Emerging strategies in the sustainable removal of antibiotics using semiconductor-based photocatalysts

• Yunus Ahmed,
• Keya Rani Dutta,
• Parul Akhtar,
• Md. Arif Hossen,
• Md. Jahangir Alam,
• Obaid A. Alharbi,
• Hamad AlMohamadi and
• Abdul Wahab Mohammad

Beilstein J. Nanotechnol. 2025, 16, 264–285, doi:10.3762/bjnano.16.21

• its low bandgap energy (2.4 to 2.8 eV) [114]. However, the usage of this material in environmental remediation processes is questionable [115][116][117] because the electrons generated by light in the CB of WO3 (about +0.5 V vs NHE) have a weaker positive potential compared to the reduction potential

Recent advances in photothermal nanomaterials for ophthalmic applications

• Jiayuan Zhuang,
• Linhui Jia,
• Chenghao Li,
• Rui Yang,
• Jiapeng Wang,
• Wen-an Wang,
• Heng Zhou and
• Xiangxia Luo

Beilstein J. Nanotechnol. 2025, 16, 195–215, doi:10.3762/bjnano.16.16

• their bandgap energy (incident wavelength from approximately 310 to 1240 nm) [73], leading to the generation of electron–hole pairs that possess energy equivalent to the bandgap [74]. Once these excited electrons are transferred to impurities, defects, or surface dangling bonds [75], they release energy

Clays enhanced with niobium: potential in wastewater treatment and reuse as pigment with antibacterial activity

• Silvia Jaerger,
• Patricia Appelt,
• Mario Antônio Alves da Cunha,
• Fabián Ccahuana Ayma,
• Ricardo Schneider,
• Carla Bittencourt and
• Fauze Jacó Anaissi

Beilstein J. Nanotechnol. 2025, 16, 141–154, doi:10.3762/bjnano.16.13

• residues from the original organic matter, thus avoiding the disposal of sludge [8]. This approach allows the removal of various organic pollutants, including textile dyes, using solid semiconductors (e.g., NbOPO4 and Nb2O5) and photons (with energy greater than the bandgap energy of the semiconductor) to

• present profiles like BE clay, with intense absorption in the UV region with a sharp drop of around 550 nm [8]. This fact indicates the feasibility of activating the A-BEPh, A-BEPhP, A-BEOx, and A-BEOXPh samples under visible light (above 400 nm) [8]. The indirect bandgap energy values for the BE, NbOPO4

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

• the material. However, as it was shown in [44], the formation of a dense anatase phase has a strong influence on both the value of water adsorption energy and the distribution of water adsorption centers. UV–vis spectrometry To determine the bandgap energy Eg, the Tauc method was applied to the

• studied nanocomposites transformed using Equation 6 with n = 2 (since TiO2 is an indirect bandgap semiconductor). Semiconductor materials are characterized by a steep linear increase in light absorption with increasing energy. The bandgap energy can be estimated from the point of intersection of the x

Comparison of organic and inorganic hole transport layers in double perovskite material-based solar cell

• Deepika K and
• Arjun Singh

Beilstein J. Nanotechnol. 2025, 16, 119–127, doi:10.3762/bjnano.16.11

• the modeling of graded device structures up to seven layers and the computing of device parameters such as bandgap energy, efficiency, and J–V characteristics [19]. It helps in understanding the various functions of the device in more detail while indicating the aspects that have the highest impact on

Characterization of ZnO nanoparticles synthesized using probiotic Lactiplantibacillus plantarum GP258

• Prashantkumar Siddappa Chakra,
• Aishwarya Banakar,
• Shriram Narayan Puranik,
• Vishwas Kaveeshwar,
• C. R. Ravikumar and
• Devaraja Gayathri

Beilstein J. Nanotechnol. 2025, 16, 78–89, doi:10.3762/bjnano.16.8

• + cations. These findings offer information about the structure and chemical interactions within the ZnO NPs (Figure 2b). UV–vis absorption The UV–Vis absorption spectra of ZnO NPs, presented in Figure 2c, establish a distinct absorption peak at 3.16 eV, revealing the characteristic bandgap energy for ZnO

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

• 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

Strain-induced bandgap engineering in 2D ψ-graphene materials: a first-principles study

• Kamal Kumar,
• Nora H. de Leeuw,
• Jost Adam and
• Abhishek Kumar Mishra

Beilstein J. Nanotechnol. 2024, 15, 1440–1452, doi:10.3762/bjnano.15.116

• strain levels was observed to be direct. Variation of (i) bandgap energy Eg and (ii) buckling height h of (a) ψ-graphene, (b) ψ-graphone, and (c) ψ-graphane under applied biaxial mechanical strain. The bandgap Eg and buckling height h of ψ-graphane vary in an almost linear fashion. Optimized lattice

• (h), and bandgap energy (Eg) of ψ-graphene on applying lattice strain. Lattice parameters (a, b), C–C bond lengths (d1, dC–C), average C–C bond length (dC–C(avg)), buckling height (h), and bandgap energy (Eg) of ψ-graphone on applying lattice strain. Lattice parameters (a, b), C–C bond lengths (d1

• , dC–C), average C–C bond length (dC–C(avg)), buckling height (h), and bandgap energy (Eg) of ψ-graphane on applying lattice strain. Supporting Information We have given relaxed structures, PDOS, and EBS plots of ψ-graphene, ψ-graphone, and ψ-graphane in the Supporting Information. We have also given

Various CVD-grown ZnO nanostructures for nanodevices and interdisciplinary applications

• The-Long Phan,
• Le Viet Cuong,
• Vu Dinh Lam and
• Ngoc Toan Dang

Beilstein J. Nanotechnol. 2024, 15, 1390–1399, doi:10.3762/bjnano.15.112

• comparison to other compounds [4][5][6]. Specifically, its large bandgap energy Eg ≈ 3.4 eV is comparable to GaN – a typical material for blue-light-emitting diode (LED) technology [7][8]. Also, its exciton binding energy is higher than the thermal energy at 300 K, and it has high-quality optical

Green synthesis of carbon dot structures from Rheum Ribes and Schottky diode fabrication

• Muhammed Taha Durmus and
• Ebru Bozkurt

Beilstein J. Nanotechnol. 2024, 15, 1369–1375, doi:10.3762/bjnano.15.110

• this diode were examined. The synthesized CDs are spherical with an average size of 5.5 nm, have a negative surface charge and contain 73.3 atom % C, 24.0 atom % O, and 2.7 atom % N. The CDs exhibit fluorescence at approximately 394 nm. The layer thickness and bandgap energy of the prepared CDs film

• new synthesized CDs were determined, and their structural and optical characterization was performed. The usability of the new CDs in diode fabrication as an application area was discussed. The layer thickness and bandgap energy for the prepared CDs film from SEM and UV–vis absorption measurements

Photocatalytic methane oxidation over a TiO₂/SiNWs p–n junction catalyst at room temperature

• Qui Thanh Hoai Ta,
• Luan Minh Nguyen,
• Ngoc Hoi Nguyen,
• Phan Khanh Thinh Nguyen and
• Dai Hai Nguyen

Beilstein J. Nanotechnol. 2024, 15, 1132–1141, doi:10.3762/bjnano.15.92

• electron–hole pairs. Additionally, TiO2/SiNWs offer flexibility, improved bandgap energy, and enhanced light harvesting across a broad spectrum, leading to higher photocatalytic efficiency. Combining SiNWs and TiO2 presents an opportunity to leverage the strengths of both materials while mitigating their

Photocatalytic degradation of methylene blue under visible light by cobalt ferrite nanoparticles/graphene quantum dots

• Vo Chau Ngoc Anh,
• Le Thi Thanh Nhi,
• Le Thi Kim Dung,
• Dang Thi Ngoc Hoa,
• Nguyen Truong Son,
• Nguyen Thi Thao Uyen,
• Nguyen Ngoc Uyen Thu,
• Le Van Thanh Son,
• Le Trung Hieu,
• Tran Ngoc Tuyen and
• Dinh Quang Khieu

Beilstein J. Nanotechnol. 2024, 15, 475–489, doi:10.3762/bjnano.15.43

• that the resulting composite can enhance the absorption capacity [11]. This observation is an agreement with previous works [11]. In addition, a slight shift of the PL emission peak is also observed because of the blue shift in the UV–vis spectrum, which is consistent with their bigger bandgap energy

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

• within the forbidden gap. These states lead to a reduction in bandgap energy and an upward shift of the Fermi level [41][42]. This is the reason behind the observed reduction in bandgap with higher thicknesses (Figure 2b,c) [43]. To probe the Fermi level position, KPFM is a useful tool to acquire

The microstrain-accompanied structural phase transition from h-MoO₃ to α-MoO₃ investigated by in situ X-ray diffraction

• Zeqian Zhang,
• Honglong Shi,
• Boxiang Zhuang,
• Minting Luo and
• Zhenfei Hu

Beilstein J. Nanotechnol. 2023, 14, 692–700, doi:10.3762/bjnano.14.55

• from +2 to +6 [1][2], leading to a range of molybdenum oxides. Molybdenum oxides include the fully stoichiometric MoO3 with a large bandgap above 2.7 eV, the reduced oxides MoO3−x with oxygen vacancies, and the semimetal MoO2. The degree of reduction influences the bandgap energy of molybdenum oxides

Conjugated photothermal materials and structure design for solar steam generation

• Chia-Yang Lin and
• Tsuyoshi Michinobu

Beilstein J. Nanotechnol. 2023, 14, 454–466, doi:10.3762/bjnano.14.36

• semiconductor materials, optical absorption significantly varies with the wavelength, depending on the bandgap energy. When semiconductor materials are irradiated with light, electron–hole pairs with energies close to the bandgap are produced. The excited electrons eventually return to a lower energy state and

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

Bismuth-based nanostructured photocatalysts for the remediation of antibiotics and organic dyes

• Akeem Adeyemi Oladipo and
• Faisal Suleiman Mustafa

Beilstein J. Nanotechnol. 2023, 14, 291–321, doi:10.3762/bjnano.14.26

• ][104][110][144][145][146][147][148][149][150]. Doping reduces the bandgap energy, introduces intermediate energy levels to overcome constraints, creates trap sites to capture photogenerated charge carriers, and increases the absorption of visible light. Additionally, after doping, oxygen vacancies or

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

• transmittance of 94% and increased the bandgap energy from 2.76 to 2.88 eV at 120 mJ. The annealing treatment decreased the resistivity from 15.63 × 10−4 to 1.73 × 10−4 Ω/cm−1. Additionally, the figure of merit of the ITO/Mo structure improved significantly from 6.63 × 10−4 Ω−1 of the as-deposited sample to

• crystalline improvement leads to less light scattering in the metal layer [29][30]. Moreover, laser annealing reduces the defects, including grain boundaries and impurities, reducing light scattering and photon–electron interactions [29][30][31]. The optical bandgap energy Eg of ITO/Mo thin film was studied

• 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

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

• 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

• visible-light range in comparison to that of the remaining samples. To evaluate the optical bandgap energy of TNAs and g-C3N4, Tauc plots were extrapolated in Figure 4b. The bandgap values of TNAs, g-C3N4, and MoS2 were calculated as about 3.15, 2.67, and 1.47 eV, respectively. These results are agreement

• has been demonstrated. The ability to enhance the optical interaction of the heterostructures was presented through the reduction of the bandgap energy. The outstanding application performance of g-C3N4/TNAs and MoS2/TNAs combinations was presented. In detail, the excellent water-splitting ability of

Non-stoichiometric magnetite as catalyst for the photocatalytic degradation of phenol and 2,6-dibromo-4-methylphenol – a new approach in water treatment

• Joanna Kisała,
• Anna Tomaszewska and
• Przemysław Kolek

Beilstein J. Nanotechnol. 2022, 13, 1531–1540, doi:10.3762/bjnano.13.126

• determine x for the catalysts under study (Table 1). The determined x-values indicate that the catalysts were non-stoichiometric magnetites. M1 with a larger grain diameter is less oxidized while M2 is highly oxidized. This is also reflected in the electron bandgap energy. These values show that the tested

• higher than the bandgap energy generates holes and electrons, which, after moving to the catalyst surface, may participate in redox processes. In a basic medium, the photocatalytic process may proceed by oxygen reduction at the surface of the particles (electron transfer only) [37]. A similar electron

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

• nitrogen vacancies and formation of energy sub-bands which help in overall reduction of the bandgap energy (Eg) [14]. At the same time, the incorporation of carbon into the HBN lattice results in the delocalization of electrons with simultaneous reduction in bandgap and is directly dependent upon the

Near-infrared photoactive Ag-Zn-Ga-S-Se quantum dots for high-performance quantum dot-sensitized solar cells

• Roopakala Kottayi,
• Ilangovan Veerappan and
• Ramadasse Sittaramane

Beilstein J. Nanotechnol. 2022, 13, 1337–1344, doi:10.3762/bjnano.13.110

• spectrum of colloidal AZGSSe QDs (Figure 4a) reveals a wide absorption range in the near-infrared (NIR) region. This confirms the NIR photoactive nature of the synthesized QDs. Figure 4b depicts the Tauc plot [30] of the synthesized QDs. From this, the bandgap energy of AZGSSe QDs was found to be 1.37 eV

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

• dimensionality, it was projected that there would be a significant confinement effect and enlarged bandgap energy. Additionally, an upshift of the CB and a downshift of the VB were also measured [48][50]. The preparation process can be used to modify the electrical structure of Bi-based semiconductors. Most Bi

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

• oxide with wide bandgap (3.5–5 eV), high availability, non-toxicity, low cost, and native structural defects [18][19]. The large bandgap energy is the limitation of MgO, reducing the photocatalytic performance and applicability of MgO [20]. Various efforts have been made to enhance the absorption in the

• −1), and M is the molecular weight of NO (g·mol−1). The photon flux in the photocatalytic experiment is 2.72·1019 cm−2·min−1, the irradiation area for the 12 cm diameter petri dish is 113.1 cm2. In addition, the bandgap energy of materials was calculated by using the Tauc and the Kubelka–Munk

• 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

Green synthesis of zinc oxide nanoparticles toward highly efficient photocatalysis and antibacterial application

• Vo Thi Thu Nhu,
• Nguyen Duy Dat,
• Le-Minh Tam and
• Nguyen Hoang Phuong

Beilstein J. Nanotechnol. 2022, 13, 1108–1119, doi:10.3762/bjnano.13.94

• dihydrate and synthesized ZnO NPs with sizes in the range of 9–18 nm. UV–vis DRS spectra of ZnO were shown in Figure 6a. ZnO absorbs light in the ultraviolet region. The bandgap energy of synthesized ZnO was determined by extrapolation of the linear part of the curve (α·hν)2 as a function of photon energy

• (Figure 6b). The bandgap energy of synthesized ZnO was 3.15 eV, which is close to the bandgap value of 3.2 eV of ZnO shown in a previous report [33]. The zeta potential value displays the surface charge and stability of ZnO NPs. In this study, the zeta potential of ZnO NPs was −19 mV (Figure 7

• irradiation by visible and UV light, the MO degradation efficiency by ZnO NPs reached 33.56 and 82.78%, respectively. ZnO has a rather high bandgap energy; therefore, the degradation efficiency of organic substances under visible light is not as high as that under UV light. Maddu et al. [34] studied the