Simple approach for the fabrication of PEDOT-coated Si nanowires

• Mingxuan Zhu,
• Marielle Eyraud,
• Judikael Le Rouzo,
• Nadia Ait Ahmed,
• Florence Boulc’h,
• Claude Alfonso,
• Philippe Knauth and
• François Flory

Beilstein J. Nanotechnol. 2015, 6, 640–650, doi:10.3762/bjnano.6.65

• the transport path along the radial direction of photogenerated carriers to be greatly shortened without sacrificing light absorption [9]. However, the high aspect ratio of SiNWs makes it difficult to realize a radial p–n junction, where each individual Si wire in the array would need to be

• increases from b to d. Clearly, by increasing the tapering duration, the space between wires is increased, the density of wires is reduced, and their top becomes sharper. Spectrophotometric measurements were performed on these samples to determine their light absorption properties (Figure 3). Due to the

Palladium nanoparticles anchored to anatase TiO₂ for enhanced surface plasmon resonance-stimulated, visible-light-driven photocatalytic activity

• Kah Hon Leong,
• Hong Ye Chu,
• Shaliza Ibrahim and
• Pichiah Saravanan

Beilstein J. Nanotechnol. 2015, 6, 428–437, doi:10.3762/bjnano.6.43

• with different amounts of palladium clearly shows the contribution of metallic Pd NPs. Although a small amount of Pd NPs enhanced the visible light absorption, a further increase of the Pd loading leads to an excessive absorption. This induced light scattering phenomena that resulted in deprived

• anchoring of Pd NPs onto the surface of TiO2, and the large size of the Pd NPs contributed to the visible-light absorption. Localized surface plasmon resonance (LSPR) and the formation of a Schottky barrier at the TiO2 interface also occured. The prepared heterogeneous photocatalysts exhibited superior

Tunable white light emission by variation of composition and defects of electrospun Al₂O₃–SiO₂ nanofibers

• Jinyuan Zhou,
• Gengzhi Sun,
• Hao Zhao,
• Xiaojun Pan,
• Zhenxing Zhang,
• Yujun Fu,
• Yanzhe Mao and
• Erqing Xie

Beilstein J. Nanotechnol. 2015, 6, 313–320, doi:10.3762/bjnano.6.29

• . The inset optical photos in (a) and (c) are the corresponding light emission spot of Al6Si4 and Al4Si6 samples, respectively. (d) Energy transfer diagram indicating the mechanism for Al2O3–SiO2 nanocomposite emission. The dashed lines represent light absorption, the solid lines radiative transitions

Tunable light filtering by a Bragg mirror/heavily doped semiconducting nanocrystal composite

• Ilka Kriegel and
• Francesco Scotognella

Beilstein J. Nanotechnol. 2015, 6, 193–200, doi:10.3762/bjnano.6.18

• reversibly tuned by electrochemical post-treatment leading to a switching of the plasma frequency throughout the NIR spectral region [33][36][37]. Taken altogether, the proposed theoretical framework is appropriate to describe the tuning of light absorption with doped semiconductor NCs in a dispersion or in

• carrier density in the heavily doped semiconductor NC component through chemical and electrochemical treatments, ultimately leading to tunable plasmonic light absorption. Illustration of the tunable optical properties of a) a Cu2−xSe NC dispersion and b) an ITO NC film as a function of carrier density NC

Localized surface plasmon resonances in nanostructures to enhance nonlinear vibrational spectroscopies: towards an astonishing molecular sensitivity

• Dan Lis and
• Francesca Cecchet

Beilstein J. Nanotechnol. 2014, 5, 2275–2292, doi:10.3762/bjnano.5.237

• frequencies matching the energy gap between vibrational states (Figure 1). Physically, it corresponds to oscillators presenting a variation of the dipole moment. In fine, the transmitted or reflected beam intensity is reduced because of the light absorption. In spontaneous Raman spectroscopy, a monochromatic

Photodetectors based on carbon nanotubes deposited by using a spray technique on semi-insulating gallium arsenide

• Domenico Melisi,
• Maria Angela Nitti,
• Marco Valentini,
• Antonio Valentini,
• Teresa Ligonzo,
• Giuseppe De Pascali and
• Marianna Ambrico

Beilstein J. Nanotechnol. 2014, 5, 1999–2006, doi:10.3762/bjnano.5.208

• reported for SFS and DFS in Figure 5 and Figure 6 for the visible and the UV range, respectively. The higher QE of SFS with respect to DFS at lower wavelengths in the visible light range (Figure 5) can be attributed to the contribution to the photo-generated charges from the near-band-gap light absorption

Enhanced photocatalytic hydrogen evolution by combining water soluble graphene with cobalt salts

• Jing Wang,
• Ke Feng,
• Hui-Hui Zhang,
• Bin Chen,
• Zhi-Jun Li,
• Qing-Yuan Meng,
• Li-Ping Zhang,
• Chen-Ho Tung and
• Li-Zhu Wu

Beilstein J. Nanotechnol. 2014, 5, 1167–1174, doi:10.3762/bjnano.5.128

• electron-donating ability and less Co(TEOA)22+ catalyst is formed. In a basic solution, the graphene dispersion was more stable and the light absorption of EY is stronger but the concentration of protons is too low. To optimize the hydrogen evolution system, four sets of experiments were carried out

DFT study of binding and electron transfer from colorless aromatic pollutants to a TiO₂ nanocluster: Application to photocatalytic degradation under visible light irradiation

• Corneliu I. Oprea,
• Petre Panait and
• Mihai A. Gîrţu

Beilstein J. Nanotechnol. 2014, 5, 1016–1030, doi:10.3762/bjnano.5.115

• irradiation decreases in the sequence SA > Ph > pHBA > BA. Thus, analyzing the pollutants against some requirements for efficient photocatalytic degradation, we found that BA has no absorption in the visible range even bound to the catalyst. Ph has best light absorption but weakest anchoring, pHBA has very

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

• should be pointed out that TiO2 can only respond to UV light, even metal ion doping can hardly enhance its visible light activity. Sensitization with dyes or nanocrystals is one possible approach to extend the light absorption of TiO2. Sreethawong et al. found that eosin Y-sensitized mesoporous-assembled

• as Cr or/and Ti incorporation in MCM-41. Active visible light absorption sites could be generated in MCM-41 due to transitional metal doping. It was found that the highly dispersed Cr ions within MCM 41 could be easily excited by visible light irradiation due to the electron transfer from O2− to Cr6

• microclusters with exposed {001} facets via a facile and surfactant-free hydrothermal reaction. The light absorption, charge separation and surface reaction were simultaneously optimized through the unique structure assembled from nanosheets, leading to the greatly enhanced photocatalytic activity [49]. Micro

Growth and characterization of CNT–TiO₂ heterostructures

• Yucheng Zhang,
• Ivo Utke,
• Johann Michler,
• Gabriele Ilari,
• Marta D. Rossell and
• Rolf Erni

Beilstein J. Nanotechnol. 2014, 5, 946–955, doi:10.3762/bjnano.5.108

• discovery that with the addition of CNTs, the light absorption of TiO2 can be extended to the visible-light region [8][9][10][11][12][13][14]. This can significantly increase the photocatalytic efficiency. In literature several photocatalysis enhancement mechanisms based on TiO2–CNT have been proposed, as

Optical modeling-assisted characterization of dye-sensitized solar cells using TiO₂ nanotube arrays as photoanodes

• Jung-Ho Yun,
• Il Ku Kim,
• Yun Hau Ng,
• Lianzhou Wang and
• Rose Amal

Beilstein J. Nanotechnol. 2014, 5, 895–902, doi:10.3762/bjnano.5.102

• 3.3 μm long TNT array was around 23% in this wavelength range. The increase in tube lengths to 11.5 and 20.6 μm led to the enhancement of the IPCE values to 57% and 63%, respectively. Below 500 nm the IPCE values were rapidly decreasing due to the reduced light absorption by the reflection effect of

• transfer matrix method (GTMM) has been applied to calculate and analyze the interference effect by multi-layers in solar cells [15]. The optical modeling using GTMM provides reliable information about the spatial distribution of the electric field intensity and the internal light absorption efficiency of

• light has a wavelength of 550 nm, which is a primary light absorption peak of N719 dye, corresponding to the IPCE result in Figure 3. Under the same illumination of 550 nm wavelength, the magnitude of the electric field intensity increased with the increase in the lengths of the TNT. The magnitude of

Enhancement of photocatalytic H₂ evolution of eosin Y-sensitized reduced graphene oxide through a simple photoreaction

• Weiying Zhang,
• Yuexiang Li,
• Shaoqin Peng and
• Xiang Cai

Beilstein J. Nanotechnol. 2014, 5, 801–811, doi:10.3762/bjnano.5.92

• interaction between EY and GO/RGOx, the fluorescence spectra of the mixture of EY and GO or RGOx were measured, as shown in Figure 4. The inset of Figure 4 displays a strong fluorescence peak of EY (about 6.8 × 103 a.u.) at 542 nm. This can be attributed to the large visible light absorption by its conjugated

• 0.7 μmol. This may be due to the deceleration of the light absorption of EY by RGO24, which results in the formation of few photo-excited electrons at low concentrations of dye. When the EY concentration increases to 5.0 × 10−4 mol L−1, more and more EY molecules adsorb at RGO24, which can effectively

• to RGO. Moreover, excess EY in solution may not only screen the light absorption of EY-RGO but also produce self-quenching, which greatly decreases the utilization efficiency of the incident light [20][50]. Thus, the photocatalytic activity decreases at 1.0 × 10−3 mol L−1 EY. Figure 7C shows the

Visible light photooxidative performance of a high-nuclearity molecular bismuth vanadium oxide cluster

• Johannes Tucher and
• Carsten Streb

Beilstein J. Nanotechnol. 2014, 5, 711–716, doi:10.3762/bjnano.5.83

• photocatalysts is a well-established method which gives access to materials for which light absorption, catalytic activity and selectivity can be tuned by structural and chemical modifications [1][2][3][4][5][6]. Prime examples for this approach are molecular metal oxides, so-called polyoxometalates (POMs) [7][8

• nm, making the cluster attractive for visible light absorption. When compared with a prototype pure vanadium oxide cluster such as [H3V10O28]3−, the increase in extinction coefficient and the higher visible light absorption are obvious, see Figure 1. Photooxidative decomposition of the model

• compound features a near-visible LMCT absorption band with ε335 = 15940 M−1 cm−1. In contrast, the pure vanadium oxide cluster [H3V10O28]3− features significantly reduced visible-light absorption (black line). Photooxidative performance of 1 under anaerobic (blue triangles) and aerobic (red circles

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

• conducted direct femtosecond measurements of the electron transfer process from CdS to TiO2 and found that this process could be completed on a time constant of 2 picoseconds, resulting in a significantly slower recombination of the charge carriers generated upon light absorption in CdS [19]. Improved

• 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

• semiconductor family for photocatalytic applications. The synergistic effect of doping and sensitization is also applied to certain wide-bandgap transition metal oxides. It is found that doping with photosensitization can dramatically change the visible-light absorption and significantly enhance the

Effects of the preparation method on the structure and the visible-light photocatalytic activity of Ag₂CrO₄

• Difa Xu,
• Shaowen Cao,
• Jinfeng Zhang,
• Bei Cheng and
• Jiaguo Yu

Beilstein J. Nanotechnol. 2014, 5, 658–666, doi:10.3762/bjnano.5.77

• the smaller particle size, higher surface area, relatively stronger light absorption, and blue-shift absorption edge, which result in the adsorption of more MB molecules, a shorter diffusion process of more photogenerated excitons, and a stronger oxidation ability of the photogenerated holes

• ]. Moreover, there is an obvious blue shift of the absorption edge for the S-M sample, which should be explained in terms of the small size effect [60][61]. In contrast, a weaker light absorption and red shift of the absorption edge are observed for the S-H sample (Figure 5b), because it has the largest

• within 90 min. The S-P and S-H samples exhibit a lower activity with rate constants of 0.020 and 0.012 min−1, respectively. P25 is a mixed-phase TiO2 containing 25% rutile, whit a band gap of 3.0 eV, which results in a weak visible-light absorption up to about 413 nm. Therefore, P25 still shows some

Enhanced photocatalytic activity of Ag–ZnO hybrid plasmonic nanostructures prepared by a facile wet chemical method

• Sini Kuriakose,
• Vandana Choudhary,
• Biswarup Satpati and
• Satyabrata Mohapatra

Beilstein J. Nanotechnol. 2014, 5, 639–650, doi:10.3762/bjnano.5.75

• towards the degradation of MB can be understood as follows: The SPR of Ag nanoparticles helps in extending the light absorption of ZnO from near UV to the visible region, leading to an improved sun-light utilization efficiency. In addition, decoration with Ag nanoparticles significantly improves the

High activity of Ag-doped Cd_0.1Zn_0.9S photocatalyst prepared by the hydrothermal method for hydrogen production under visible-light irradiation

• Leny Yuliati,
• Melody Kimi and
• Mustaffa Shamsuddin

Beilstein J. Nanotechnol. 2014, 5, 587–595, doi:10.3762/bjnano.5.69

• optimum amount of Ag doping showed the highest hydrogen production rate of 3.91 mmol/h, which was 1.7 times higher than that of undoped Cd0.1Zn0.9S. With the Ag doping, a red shift in the optical response was observed, leading to a larger portion of the visible light absorption than that of without doping

• ], and Sr [17] has been a good attempt to increase the visible-light absorption of the Cd1−xZnxS photocatalyst. The use of Ag species as a good dopant for various types of photocatalysts has been also reported [18][19][20], including its use to modify Cd1−xZnxS [21][22][23]. Cd1−xZnxS modified by Ag2S

Artificial sunlight and ultraviolet light induced photo-epoxidation of propylene over V-Ti/MCM-41 photocatalyst

• Van-Huy Nguyen,
• Shawn D. Lin,
• Jeffrey Chi-Sheng Wu and
• Hsunling Bai

Beilstein J. Nanotechnol. 2014, 5, 566–576, doi:10.3762/bjnano.5.67

• used to verify the crystalline structure of the photocatalyst. Diffraction peaks were assigned by comparison to known crystalline phases. The light absorption of the photocatalyst was characterized by ultraviolet–visible light spectroscopy (Varian Cary-100). The X-ray absorption near edge spectroscopy

Mesoporous cerium oxide nanospheres for the visible-light driven photocatalytic degradation of dyes

• Subas K. Muduli,
• Songling Wang,
• Shi Chen,
• Chin Fan Ng,
• Cheng Hon Alfred Huan,
• Tze Chien Sum and
• Han Sen Soo

Beilstein J. Nanotechnol. 2014, 5, 517–523, doi:10.3762/bjnano.5.60

• transformation) of the cerium oxide nanospheres, CeO2 (commercially available 7 nm) nanopowder, and TiO2 (commercially available Degussa P25) nanoparticles are illustrated in Figure 2a. As expected, the cerium oxide sample displayed stronger visible light absorption than both commercially available 7 nm CeO2 and

• enhanced visible light absorption has been exploited for driving the photocatalytic degradation of RhB in aqueous solutions (vide infra). The transmission electron microscopy (TEM) images of the cerium oxide sample supported the mesoporous nature and nanosphere morphology of the material (Figure 3a). The

• the preparation of the earth-abundant, relatively affordable, mixed valence cerium oxide. The cerium oxide has been characterized with a suite of structural, spectroscopic, and electron microscopy techniques, confirming the high surface area, mesoporous nature, and visible-light absorption properties

One-step synthesis of high quality kesterite Cu₂ZnSnS₄ nanocrystals – a hydrothermal approach

• Vincent Tiing Tiong,
• John Bell and
• Hongxia Wang

Beilstein J. Nanotechnol. 2014, 5, 438–446, doi:10.3762/bjnano.5.51

• was formed by the diffusion of Zn2+ and Sn4+ cations to the lattice of Cu2−xS during the hydrothermal reaction. The as-synthesized CZTS nanocrystals exhibited strong light absorption over the range of wavelength beyond 1000 nm. The band gap of the material was determined to be 1.51 eV, which is

• has a theoretical band gap of 1.5 eV and has high light absorption coefficient (>104 cm−1) in the range of visible and near infrared irradiation of solar spectrum [2][3][4]. Shockley–Queisser balanced calculations have predicted that the theoretical efficiency of PVs using light absorbers like CZTS is

• above analysis, a schematics showing the formation mechanism for CZTS compound in the hydrothermal reaction is shown in Figure 8. The UV–visible spectra of the hydrothermal samples synthesized at different reaction time are shown in Figure 9. It is found that the onset for light absorption of the

Atomic layer deposition, a unique method for the preparation of energy conversion devices

• Julien Bachmann

Beilstein J. Nanotechnol. 2014, 5, 245–248, doi:10.3762/bjnano.5.26

• which can be performed by ALD materials may be rationalized if a few common themes are recognized, which run like a common thread through this Thematic Series: ALD for a direct device function, such as light absorption in solar cells, ion conduction and electrocatalysis in fuel cells, or lithium uptake

Study of mesoporous CdS-quantum-dot-sensitized TiO₂ films by using X-ray photoelectron spectroscopy and AFM

• Mohamed N. Ghazzal,
• Robert Wojcieszak,
• Gijo Raj and
• Eric M. Gaigneaux

Beilstein J. Nanotechnol. 2014, 5, 68–76, doi:10.3762/bjnano.5.6

• increase in the absorbance observed for successive deposition cycles confirms the growth of the CdS particles. No significant increase in the absorbance was observed after 15 deposition cycles. The band gap of the films was determined by extrapolating the fitting line of the onset light absorption to zero

Many-body effects in semiconducting single-wall silicon nanotubes

• Wei Wei and
• Timo Jacob

Beilstein J. Nanotechnol. 2014, 5, 19–25, doi:10.3762/bjnano.5.2

• excitation and optical absorption properties. It is well-known that density functional theory (DFT) often fails in describing the properties of light absorption. This process requires a description of two-particle properties, which certainly goes beyond single-electron excitations that can be described at

Preparation of NiS/ZnIn₂S₄ as a superior photocatalyst for hydrogen evolution under visible light irradiation

• Liang Wei,
• Yongjuan Chen,
• Jialin Zhao and
• Zhaohui Li

Beilstein J. Nanotechnol. 2013, 4, 949–955, doi:10.3762/bjnano.4.107

• visible light. ZnIn2S4 is a ternary chalcogenide with a suitable band gap (2.34–2.48 eV) well corresponding to the visible light absorption. ZnIn2S4 exhibits two distinct polymorphs based on cubic and hexagonal lattices [16], which can be controlled synthesized via a facile hydrothermal method using

Template based precursor route for the synthesis of CuInSe₂ nanorod arrays for potential solar cell applications

• Mikhail Pashchanka,
• Jonas Bang,
• Niklas S. A. Gora,
• Ildiko Balog,
• Rudolf C. Hoffmann and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2013, 4, 868–874, doi:10.3762/bjnano.4.98

• purity and crystallinity, and a stoichiometric composition of the CISe ternary semiconductor compound. Keywords: CIS; light absorption; nanocasting; nanorod arrays; precursor synthesis; Introduction Polycrystalline heterojunction solar cells with a columnar morphology of the photovoltaic active layer

• unique ability for independent adjustment of light absorption (by nanowire length) and charge separation (by nanowire diameter). Nanowire-based photovoltaic layers will allow the fabrication of low-cost small size energy devices with economical use of materials. Very recently, Schoen et al. reported the

• the elements are present in the correct stoichiometry [14]. Secondly, the method allows to lower the conversion temperature and to reduce the particle size. Thus, the products usually contain small particles of large surface area, which is favourable for visible light absorption. Finally, the