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

• : graphitic carbon nitride (g-C3N4); heterojunction; photoelectrochemical; photocatalysis; sulfur doping; Introduction Over the past few years, graphitic carbon nitride (CN) has attracted significant research attention in visible-light-driven photocatalysis because of its unique physical and chemical

• different light source and the EQE spectra. Figure 6c exhibits the photoresponse of CN, CNS and CN/CNS under different light sources. It can be observed that the photocurrent can be reproducibly produced under AM 1.5G simulated sunlight or visible light (λ > 420 nm) with the same trend following the order

• bias vs Ag/AgCl under simulated sunlight (AM 1.5, 100 mW/cm2) and visible light (λ > 420 nm). (d) External quantum efficiency (EQE) of CN, CNS and CN/CNS photoelectrodes. Supporting Information Supporting Information File 50: Additional experimental data. Acknowledgements The authors acknowledge

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

• Johannes Tucher Carsten Streb Ulm University, Institute of Inorganic Chemistry I, Albert-Einstein-Allee 11, 89081 Ulm, Germany 10.3762/bjnano.5.83 Abstract The visible light photooxidative performance of a new high-nuclearity molecular bismuth vanadium oxide cluster, H3[{Bi(dmso)3}4V13O40], is

• oxidant. Trapping experiments using ethanol as a hydroxyl radical scavenger show significantly decreased photocatalytic substrate oxidation in the presence of EtOH. Photocatalytic performance analyses using monochromatic visible light irradiation show that the quantum efficiency Φ for indigo

• , olefins and others [1][2][3][14]. However, as POMs often only absorb light in the UV range, little is known about the visible-light photocatalytic activity of POMs [5][15]. One means of addressing this challenge is to tune the cluster structure and reactivity by incorporation of a reactive metal site into

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

• Hongjun Chen Lianzhou Wang Nanomaterials Centre, School of Chemical Engineering, The University of Queensland, St. Lucia, Brisbane, QLD, 4072, Australia 10.3762/bjnano.5.82 Abstract To better utilize the sunlight for efficient solar energy conversion, the research on visible-light active

• photocatalysts has recently attracted a lot of interest. The photosensitization of transition metal oxides is a promising approach for achieving effective visible-light photocatalysis. This review article primarily discusses the recent progress in the realm of a variety of nanostructured photosensitizers such as

• quantum dots, plasmonic metal nanostructures, and carbon nanostructures for coupling with wide-bandgap transition metal oxides to design better visible-light active photocatalysts. The underlying mechanisms of the composite photocatalysts, e.g., the light-induced charge separation and the subsequent

A visible-light-driven composite photocatalyst of TiO₂ nanotube arrays and graphene quantum dots

• Donald K. L. Chan,
• Po Ling Cheung and
• Jimmy C. Yu

Beilstein J. Nanotechnol. 2014, 5, 689–695, doi:10.3762/bjnano.5.81

• incorporation of graphene quantum dots could extend the photo-response of the nanotubes to the visible-light range. Graphene quantum dot-sensitized TiO2 nanotube arrays were synthesized by covalently coupling these two materials. The product was characterized by Fourier-transform infrared spectrometry (FTIR

• have been developed to achieve photoresponse of TiO2-based catalysts towards visible light, for example, doping with metal or non-metal [7][17][18][19][20], coupling with other semiconductor materials to form composite catalysts [4][21][22][23][24]. Two-dimensional graphene has attracted immense

• visible-light-driven photocatalysis [35][36]. Very recently, the combination of GQDs with CdS-modified TNAs was reported for photoelectrochemical hydrogen production. However, GQDs did not enhance the activity of bare TNAs in the study [37]. GQDs have also been chemically coupled with ZnO nanowires for

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

• 10.3762/bjnano.5.77 Abstract Silver chromate (Ag2CrO4) photocatalysts are prepared by microemulsion, precipitation, and hydrothermal methods, in order to investigate the effect of preparation methods on the structure and the visible-light photocatalytic activity. It is found that the photocatalytic

• activity of the prepared Ag2CrO4was highly dependent on the preparation methods. The sample prepared by microemulsion method exhibits the highest photocatalytic efficiency on the degradation of methylene blue (MB) under visible-light irradiation. The enhanced photocatalytic activity could be ascribed to

• ; photocatalytic activity; silver chromate; visible-light-driven; Introduction Semiconductor photocatalysis has been considered as a potential solution to the worldwide energy shortage and for counteracting environmental degradation [1][2][3][4][5]. Numerous efforts have been made to develop efficient and stable

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

• visible region by controlling their size, shape, inter-particle spacing and surrounding medium [25]. In case of ZnO modified with noble metal nanoparticles, LSPR absorption can lead to enhanced utilization of UV–visible light as compared to pure ZnO [26][27][28]. Silver nanoparticles decorated ZnO

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

• activity of Cd0.1Zn0.9S was studied for the hydrogen production from water reduction under visible light irradiation. Results: Compared to the series prepared by the co-precipitation method, samples prepared by the hydrothermal method performed with a better photocatalytic activity. The sample with the

• 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

• . In addition to the larger absorption in the visible-light region, the increase in photocatalytic activity of samples with Ag doping may also come from the Ag species facilitating electron–hole separation. Conclusion: This study demonstrated that Ag doping is a promising way to enhance the activity of

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

• received much attention. In this section, we examined the photo-epoxidation of propylene over V-Ti/MCM-41 by utilizing UV-visible light (without an AM1.5G filter) and artificial sunlight (with an AM1.5G filter). With UV–visible light, the C3H6 consumption rate and the PO formation rate with time on stream

• photocatalytic epoxidation of propylene. Both of UV–visible light and artificial sunlight show a similar and stable product distribution (Figure 5b and Figure 6b). The use of AM1.5G filter decreased the photo-activity but similar trends in PO formation rate and C3H6 consumption rate with time on stream are also

• lower cut-off wavelength of irradiation light (260 nm for UV, 200 nm for visible light and 310 nm for artificial light) to the cut-off absorbance of the catalyst (380 nm). The ratio of the integrated absorbance over the filtered range of the light source to the total absorption capacity is defined as

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

• photoelectron and UV–vis spectroscopy, and transmission electron microscopy. Together with N2 sorption experiments, the data confirms that the new cerium oxide material is mesoporous and absorbs visible light. The photocatalytic degradation of rhodamin B is investigated with a series of radical scavengers

• , suggesting that the mechanism of photocatalytic activity under visible-light irradiation involves predominantly hydroxyl radicals as the active species. Keywords: cerium oxide; dye degradation; mesoporous; photocatalysis; visible light; Introduction The degradation of organic pollutants by affordable and

• semiconductors have been explored for the visible-light driven photocatalytic degradation of pollutants and microbes, such as bismuth oxides [5][6] and cerium oxides [12][13]. CeO2 specifically has been applied in a number of sustainable energy applications lately, including oxidative catalysis, hydrogen storage

Encapsulation of nanoparticles into single-crystal ZnO nanorods and microrods

• Jinzhang Liu,
• Marco Notarianni,
• Llew Rintoul and
• Nunzio Motta

Beilstein J. Nanotechnol. 2014, 5, 485–493, doi:10.3762/bjnano.5.56

• to produce red luminescence. ZnO nanorod is transparent to visible light and emissions from NDs can transmit into ZnO nano/microrod to undergo multiple reflections. ZnO is a birefringent crystal with a refractive index of about 2.0 in the visible range, indicating the total refraction angle of light

Dye-sensitized Pt@TiO₂ core–shell nanostructures for the efficient photocatalytic generation of hydrogen

• Jun Fang,
• Lisha Yin,
• Shaowen Cao,
• Yusen Liao and
• Can Xue

Beilstein J. Nanotechnol. 2014, 5, 360–364, doi:10.3762/bjnano.5.41

• hydrothermal method. The dye-sensitization of these Pt@TiO2 core–shell structures allows for a high photocatalytic activity for the generation of hydrogen from proton reduction under visible-light irradiation. When the dyes and TiO2 were co-excited through the combination of two irradiation beams with

• ], TiO2 has received extensive attention as one of the promising semiconductor photocatalysts, because of its high chemical stability, low cost and non-toxicity [2][3][4][5]. However, it suffers from the wide band gap (3.2–3.4 eV), which restricts the utilization of visible light, and the high

• noble metal (e.g., Pt) nanoparticles as co-catalysts that can act as electron-sinks to achieve effective charge separation on TiO2 [7][8][9][10][11]. Dye-sensitization has been widely used to enable visible light harvesting by wide band gap semiconductors. Since the seminal work reported by O’Regan and

Noncontact atomic force microscopy II

• Mehmet Z. Baykara and
• Udo D. Schwarz

Beilstein J. Nanotechnol. 2014, 5, 289–290, doi:10.3762/bjnano.5.31

• needed. As such, breaking the resolution limit associated with the wavelength of visible light employed in traditional optical microscopy has been a long-standing dream of scientists around the world. This goal was finally reached in the early 1980s with the invention of the scanning tunneling microscope

Synthesis of embedded Au nanostructures by ion irradiation: influence of ion induced viscous flow and sputtering

• Udai B. Singh,
• D. C. Agarwal,
• S. A. Khan,
• S. Mohapatra,
• H. Amekura,
• D. P. Datta,
• Ajay Kumar,
• R. K. Choudhury,
• T. K. Chan,
• Thomas Osipowicz and
• D. K. Avasthi

Beilstein J. Nanotechnol. 2014, 5, 105–110, doi:10.3762/bjnano.5.10

• Au nanoparticles into the glass substrate. Keywords: embedded nanoparticles; ion beam irradiation; recoil implantation; Introduction Noble-metal nanoparticles (NPs) are of great interest due to their large surface-to-volume ratio and their enhanced absorption of visible light. The shape- and size

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

• photosensitized solar cells with high quantum yields [1][2][3][4] and the photocatalytic degradation of pollutants [5][6]. CdS, currently used as an efficient visible-light sensitizer, is a semiconductor that possesses a small band gap (2.4 eV) and suitable potential energies. The electron transfer between QDs

Dye-doped spheres with plasmonic semi-shells: Lasing modes and scattering at realistic gain levels

• Nikita Arnold,
• Boyang Ding,
• Calin Hrelescu and
• Thomas A. Klar

Beilstein J. Nanotechnol. 2013, 4, 974–987, doi:10.3762/bjnano.4.110

• . Realistic modeling of 3D plasmonic structures with gain in the visible-light range is non-trivial and requires certain care. As mentioned before, semi-shell structures possess many multipolar eigenmodes that are located closely together in frequency space [11], and many of the modes are easily overlooked

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

• for hydrogen evolution under visible light irradiation was also investigated. It was found that the photocatalytic hydrogen evolution activity over hexagonal ZnIn2S4 can be significantly increased by loading NiS as a co-catalyst. The formation of a good junction between ZnIn2S4 and NiS via the two

• loading amount of 0.5 wt %. This work demonstrates a high potential of the developing of environmental friendly, cheap noble-metal-free co-catalyst for semiconductor-based photocatalytic hydrogen evolution. Keywords: co-catalyst; hydrogen evolution; NiS; photocatalytic; photocatalysis; visible light

• 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

Challenges in realizing ultraflat materials surfaces

• Takashi Yatsui,
• Wataru Nomura,
• Fabrice Stehlin,
• Olivier Soppera,
• Makoto Naruse and
• Motoichi Ohtsu

Beilstein J. Nanotechnol. 2013, 4, 875–885, doi:10.3762/bjnano.4.99

• to fabricate structures of several tens of nanometres in size by introducing near fields with the use of a visible light source [18]. Such advances can lead to the realization of systems that do not require EUV light sources, which are currently of limited practical use in industry because the

• ], photolithography [24], and visible-light water splitting [25], as well as studies on photovoltaic devices [26] and energy up-conversion devices [27]. The efficiency of energy up-conversion by using DPP is reported to be more than three-fold higher than that of up-conversion by using conventional two-photon

• conventional deposition techniques is impossible. To overcome this difficulty, Al2O3 nanoparticles were deposited under illumination with visible light from a CW laser (λ = 473 nm; power density 2.7 W·cm−2) with a wavelength longer than that of the absorption band edge of Al2O3 (λab = 260 nm) [49]. This

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

• 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

Controlled synthesis and tunable properties of ultrathin silica nanotubes through spontaneous polycondensation on polyamine fibrils

• Jian-Jun Yuan,
• Pei-Xin Zhu,
• Daisuke Noda and
• Ren-Hua Jin

Beilstein J. Nanotechnol. 2013, 4, 793–804, doi:10.3762/bjnano.4.90

• porous structure can be, after annealing, used as material, which emits visible light [41][42][43][44]. Although the reason of the silica photoluminescence is not clear, it is mainly attributed to the formation of oxygen defects on the SiO2 framework [44]. To examine the photoluminescence properties, the

• LPEI@silica hybrid nanostructures (nanotubes and nanoribbons, synthetic conditions given in Figure 1) were calcined at 1000 °C under N2 atmosphere. In general, the silica structures prepared from sol–gel procedures emit visible light with wavelengths smaller than 500 nm. However, as shown in Figure 8

• very mild silicification conditions (aqueous media, room-temperature and high efficiency), which could allow for an easy scale-up of silica nanotube fabrication and subsequently for wide technological applications. The silica nanotubes can be tuned to an emitter of visible light through the pyrolysis

Structural, optical and photocatalytic properties of flower-like ZnO nanostructures prepared by a facile wet chemical method

• Sini Kuriakose,
• Neha Bhardwaj,
• Jaspal Singh,
• Biswarup Satpati and
• Satyabrata Mohapatra

Beilstein J. Nanotechnol. 2013, 4, 763–770, doi:10.3762/bjnano.4.87

• spectra. Figure 6b shows the room temperature PL spectra of aged samples S2’ and S3’ showing an enhanced visible light emission and a suppressed near band edge (NBE) emission. The weak NBE emission from the ZnO nanocrystals strongly indicates the presence of a passivating Zn(OH)2 surface layer [16], as

Kelvin probe force microscopy of nanocrystalline TiO₂ photoelectrodes

• Alex Henning,
• Gino Günzburger,
• Res Jöhr,
• Yossi Rosenwaks,
• Biljana Bozic-Weber,
• Catherine E. Housecroft,
• Edwin C. Constable,
• Ernst Meyer and
• Thilo Glatzel

Beilstein J. Nanotechnol. 2013, 4, 418–428, doi:10.3762/bjnano.4.49

• built-in potential on the DSC performance at the TiO2/SnO2:F interface, investigated on a nanometer scale by KPFM measurements under visible light illumination, has not been resolved so far. Keywords: atomic force microscopy (AFM); dye-sensitized solar cells (DSC); Kelvin probe force microscopy (KPFM

• -based electrolyte and a platinum counter electrode as depicted in Figure 1. Upon visible-light excitation, dye molecules inject electrons into the conduction band, Ecb, of the semiconductor; the oxidized dye is subsequently reduced by the redox couple of the surrounding electrolyte. The generated

• the incident light since the nanoporous TiO2, deposited on top of the FTO-layer, is only about 10 μm thin and transparent to visible light (Eg = 3.2 eV). Due to the high n-dopant density of SnO2:F (ND ~ 1020), it can be approximated to being nearly metallic. Generally, the SnO2:F contact is regarded

Photocatalytic antibacterial performance of TiO₂ and Ag-doped TiO₂ against S. aureus. P. aeruginosa and E. coli

• Kiran Gupta,
• R. P. Singh,
• Ashutosh Pandey and
• Anjana Pandey

Beilstein J. Nanotechnol. 2013, 4, 345–351, doi:10.3762/bjnano.4.40

• bacterial strains under visible-light irradiation. The TiO2 and Ag-doped TiO2 photocatalysts were synthesized by acid catalyzed sol–gel technique and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV–vis spectroscopy and photoluminescence (PL). The XRD pattern revealed

• hand, TiO2 is also an excellent supporting metal oxide for the doping of silver nanoparticles due to its small crystal size and high surface area. The aim of this work is to investigate the comparative photocatalytic activity of TiO2 and Ag-doped TiO2 (visible light active) nanoparticles synthesized by

• investigated against Gram-positive Staphylococcus aureus (S. aureus), and Gram-negative Pseudomonas aeruginosa (P. aeruginosa) and Escherichia coli (E. coli) bacteria under visible light. Results and Discussion XRD of TiO2 and Ag-doped TiO2 The samples were annealed at 450 °C to achieve crystallization in TiO2

Near-field effects and energy transfer in hybrid metal-oxide nanostructures

• Ulrich Herr,
• Balati Kuerbanjiang,
• Cahit Benel,
• Giorgos Papageorgiou,
• Manuel Goncalves,
• Johannes Boneberg,
• Paul Leiderer,
• Paul Ziemann,
• Peter Marek and
• Horst Hahn

Beilstein J. Nanotechnol. 2013, 4, 306–317, doi:10.3762/bjnano.4.34

• semiconductors. Typically, noble metals are used for the metal nanostructures, since they offer both long term stability and strong resonant enhancements in the range of visible light. A general review of materials aspects in nanotechnology-based approaches in energy technology can be found in [8]. From the

Photoelectrochemical and Raman characterization of In₂O₃ mesoporous films sensitized by CdS nanoparticles

• Mikalai V. Malashchonak,
• Sergey K. Poznyak,
• Eugene A. Streltsov,
• Anatoly I. Kulak,
• Olga V. Korolik and
• Alexander V. Mazanik

Beilstein J. Nanotechnol. 2013, 4, 255–261, doi:10.3762/bjnano.4.27

• approximately 700 mV when increasing the temperature of the oxide annealing (Figure 7). Figure 8 shows the photocurrent–potential curves recorded under visible-light illumination of In2O3(200)/CdS and In2O3(400)/CdS heterostructures (curves 3 and 4) in an S2−-containing electrolyte. For comparison, similar

• illumination of the mesoporous In2O3 electrodes annealed at 200 °C (1) and 400 °C (2). Electrolyte: 0.1 M KOH solution. Photocurrent versus electrode potential curves recorded under visible-light illumination of the In2O3 (1, 2) and In2O3/CdS electrodes (3–5). The In2O3 films were annealed at 200 (1, 3) and

Nanostructure-directed chemical sensing: The IHSAB principle and the dynamics of acid/base-interface interaction

• James L. Gole and
• William Laminack

Beilstein J. Nanotechnol. 2013, 4, 20–31, doi:10.3762/bjnano.4.3

• transformation from acidic to basic sites. These studies also define a broadened interaction matrix as it extends from physisorption (sensing) applications to chemisorption and microreactor design. Recently, we have produced visible-light-absorbing TiO2−xNx photocatalyst nanoparticles in seconds at room

• . In situ nitridation of the TiO2 to form the oxinitride, TiO2−xNx [9][10][11], enhances the visible-light response, basicity and sensitivity of the decorated PS interface. At low fractional TiO2 depositions, NO2 dominates TiO2−xNx [11] and white-light excitation increases the sensor response in the

• the molecular structure and interaction, consistent with the IHSAB principle. This means that the sensitivity of the weaker metal oxides is enhanced by nitridation. Further, this process can be applied to create several potential visible-light-absorbing photocatalysts similar to TiO2−xNx [9][10]. We