandgap energy, and a
PDF
Album
Supp Info
Full Research Paper
Published 16 Dec 2022

Facile preparation of Au- and BODIPY-grafted lipid nanoparticles for synergized photothermal therapy

  • Yuran Wang,
  • Xudong Li,
  • Haijun Chen and
  • Yu Gao

Beilstein J. Nanotechnol. 2022, 13, 1432–1444, doi:10.3762/bjnano.13.118

Graphical Abstract
  • organic PTAs, boron dipyrromethenes (BODIPYs) have attracted increasing attention because of high molar absorption coefficient and photochemical stability [11]. Besides, fabricating BODIPYs with halogenated substituents can improve the photothermal conversion efficiency during PTT [12]. However, BODIPYs
PDF
Album
Full Research Paper
Published 02 Dec 2022

LED-light-activated photocatalytic performance of metal-free carbon-modified hexagonal boron nitride towards degradation of methylene blue and phenol

  • Nirmalendu S. Mishra and
  • Pichiah Saravanan

Beilstein J. Nanotechnol. 2022, 13, 1380–1392, doi:10.3762/bjnano.13.114

Graphical Abstract
  • formation of C–N moieties in the BN framework [16]. where h, α, c, E denote the Planck’s constant, absorption coefficient derived from the Lambert’s equation, speed of light (3 × 108 m s−1), and energy, respectively. The value of n (n = 4 for direct bandgap and n = 1 for indirect bandgap) depends upon the
PDF
Album
Full Research Paper
Published 22 Nov 2022

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

Graphical Abstract
  • equation as described in Equations 5–7 [43]: where E is the photon energy (eV), h is Planck’s constant (4.132·10−15 eV·s), ν is the photon frequency (s−1), c is the velocity of light (nm·s−1), λ is the wavelength (nm), α is the absorption coefficient, B is a constant, and Eg is the bandgap energy (eV), R
PDF
Album
Supp Info
Full Research Paper
Published 18 Oct 2022

Numerical study on all-optical modulation characteristics of quantum cascade lasers

  • Biao Wei,
  • Haijun Zhou,
  • Guangxiang Li and
  • Bin Tang

Beilstein J. Nanotechnol. 2022, 13, 1011–1019, doi:10.3762/bjnano.13.88

Graphical Abstract
  • /τsp is the spontaneous emission rate of the upper laser subband, α is the cavity absorption coefficient, β is the rate of spontaneous emission getting into the laser modes, nk is the k-th subband population, S is the photon population in the cavity, and the laser upper and lower subbands are denoted
PDF
Album
Full Research Paper
Published 23 Sep 2022

Efficient liquid exfoliation of KP15 nanowires aided by Hansen's empirical theory

  • Zhaoxuan Huang,
  • Zhikang Jiang,
  • Nan Tian,
  • Disheng Yao,
  • Fei Long,
  • Yanhan Yang and
  • Danmin Liu

Beilstein J. Nanotechnol. 2022, 13, 788–795, doi:10.3762/bjnano.13.69

Graphical Abstract
  • KP15 dispersions. The Lambert–Beer law (Equation 3) was then used to measure the concentration of the KP15 dispersions: where A is the absorbance, K is the absorption coefficient of the material, b is the absorbing layer thickness (which in this work is the width of the cuvette, i.e., 1 cm), and C is
  • the concentration of the KP15 dispersions. The absorbance A and the absorption coefficient K are related to the wavelength of the incident light. To determine A and K, it is necessary to choose a specific incident wavelength. The bandgap of bulk KP15 is approx. 1.75 eV [20]. However, according to our
  • influence of the surface state, a wavelength (800 nm) which is far away from the bandgap of KP15 bulk and surface state in the KP15 nanowires was chosen. Some dispersions for which we predetermined the concentration were prepared to fit and determine the absorption coefficient K. Solutions of five different
PDF
Album
Supp Info
Full Research Paper
Published 17 Aug 2022

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

Graphical Abstract
  • 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
PDF
Album
Supp Info
Full Research Paper
Published 05 Jul 2022

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

Graphical Abstract
  • 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
PDF
Album
Review
Published 21 Jan 2022

First-principles study of the structural, optoelectronic and thermophysical properties of the π-SnSe for thermoelectric applications

  • Muhammad Atif Sattar,
  • Najwa Al Bouzieh,
  • Maamar Benkraouda and
  • Noureddine Amrane

Beilstein J. Nanotechnol. 2021, 12, 1101–1114, doi:10.3762/bjnano.12.82

Graphical Abstract
  • [73]: where P and ω represent the principal value and angular frequency, respectively. The other optical parameters, such as the absorption coefficient α(ω), energy loss function L(ω), refractive index n(ω), extinction coefficient K(ω), reflectivity R(ω), and conductivity σ(ω) can be easily obtained
  • that two important peaks (α and β) are located in the visible region. Beyond the β peak, ε2(ω) shows a decreasing trend at higher energies. The absorption coefficient α(ω) is presented in Figure 11c as a function of photon energy. The absorption coefficient demonstrates all the information of the
  • α(ω) π-SnSe is zero until the photon energy is lower as compared to its energy bandgap of 1.41 eV. After this energy, the π-SnSe alloy displays a sharp increase of absorption coefficient α(ω) up to 139.6 104/cm at 6 eV. After this energy value, α(ω) starts to decrease with the increase in photon
PDF
Album
Full Research Paper
Published 05 Oct 2021

Revealing the formation mechanism and band gap tuning of Sb2S3 nanoparticles

  • Maximilian Joschko,
  • Franck Yvan Fotue Wafo,
  • Christina Malsi,
  • Danilo Kisić,
  • Ivana Validžić and
  • Christina Graf

Beilstein J. Nanotechnol. 2021, 12, 1021–1033, doi:10.3762/bjnano.12.76

Graphical Abstract
  • are several requirements for materials to be eligible for application in the field of photovoltaics, such as high absorption performance, nontoxicity, abundance, efficiency, and low cost. As a semiconductor with a low band gap and a high absorption coefficient, antimony(III) sulfide (Sb2S3) has become
  • receive the band gap values of the material [37][38]. As shown in Equation 1, the absorption coefficient α is expressed by the Planck constant h, the photon frequency ν, a constant B, which Davis and Mott described as the magnitude of the optical absorption constant [38], and a transition factor γ: The
  • transition factor γ depends on the type of the band gap transition. It equals 1/2 for a direct allowed transition and 2 for an indirect allowed transition. For reflectance data, α is expressed by the Kubelka–Munk function F(R∞) (Equation 2), which is the quotient of the absorption coefficient k and the
PDF
Album
Supp Info
Full Research Paper
Published 10 Sep 2021
Other Beilstein-Institut Open Science Activities