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

• monolayered Ge2Se2. The easy fabrication, structural stability, and proper band alignment with the absorber material make it a promising hole transport layer (HTL) in the proposed solar cell. The proposed solar cell is a low-cost, environmentally friendly, scalable Perovskite solar cell (PSC), with Ge2Se2 as

• offset and ease of synthesis. The front and back contacts are supposed to be ohmic and are made of silver (Ag) to maintain proper band alignment and reduce the band offset. It has been reported that tuning the CBM and VBM positions to keep a low band offset leads to superior device performance. Figure 6b

• with DFT-post processing; (b) calculation of the optical behavior based on the non-equilibrium Green’s function (NEGF) and the Kubo–Greenwood approaches. Fifth step – device design, simulation, and optimization: After proper band alignment and suitable material choices for the transport and active

Interface properties of nanostructured carbon-coated biological implants: an overview

• Mattia Bartoli,
• Francesca Cardano,
• Erik Piatti,
• Stefania Lettieri,
• Andrea Fin and
• Alberto Tagliaferro

Beilstein J. Nanotechnol. 2024, 15, 1041–1053, doi:10.3762/bjnano.15.85

• another (inter-layer transport) and is the source of the large anisotropy typically displayed between in-plane and out-of-plane carrier mobilities [42]. Carrier injection is usually determined by energy band alignment and interface transparency, and it is limited by the number of available conduction

Intermixing of MoS₂ and WS₂ photocatalysts toward methylene blue photodegradation

• Maryam Al Qaydi,
• Nitul S. Rajput,
• Michael Lejeune,
• Abdellatif Bouchalkha,
• Mimoun El Marssi,
• Steevy Cordette,
• Chaouki Kasmi and
• Mustapha Jouiad

Beilstein J. Nanotechnol. 2024, 15, 817–829, doi:10.3762/bjnano.15.68

• visible light excites electrons in WS2 they transition into the CB of MoS2 due to band alignment. These photoexcited electrons then move from the CB of WS2 to MoS2, generating radical electrons that subsequently react with oxygen groups. Simultaneously, photoexcited holes spontaneously migrate from the

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

• carrier separation, high photo-transporter mobility, appropriate physical and chemical properties, sufficient band alignment to meet the kinetic requirements of the target reaction, and anti-corrosion stability in reactive environments [18][19][20]. Figure 1 depicts the mechanism of the photocatalyst. In

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

• oxidation and breakdown of the pollutant during the photocatalytic reaction. One of the most popular ways to create an effective heterojunction structure is by combining two semiconductors with matching band alignment. When it comes to understanding the mechanisms behind the enhanced photocatalytic

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

• (+1.75 eV) is more negative than that of H2O/•OH (+2.40 eV), reducing the photocatalytic efficiency [16][17]. A well-known approach for overcoming this problem in order to achieve increased photocatalytic performance is to couple two semiconductors with optimal band alignment. MgO is an alkaline metal

Nickel nanoparticle-decorated reduced graphene oxide/WO₃ nanocomposite – a promising candidate for gas sensing

• Ilka Simon,
• Alexandr Savitsky,
• Rolf Mülhaupt,
• Vladimir Pankov and
• Christoph Janiak

Beilstein J. Nanotechnol. 2021, 12, 343–353, doi:10.3762/bjnano.12.28

• band alignment between the semiconductor and rGO, the electron acceptor functionalization of the analyzed gas, and the p-type conductivity of the rGO. Thus, the electron-depleted WO3 surface is more sensitive to the adsorption of acetone molecules and the transition of electrons from the adsorbed gas

Monolayers of MoS₂ on Ag(111) as decoupling layers for organic molecules: resolution of electronic and vibronic states of TCNQ

• Asieh Yousofnejad,
• Gaël Reecht,
• Nils Krane,
• Christian Lotze and
• Katharina J. Franke

Beilstein J. Nanotechnol. 2020, 11, 1062–1071, doi:10.3762/bjnano.11.91

• and K′ by circularly polarized light [32]. The potential as decoupling layer for molecules may become even more appealing by the fact that monolayers of transition metal dichalcogenides can be grown in situ on different metal surfaces, where the precise hybridization and band alignment depend on the

First principles modeling of pure black phosphorus devices under pressure

• Ximing Rong,
• Zhizhou Yu,
• Zewen Wu,
• Junjun Li,
• Bin Wang and
• Yin Wang

Beilstein J. Nanotechnol. 2019, 10, 1943–1951, doi:10.3762/bjnano.10.190

• set of parameters based on the results from the empirical Wentzel–Kramers–Brillouin method, which provides an effortless approximation to quantitatively predict the pressure-related behaviors of large pure BP devices. Keywords: band alignment; black phosphorus; first principles calculation; pressure

• introduce the first principles modeling methods. In section “Results and Discussion”, we present the numerical results and physical analysis of the BP devices including pressure-dependent mechanical and electric properties, quantum transport and band alignment. In addition, the conductance of the BP devices

• . More importantly, the conductance is not sensitive to the pressure when RC < 15% for the fully relaxed zigzag BP device, while it decreases rapidly for the fully relaxed armchair BP device. Band alignment analysis and WKB fitting The different behavior of conductance as a function of the pressure for

High-temperature resistive gas sensors based on ZnO/SiC nanocomposites

• Vadim B. Platonov,
• Marina N. Rumyantseva,
• Alexander S. Frolov,
• Alexey D. Yapryntsev and
• Alexander M. Gaskov

Beilstein J. Nanotechnol. 2019, 10, 1537–1547, doi:10.3762/bjnano.10.151

• formation of n–n heterocontacts at the ZnO/SiC interface [35]. According to a previous report [36] the conduction band minimum (CBM) of n-type ZnO lies 0.4 eV lower than the CBM of n-type SiC. The calculated band alignment of the wurtzite (2H) ZnO and SiC phases is presented in previous reports [37][38

• ]. Taking into account the difference in the band gap (Eg) of 2H-SiC (Eg = 3.3 eV [39]) and 3C-SiC (Eg = 2.36 eV [40]) polytypes, and assuming that the position of the valence band for these polytypes does not vary significantly, we constructed a diagram of the band alignment for ZnO and 3C-SiC phases

• = 30% (b,d). Insets: Sensor response dependence on SiC content in nanocomposites. Temperature dependence of the sensor response of ZnO nanofibers and ZnO/SiC nanocomposites towards 20 ppm NH3 (a,b) and 20 ppm CO (c,d) in dry air RH25 = 0% (a,c) and at relative humidity RH25 = 30% (b,d). Estimated band

Electronic and magnetic properties of doped black phosphorene with concentration dependence

• Ke Wang,
• Hai Wang,
• Min Zhang,
• Yan Liu and
• Wei Zhao

Beilstein J. Nanotechnol. 2019, 10, 993–1001, doi:10.3762/bjnano.10.100

• isosurfaces are separated by ±0.04 e/Å3. Top view and side view of the physical model of doped monolayer phosphorene. Band alignment of phosphorene calculated by using (a) the GGA of PBEsol and (b) HSE06. The inset shows the path in the Brillouin zone. The Fermi level is shifted to zero. Acknowledgements

Synthesis of novel C-doped g-C₃N₄ nanosheets coupled with CdIn₂S₄ for enhanced photocatalytic hydrogen evolution

• Jingshuai Chen,
• Chang-Jie Mao,
• Helin Niu and
• Ji-Ming Song

Beilstein J. Nanotechnol. 2019, 10, 912–921, doi:10.3762/bjnano.10.92

• visible-light range. This phenomenon may be ascribed to the introduction of CdIn2S4 with slightly narrower bandgaps and the band alignment of the two materials. Furthermore, the introduction of CdIn2S4 into the matrix of CCN has an important impact on the optical absorption properties of CISCCN

Hierarchical heterostructures of Bi₂MoO₆ microflowers decorated with Ag₂CO₃ nanoparticles for efficient visible-light-driven photocatalytic removal of toxic pollutants

• Shijie Li,
• Wei Jiang,
• Shiwei Hu,
• Yu Liu,
• Yanping Liu,
• Kaibing Xu and
• Jianshe Liu

Beilstein J. Nanotechnol. 2018, 9, 2297–2305, doi:10.3762/bjnano.9.214

• attributed to the high charge-separation capacity, which results from the matched band alignment of the two components. The cycling experiments showed a good durability of Ag2CO3/Bi2MoO6. Holes were found to be the dominant active species accounting for the pollutant degradation. This compound is a promising

Lead-free hybrid perovskites for photovoltaics

• Oleksandr Stroyuk

Beilstein J. Nanotechnol. 2018, 9, 2209–2235, doi:10.3762/bjnano.9.207

The role of the Ge mole fraction in improving the performance of a nanoscale junctionless tunneling FET: concept and scaling capability

• Hichem Ferhati,
• Fayçal Djeffal and
• Toufik Bentrcia

Beilstein J. Nanotechnol. 2018, 9, 1856–1862, doi:10.3762/bjnano.9.177

• barrier height at the source–channel junction decreases and a higher tunneling current can be generated when the band alignment at the junction is satisfied. In addition, Figure 4 shows the complex subthreshold behavior. The Ge mole fraction induces a highly non-linear behavior of the swing factor as it

Cr(VI) remediation from aqueous environment through modified-TiO₂-mediated photocatalytic reduction

• Rashmi Acharya,
• Brundabana Naik and
• Kulamani Parida

Beilstein J. Nanotechnol. 2018, 9, 1448–1470, doi:10.3762/bjnano.9.137

• described by the Langmuir–Hinshelwood model [182]. The heterosystem CuCo2O4/TiO2 for the removal of Cr(VI) by photocatalytic reduction under visible light has been reported by Kebir et al. [183]. The synergetic effect of adsorption and photocatalytic reduction with proper band alignment are attributed to

Filled and empty states of Zn-TPP films deposited on Fe(001)-p(1×1)O

• Gianlorenzo Bussetti,
• Alberto Calloni,
• Rossella Yivlialin,
• Andrea Picone,
• Federico Bottegoni and
• Marco Finazzi

Beilstein J. Nanotechnol. 2016, 7, 1527–1531, doi:10.3762/bjnano.7.146

• the molecular packing could influence the energy levels of the film. However, the band alignment at the molecule/substrate interface is mainly due to a charge transfer between the organic layers and the substrate and a consequent modification of the electron density, as reported in the literature [18

• respect to the pristine Fe(001)-p(1×1)O substrate. The determination of such an interface dipole, its direction with respect to the sample surface, and its dependence on the porphyrin film thickness are important in view of possible applications in electronic device prototypes. In such devices, the band

• alignment between molecular levels and substrate bands plays a key role in the transport properties. Results and Discussion From a technological point of view, the 1 monolayer (ML) thick sample is the most interesting and appealing, due to its ordered (5 × 5) reconstruction [10] that can be exploited (i) as

High-resolution noncontact AFM and Kelvin probe force microscopy investigations of self-assembled photovoltaic donor–acceptor dyads

• Benjamin Grévin,
• Pierre-Olivier Schwartz,
• Laure Biniek,
• Martin Brinkmann,
• Nicolas Leclerc,
• Elena Zaborova and
• Stéphane Méry

Beilstein J. Nanotechnol. 2016, 7, 799–808, doi:10.3762/bjnano.7.71

• a flat band alignment. Under illumination, the holes quasi-Fermi level remains aligned with the Fermi level of the grounded substrate, while the quasi-Fermi level of the electrons is located near the lowest unoccupied orbital level (LUMO) of the acceptor units. As a consequence, the local vacuum

• SPV is more negative. The black dotted squares indicate the location corresponding to the high-resolution images (shown later in Figure 9a,b). Schematic representation of an idealized D–A network and its band alignment with respect to the substrate. Here, we assume a Fermi level pinning of the donor

• blocks after charge transfer to the substrate (resulting in the existence of an interface dipole, Δ), and a flat band alignment (in dark) of the acceptor segments. Under illumination, the local vacuum level (EVac) remains constant over the donor segments while it is shifted upward over the acceptor

Synthesis and applications of carbon nanomaterials for energy generation and storage

• Marco Notarianni,
• Jinzhang Liu,
• Kristy Vernon and
• Nunzio Motta

Beilstein J. Nanotechnol. 2016, 7, 149–196, doi:10.3762/bjnano.7.17

Functionalized nanostructures for enhanced photocatalytic performance under solar light

• Liejin Guo,
• Dengwei Jing,
• Maochang Liu,
• Yubin Chen,
• Shaohua Shen,
• Jinwen Shi and
• Kai Zhang

Beilstein J. Nanotechnol. 2014, 5, 994–1004, doi:10.3762/bjnano.5.113

• nanoscale, i.e., materials with the same compositions but different phases with certain band alignment. We conclude this review with perspectives on nanostructure design that might direct future research of this technology. Keywords: functionalized nanostructures; hydrogen; photocatalysis; photocatalytic

• with well-tailored band alignment provides a powerful means to the improvement of the photocatalytic activity. In the process of our study, we have also paid special attention on the nanoscale control of the material morphology and construction of functionalized nanostructures to promote charge

• junction-free semiconductors [66]. Depending on the band gaps and the electronic affinity of semiconductors, semiconductor heterostructures can be divided into three different cases: type-I, type-II and type-III band alignment [67]. In a type-II band alignment, the band offsets in the conduction and

Biomolecule-assisted synthesis of carbon nitride and sulfur-doped carbon nitride heterojunction nanosheets: An efficient heterojunction photocatalyst for photoelectrochemical applications

• Hua Bing Tao,
• Hong Bin Yang,
• Jiazang Chen,
• Jianwei Miao and
• Bin Liu

Beilstein J. Nanotechnol. 2014, 5, 770–777, doi:10.3762/bjnano.5.89

• ). This type-II band alignment means that once CN and CNS are electronically coupled, a well-matched band structure for charge separation will be formed. In this case, the photogenerated electrons are transferred from CN to CNS, while the photogenerated holes are transferred from CNS to CN, leading to an

• photoelectrode, which can be attributed to the large contact area between the CN/CNS photoelectrode and the electrolyte as well as an appropriate band alignment of the CN/CNS interface. It has been well-established that photocurrent is generated because of the diffusion of photogenerated electrons to the back

Nanostructure sensitization of transition metal oxides for visible-light photocatalysis

• Hongjun Chen and
• Lianzhou Wang

Beilstein J. Nanotechnol. 2014, 5, 696–710, doi:10.3762/bjnano.5.82

• the band alignment between CdS and CdSe, the co-sensitized ZnO nanowire arrayed photoanode exhibited almost the entire visible-light absorption and fast electron transfer from CdSe quantum dots to ZnO nanowires and thereby the IPCE value can reach 45% at 0 V vs Ag/AgCl, as demonstrated in Figure 4c

Synthesis of indium oxi-sulfide films by atomic layer deposition: The essential role of plasma enhancement

• Cathy Bugot,
• Nathanaëlle Schneider,
• Daniel Lincot and
• Frédérique Donsanti

Beilstein J. Nanotechnol. 2013, 4, 750–757, doi:10.3762/bjnano.4.85

• of their properties [13][14][15]. It is therefore a suitable technique for the deposition of buffer layers. Platzer-Björkman et al. have used ALD to improve the energy-band alignment between the CIGS and the front electrode by controlling the oxygen concentration in Zn(S,O) buffer layers [4][16

Low-temperature synthesis of carbon nanotubes on indium tin oxide electrodes for organic solar cells

• Andrea Capasso,
• Luigi Salamandra,
• Aldo Di Carlo,
• John M. Bell and
• Nunzio Motta

Beilstein J. Nanotechnol. 2012, 3, 524–532, doi:10.3762/bjnano.3.60

• states of ITO–CNT lying lower than those of ITO. A similar kind of band alignment is almost achieved in the standard cell architecture by the insertion of a layer of poly(3,4-ethylene dioxythiophene):(polystyrene sulfonic acid) (PEDOT:PSS). This polymer is used to improve the contact (and reduce the

Dense lying self-organized GaAsSb quantum dots on GaAs for efficient lasers

• Thomas H. Loeber,
• Dirk Hoffmann and
• Henning Fouckhardt

Beilstein J. Nanotechnol. 2011, 2, 333–338, doi:10.3762/bjnano.2.39

• (SK) growth, depending on the precise control of the Sb/Ga V/III flux ratio, coverage, and growth temperature. Furthermore these parameters influence dot shape, size and density. The staggered (type-II) band alignment with a large valence band offset provides hole confinement. The electronic states