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

• Bi2MoO6, which originates from the increased charge separation at the interface [22][23][24][25][26][27][28][29][30]. Recently, Ag-based compounds (e.g., Ag3PO4, Ag3VO4, Ag2CrO4, and Ag2CO3) [34][35][36] have emerged as good VLD photocatalysts for pollutant removal. Ag2CO3 exhibits a high visible-light

• /Ag2CO3/Bi2MoO6 [32] and Ag2MoO4/Bi2MoO6 [22]. This result shows that the charge separation efficiency is enhanced in ACO/BMO-30. Photocatalytic performance The efficiency of Ag2CO3/Bi2MoO6 heterostructures in the photocatalytic degradation of industrial dyes (RhB, MO and MB), and the antibiotic TC of the

Lead-free hybrid perovskites for photovoltaics

• Oleksandr Stroyuk

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

• are withdrawn to the Spiro-MeOTAD HTL and then – into the gold back contact (Figure 11b). The charge separation efficiency is evidenced by a relatively high FF of almost 80%, while a high Voc of 0.83 V observed for such cells attests to the structural perfection of the light-absorbing HP layer [84]. A

Spin-coated planar Sb₂S₃ hybrid solar cells approaching 5% efficiency

• Pascal Kaienburg,
• Benjamin Klingebiel and
• Thomas Kirchartz

Beilstein J. Nanotechnol. 2018, 9, 2114–2124, doi:10.3762/bjnano.9.200

• needed. Two basic factors that impact the solar cell performance of a given material are the device architecture, which defines the mechanism of charge separation, and the deposition method for the absorber, which affects the film and electronic material quality. Sb2S3 is commonly applied in an extremely

Localized photodeposition of catalysts using nanophotonic resonances in silicon photocathodes

• Evgenia Kontoleta,
• Sven H. C. Askes,
• Lai-Hung Lai and
• Erik C. Garnett

Beilstein J. Nanotechnol. 2018, 9, 2097–2105, doi:10.3762/bjnano.9.198

• ][31]. An exception is the work of Li et al. [27], where charge separation was achieved at different crystal facets of BiVO4 nanocrystals for selective photodeposition of metal and metal oxide catalytic nanoparticles. Nevertheless, this method for the moment is limited to this specific material and

• carriers (Figure 2). An 18 nm amorphous TiO2 layer was conformally deposited on the silicon nanostructures by using atomic layer deposition (ALD). This layer assists with charge separation, stabilizes the silicon surface and helps to passivate trap states, leading to well-known improvements in photo

• platinum nanoparticles does not allow for a “back” transfer of electrons. Hence, charge separation is promoted, which allows further reduction of hexachloroplatinate to Pt(0) on one of the existing platinum nanoparticles rather than in new locations. As a result, the initial platinum nanoparticle formation

Controllable one-pot synthesis of uniform colloidal TiO₂ particles in a mixed solvent solution for photocatalysis

• Jong Tae Moon,
• Seung Ki Lee and
• Ji Bong Joo

Beilstein J. Nanotechnol. 2018, 9, 1715–1727, doi:10.3762/bjnano.9.163

• photocatalyst must be narrow in order to facilitate the facile adsorption of the low energy photon and high harvesting efficiency under visible-light irradiation conditions [11]. To enhance charge separation efficiency and extend the lifetime of photoexcited electron–hole pairs, properties such as a crystalline

• phase as well as a large surface area, should have beneficial effects including light absorption, charge separation and facile surface reaction, all resulting in the enhanced photocatalytic efficiency towards RhB degradation. As pointed out in the Introduction section and in our previous study, many

• absorption and charge separation [20]. It should be noted that the increased activity of P25 TiO2 is due to the electron sink of rutile preventing electron–hole recombination in the anatase phase. It allows an anatase-originating hole to move to the surface, resulting in a high surface reaction under UV

Sheet-on-belt branched TiO₂(B)/rGO powders with enhanced photocatalytic activity

• Huan Xing,
• Wei Wen and
• Jin-Ming Wu

Beilstein J. Nanotechnol. 2018, 9, 1550–1557, doi:10.3762/bjnano.9.146

• TiO2(B) is usually adopted to construct phase junctions with anatase TiO2 for applications in photocatalysis to facilitate charge separation; its intrinsic photocatalytic activity, especially when in the form of one- or three-dimensional nanostructures, has been rarely reported. In this study, a sheet

• assist the photodegradation of phenol in water under UV light illumination. The enhanced photocatalytic activity can be attributed to the significantly increased surface area and enhanced charge separation. Keywords: branched nanostructure; photocatalysis; reduced graphene oxide; TiO2(B); Introduction

• safety and rate capability [11][17][18][19][20]. For photocatalytic applications, TiO2(B) is usually combined with anatase TiO2 to construct a multiphase heterostructure to enhance charge separation and in turn the photocatalytic activity [21][22][23][24][25]. For example, Yang et al. synthesized anatase

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

• activity by achieving a more efficient charge separation, increasing the lifetime of the charge carriers, inhibiting the recombination of electron–hole pairs and facilitating interfacial charge transfer to adsorbed substrates [91][92]. In this review we have focused on modification of nanostructured TiO2

• for efficient photocatalytic Cr(VI) reduction [134]. They prepared the photocatalyst using a direct-wrapped route followed by hydrothermal etching. The high charge separation efficiency and redox ability are due to the synergetic effect of formation of a Z scheme photocatalytic process and its

• photocatalytic reduction of Cr(VI) Modification of TiO2 with semiconductor oxides having a suitable band gap is a novel approach for significant charge separation, long lifetime of the charge carriers and effective interfacial charge transfer, which are properties that lead to enhanced photocatalytic activity

Computational exploration of two-dimensional silicon diarsenide and germanium arsenide for photovoltaic applications

• Sri Kasi Matta,
• Chunmei Zhang,
• Yalong Jiao,
• Anthony O'Mullane and
• Aijun Du

Beilstein J. Nanotechnol. 2018, 9, 1247–1253, doi:10.3762/bjnano.9.116

• suitable for photovoltaic applications, such as excellent visible light absorption, favorable exciton formation, and charge separation are equally essential for two-dimensional (2D) materials. Here, we systematically study 2D group IV–V compounds such as SiAs2 and GeAs2 with regard to their structural

Facile synthesis of a ZnO–BiOI p–n nano-heterojunction with excellent visible-light photocatalytic activity

• Mengyuan Zhang,
• Jiaqian Qin,
• Pengfei Yu,
• Bing Zhang,
• Mingzhen Ma,
• Xinyu Zhang and
• Riping Liu

Beilstein J. Nanotechnol. 2018, 9, 789–800, doi:10.3762/bjnano.9.72

• favor. As can be clearly seen, B-1 and B-6 exhibited an extremely strong intensity, demonstrating the lower charge separation efficiency of pure BiOI and ZnO. The intensity greatly decreased as the BiOI/ZnO ratio equals 1:3, revealing that the formation of the ZnO/BiOI heterostructured composite is

• beneficial for improving the charge separation ability. The light adsorption ability and the band gap structure are some of the decisive factors for photocatalysis. Therefore, the UV–vis diffuse reflection spectra (UV-DRS) is worthy of study to explore their optical properties. The UV-DRS results are shown

Perovskite-structured CaTiO₃ coupled with g-C₃N₄ as a heterojunction photocatalyst for organic pollutant degradation

• Ashish Kumar,
• Christian Schuerings,
• Suneel Kumar,
• Ajay Kumar and
• Venkata Krishnan

Beilstein J. Nanotechnol. 2018, 9, 671–685, doi:10.3762/bjnano.9.62

• in the literature [32][33]. Xian and coworkers have studied the photocatalytic degradation of MO under simulated solar light irradiation in BaTiO3–g-C3N4 composites with an efficient charge separation of photogenerated charge carriers at the interfaces [30]. Leong et al. have successfully made a

• materials [37]. Thus, the fabrication of a binary heterojunction of CT with a narrow band gap semiconductor like g-C3N4 can enhance the photocatalytic activity by effective charge separation and transfer across the heterojunction. Moreover, a sheet-like morphology can promote the photocatalytic activity, as

• degradation. Thus, the recycling results reflect the commendable stability of the CTCN heterojunction and support its potential for environmental remediation applications. Mechanism of photocatalytic activity The attainment of high efficiency of charge separation during a photocatalytic reaction plays an

Mechanistic insights into plasmonic photocatalysts in utilizing visible light

• Kah Hon Leong,
• Azrina Abd Aziz,
• Lan Ching Sim,
• Pichiah Saravanan,
• Min Jang and
• Detlef Bahnemann

Beilstein J. Nanotechnol. 2018, 9, 628–648, doi:10.3762/bjnano.9.59

• spatial charge separation of photoinduced carriers by creating an alternate permutation of band edges at the interface [146]. Some researchers found that both titanium nitride (TiN) and zirconium nitride (ZrN) displayed similar optical properties as Au and can replace Au NPs for vis–NIR light absorption

Facile synthesis of ZnFe₂O₄ photocatalysts for decolourization of organic dyes under solar irradiation

• Arjun Behera,
• Debasmita Kandi,
• Sanjit Manohar Majhi,
• Satyabadi Martha and
• Kulamani Parida

Beilstein J. Nanotechnol. 2018, 9, 436–446, doi:10.3762/bjnano.9.42

• band-edge potential, a mechanism of the photocatalytic reaction has been proposed which is discussed later. Electrochemical impedance study Impedance measurements are commonly used to determine the charge transfer, resistance, and effective charge separation processes occurring at electrode–electrolyte

• transfer, effective charge separation and high conductivity (Figure 9). This result is well supported by PL measurements and photocatalytic activity. Photocatalytic activity Decolourization of Congo red under solar-light irradiation The photocatalytic activity in the decolourization of 10 ppm Congo red (CR

• constant, respectively. In the above equation, n determines the transition in a semiconductor, i.e., n = 1/2 for a direct transition and n = 2 for an indirect transition. Figure 4b shows that the band-gap energy of ZFO-500 C is 1.81 eV. PL analysis The PL emission can be used to investigate the charge

Sugarcane juice derived carbon dot–graphitic carbon nitride composites for bisphenol A degradation under sunlight irradiation

• Lan Ching Sim,
• Jing Lin Wong,
• Chen Hong Hak,
• Jun Yan Tai,
• Kah Hon Leong and
• Pichiah Saravanan

Beilstein J. Nanotechnol. 2018, 9, 353–363, doi:10.3762/bjnano.9.35

• of g-C3N4. Hence, the charge separation efficiency should not be one of the main factors responsible for the enhancement of the photocatalytic activity of CD/g-C3N4. Instead, the light absorption capability was the dominant factor since the photoreactivity correlated well with the ultraviolet–visible

• structure [31] and the hydrogenation of g-C3N4 [32] could be an alternative to increase the light-harvesting ability and charge separation efficiency. Our group has reported the self-modification of g-C3N4 structures using alkaline [28] and acid treatment [29] to overcome the limitations of g-C3N4. Despite

• irradiation because the UCPL properties of CDs (which could overcome the low energy of NIR-light photons to initiate the excitation of electrons) are not detected in Figure 3b. The PL spectra in Figure 3d were evaluated to determine the charge separation efficiency of all composites. The recombination of

CdSe nanorod/TiO₂ nanoparticle heterojunctions with enhanced solar- and visible-light photocatalytic activity

• Fakher Laatar,
• Hatem Moussa,
• Halima Alem,
• Lavinia Balan,
• Emilien Girot,
• Ghouti Medjahdi,
• Hatem Ezzaouia and
• Raphaël Schneider

Beilstein J. Nanotechnol. 2017, 8, 2741–2752, doi:10.3762/bjnano.8.273

• recombination of photogenerated charge carriers (electrons and holes). To address these problems, a number of studies have been devoted to the improvement of light absorption and charge separation by hybridizing TiO2 with narrow bandgap semiconductors, doping with metal or nonmetal elements, association with

• separation. The interfacial electron transfer between two semiconductors has gained significant interest because the heterojunction improves both the optical absorption in the visible range and the charge separation yield and thus the charge carrier lifetime [3][4][5][6][7][8]. The photocatalytic activity is

• structure, the CdSe/TiO2 composites exhibit full visible and near-infrared light absorption and improved photocatalytic activity via charge separation between CdSe and TiO2 materials. The CdSe (2 wt %)/TiO2 composite was demonstrated to be the more efficient for the degradation of rhodamine B both under

Enhanced photoelectrochemical water splitting performance using morphology-controlled BiVO₄ with W doping

• Xin Zhao and
• Zhong Chen

Beilstein J. Nanotechnol. 2017, 8, 2640–2647, doi:10.3762/bjnano.8.264

• BiVO4 by simply tuning the solvent ratio in precursor solutions. Planar and porous W-doped BiVO4 thin films were prepared and compared. The porous film, which exhibits increased surface area and enhanced light absorption, has displayed enhanced charge separation and interfacial charge injection. Our

• quantitative analysis showed an enhancement of about 50% of the photoelectrochemical performance for the porous structure compared to the planar structure. This enhancement is attributed to improved light absorption (13% increase), charge separation (14% increase), and interfacial charge injection (20

• % increase). Keywords: bismuth vanadate; charge separation; nanostructure; photoelectrochemical water splitting; Introduction Solar hydrogen generation is one of the most promising approaches to create clean energy and to overcome the environmental problems associated with use of conventional fossil fuels

Systematic control of α-Fe₂O₃ crystal growth direction for improved electrochemical performance of lithium-ion battery anodes

• Nan Shen,
• Miriam Keppeler,
• Barbara Stiaszny,
• Holger Hain,
• Filippo Maglia and
• Madhavi Srinivasan

Beilstein J. Nanotechnol. 2017, 8, 2032–2044, doi:10.3762/bjnano.8.204

• interfacial lithium accommodation along with charge separation at phase boundaries proposed by Jamnik and Maier [56]. After conversion of α-Fe2O3, resulting in Fe finely dispersed in a Li2O matrix, additional lithium is supposed to be accommodated on the Li2O surfaces, whereas the electrons are transferred to

Spin-dependent transport and functional design in organic ferromagnetic devices

• Guichao Hu,
• Shijie Xie,
• Chuankui Wang and
• Carsten Timm

Beilstein J. Nanotechnol. 2017, 8, 1919–1931, doi:10.3762/bjnano.8.192

• organic magnetic devices with one ferromagnetic and one nonmagnetic electrode. Wang et al. [27][28] have performed theoretical studies of electron transport in OFs and have proposed spin–charge separation and spin filtering. π-Conjugated OFs with spin radicals are ideal materials for device design since

Two-dimensional carbon-based nanocomposites for photocatalytic energy generation and environmental remediation applications

• Suneel Kumar,
• Ashish Kumar,
• Ashish Bahuguna,
• Vipul Sharma and
• Venkata Krishnan

Beilstein J. Nanotechnol. 2017, 8, 1571–1600, doi:10.3762/bjnano.8.159

• semiconductor material occurs in three main steps, (1) absorption of light, (2) charge separation, (3) redox reactions on the catalyst surface. The first step involves the absorption of light by the photocatalyst and generation of electron–hole pairs in the CB and VB. The second step involves the charge

• nanoparticles and accelerate the photocatalytic rate by introducing more reaction sites and promoting charge separation in semiconductors [115]. In water splitting reactions, generally noble metals (e.g., Pt, Rh) and some metal oxides (e.g., NiO) act as the cocatalyst and these are loaded on the surface of

• photocatalysts to produce more reactive sites and to reduce the activation energy for H2 and O2 gas evolution. Cocatalysts also enhances the charge separation in photocatalytic materials because of their high work function. This high work function of noble metals and some metal oxides accelerates the transfer of

Energy-level alignment at interfaces between manganese phthalocyanine and C₆₀

• Daniel Waas,
• Florian Rückerl,
• Martin Knupfer and
• Bernd Büchner

Beilstein J. Nanotechnol. 2017, 8, 927–932, doi:10.3762/bjnano.8.94

• (opto-)electronic devices [1][2][3][4][5][6][7][8][9][10]. A key issue in any device is the energetics at the device interfaces as it determines charge transport across or charge separation at the corresponding interface [11][12]. Thus, it is not surprising that the investigation of organic

• phthalocyanine-based (model) devices have been realized [28][29][30][31][32][33]. In particular, organic photovoltaic cells containing, e.g., copper phthalocyanine (CuPc) can be found rather frequently in the literature [28][30][34][35][36]. There, the charge separation at interfaces between the phthalocyanine

• charge separation at the interface is significantly reduced. Interestingly, the energy-level alignment at the interface between MnPc and C60, prepared on a gold substrate depends on the deposition sequence. The HOMO offset differs by about 0.3 eV. Furthermore, the position of the Fermi level in MnPc is

High photocatalytic activity of Fe₂O₃/TiO₂ nanocomposites prepared by photodeposition for degradation of 2,4-dichlorophenoxyacetic acid

• Shu Chin Lee,
• Hendrik O. Lintang and
• Leny Yuliati

Beilstein J. Nanotechnol. 2017, 8, 915–926, doi:10.3762/bjnano.8.93

• of the best modifiers, the use of a co-catalyst has been recognized to improve the photocatalytic performance of semiconductor photocatalysts as it promotes charge separation and suppresses photocorrosion of the semiconductor photocatalyst [3][4]. One of the potential co-catalyst modifiers is iron

Synthesis of graphene–transition metal oxide hybrid nanoparticles and their application in various fields

• Arpita Jana,
• Elke Scheer and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2017, 8, 688–714, doi:10.3762/bjnano.8.74

• significantly. The introduction of graphene into TiO2 results in increased conductivity of the hybrid material, higher transparency and efficient charge separation of the system which causes enhanced photocatalytic activity and other novel properties [81]. Also, due to its high conductivity, graphene is highly

Study of the surface properties of ZnO nanocolumns used for thin-film solar cells

• Neda Neykova,
• Jiri Stuchlik,
• Karel Hruska,
• Ales Poruba,
• Zdenek Remes and
• Ognen Pop-Georgievski

Beilstein J. Nanotechnol. 2017, 8, 446–451, doi:10.3762/bjnano.8.48

• developed solar cells based on a three dimensional (3-D) design, in which periodically ordered zinc oxide nanocolumns (ZnO NCs) are used as a front electrode, have been of great interest, because they would exceed in the ultimate light trapping and provide excellent charge separation [5][6][7]. Due to the

Photo-ignition process of multiwall carbon nanotubes and ferrocene by continuous wave Xe lamp illumination

• Paolo Visconti,
• Patrizio Primiceri,
• Daniele Longo,
• Luciano Strafella,
• Paolo Carlucci,
• Mauro Lomascolo,
• Arianna Cretì and
• Giuseppe Mele

Beilstein J. Nanotechnol. 2017, 8, 134–144, doi:10.3762/bjnano.8.14

• point of view, the suggested evolution of ignition process has been summarized in the Figure 17. As reported in Figure 17, the photo-induced process of charge separation, promoted by UV–vis–IR light irradiation (photon energy h∙ν = h∙c/λ with 380 nm < λ < 1000 nm, c speed of light and h Planck constant

Role of RGO support and irradiation source on the photocatalytic activity of CdS–ZnO semiconductor nanostructures

• Suneel Kumar,
• Rahul Sharma,
• Vipul Sharma,
• Gurunarayanan Harith,
• Vaidyanathan Sivakumar and
• Venkata Krishnan

Beilstein J. Nanotechnol. 2016, 7, 1684–1697, doi:10.3762/bjnano.7.161

• occurs in both. Hence, the generation of higher number of electron–hole pairs, their effective charge separation and charge transfer are the major factors responsible for the better activity of the photocatalysts under natural sunlight compared to the visible light irradiation using a solar simulator

• , which could be attributed to the enhanced photo-generated charge separation, facile charge transfer and strong adsorption of dye on to RGO. In addition, superior photocatalytic activity was observed for the nanocomposites irradiated under natural sunlight than visible light from solar simulator. This

Scanning probe microscopy studies on the adsorption of selected molecular dyes on titania

• Jakub S. Prauzner-Bechcicki,
• Lukasz Zajac,
• Piotr Olszowski,
• Res Jöhr,
• Antoine Hinaut,
• Thilo Glatzel,
• Bartosz Such,
• Ernst Meyer and
• Marek Szymonski

Beilstein J. Nanotechnol. 2016, 7, 1642–1653, doi:10.3762/bjnano.7.156

• charge separation and transport functions are separated. Now, the properties of the semiconductor–sensitizer junction may increase the conversion efficiency in the photovoltaic device. In view of this, it is essential to study the adsorption properties and the charge transfer of organic dyes on the