Enhanced Fenton-like process over Z-scheme MoO3 surface decorated with Fe2O3 under visible light

Photocatalysts consisting of Z-scheme heterojunctions are commonly used in wastewater treatment due to their exceptional reactivity in photocatalysis and highly efficient visible-light utilization. In this work, Fe2O3-decorated MoO3 rods were synthesized through a two-step method and their photodegradation of methylene blue (MB) was evaluated. The Fe2O3/MoO3 rods were characterized by XRD, SEM, micro-Raman, XPS, UV-Vis DRS, and PL to investigate their structural, morphological, and optical properties. The results indicate that the photodegradation efficiency of Fe2O3/MoO3 improved through a reduction in the gap energy and persistence of a 1D hexagonal prism structure. The degradation rate of MB was enhanced from 31.7 to 91.5% after irradiation for 180 min owing to electron-hole separation and Fenton-like process. Formation of the OH radical is a key factor in the photodegradation reaction and with the addition of H2O2 the efficiency can further improve via a Fenton-like mechanism. Furthermore, the Z-scheme mechanism concurrently delineated. The Fe2O3/MoO3 rod composites were also found to retain high photocatalytic efficiency after being reused five times, which may be useful for future applications.

Optical nanoimaging of highly-confined phonon polaritons in atomically-thin nanoribbons of α-MoO3

Phonon polaritons (PhPs), collective modes hybridizing photons with lattice vibrations in polar insulators, enable nanoscale control of light. In recent years, the exploration of in-plane anisotropic PhPs has yielded new levels of confinement and directional manipulation of nano-light. However, the investigation of in-plane anisotropic PhPs at the atomic layer limit is still elusive. Here, we report the optical nanoimaging of highly-confined phonon polaritons in atomically-thin nanoribbons of α-MoO3 (5 atomic layers). We show that narrow α-MoO3 nanoribbons as thin as a few atomic layers can support anisotropic PhPs modes with a high confinement ratio (∼133 times smaller wavelength than that of light). The anisotropic PhPs interference fringe patterns in atomic layers are tunable depending on the PhP wavelength via changing the illumination frequency. Moreover, spatial control over the PhPs interference patterns is also achieved by varying the nanostructures' shape or nanoribbon width of atomically-thin α-MoO3. Our work may serve as an empirical reference point for other anisotropic PhPs that approach the thickness limit and pave the way for applications such as atomically integrated nano-photonics and sensing.

Guided Polaritons along the Forbidden Direction in MoO3 with Geometrical Confinement

Highly anisotropic materials show great promise for spatial control and the manipulation of polaritons. In-plane hyperbolic phonon polaritons (HPhPs) supported by α-phase molybdenum trioxide (MoO₃) allow for wave propagation with a high directionality due to the hyperbola-shaped isofrequency contour (IFC). However, the IFC prohibits propagations along the [001] axis, hindering information or energy flow. Here, we illustrate a novel approach to manipulating the HPhP propagation direction. We experimentally demonstrate that geometrical confinement in the [100] axis can guide HPhPs along the forbidden direction with phase velocity becoming negative. We further developed an analytical model to provide insights into this transition. Moreover, as the guided HPhPs are formed in-plane, modal profiles were directly imaged to further expand our understanding of the formation of HPhPs. Our work reveals a possibility for manipulating HPhPs and paves the way for promising applications in metamaterials, nanophotonics, and quantum optics based on natural van der Waals materials.

Heterogeneous catalysis with an organic–inorganic hybrid based on MoO3 chains decorated with 2,2′-biimidazole ligands

Polymeric [MoO₃(2,2′-biimidazole)]·H₂O outperforms other one-dimensional MoO₃-ligand hybrid materials as a heterogeneous and recyclable catalyst for (bio)olefin epoxidation and sulfoxidation.

Broad-Spectral-Range Sustainability and Controllable Excitation of Hyperbolic Phonon Polaritons in α-MoO3

Hyperbolic phonon polaritons (HPhPs) in orthorhombic-phase molybdenum trioxide (α-MoO₃ ) show in-plane hyperbolicity, great wavelength compression, and ultralong lifetime, therefore holding great potential in nanophotonic applications. However, its polaritonic response in the far-infrared (FIR) range remains unexplored due to challenges in experimental characterization. Here, monochromated electron energy loss spectroscopy (EELS) in a scanning transmission electron microscope (STEM) is used to probe HPhPs in α-MoO₃ in both mid-infrared (MIR) and FIR frequencies and correlate their behaviors with microstructures and orientations. It is found that low structural symmetry leads to various phonon modes and multiple Reststrahlen bands (RBs) over a broad spectral range (over 70 meV) and in different directions (55-63 meV and 119-125 meV along the b-axis, 68-106 meV along the c-axis, and 101-121 meV along the a-axis). These HPhPs can be selectively excited by controlling the direction of swift electrons. These findings provide new opportunities in nanophotonic and optoelectronic applications, such as directed light propagation, hyperlenses, and heat transfer.

Inkjet-printed paper-based semiconducting substrates for surface-enhanced Raman spectroscopy

As a powerful analytical tool of molecular detection, surface-enhanced Raman spectroscopy (SERS) has attracted great attention in varied fields. However, it has seriously impeded the development of SERS that the preparation process is generally complicated and traditional substrates lack eco-friendliness, economy and flexibility. Herein, we fabricated the inkjet-printed paper-based semiconducting SERS substrates for the first time via an inexpensive office inkjet printer with representative two-dimensional MoO_3-x nanosheets ink. Compared with conventional substrates, these paper-based semiconducting substrates not only could meet the requirements of simple and large-scale preparation, but also realize efficient sample collection by merely swabbing the surface. We obtained the detection limit concentration of rhodamine 6G as low as 10^-7 M. Furthermore, these flexible paper-based substrates were successfully applied to detect crystal violet and malachite green on the fish surface by swabbing. With immense potentiality in practical applications, the inkjet-printed paper-based semiconducting SERS substrates are expected to open a new prospect for SERS.

Growth of Molybdenum Trioxide Nanoribbons on Oriented Ag and Au Nanostructures: A Scanning Electron Microscopy (SEM) Study

We report the growth of molybdenum trioxide (MoO3) nanoribbons (NRs) on epitaxial Ag and oriented Au nanostructures (NSs) using an ultra-high vacuum (UHV)-molecular beam epitaxy (MBE) technique at different substrate temperatures. An approximately 2 nm silver (Ag) film has been deposited at different growth temperatures (using UHV-MBE) on cleaned Si(100), Si(110), and Si(111) substrates. For faceted Au NSs, an approximately 50 nm Au film has been deposited (using high-vacuum thermal evaporation) on a Si(100) substrate with a native oxide layer at the interface and the sample was annealed in low vacuum (≈10-2) and at high temperature (≈975°C). Scanning electron microscopy measurements were performed to determine the morphology of MoO3/Ag and MoO3/Au composite films. From energy dispersive X-ray spectroscopy elemental mapping and line scans it is found that faceted Au NSs are more favorable for the growth of MoO3 NRs than epitaxial Ag microstructures.

The Novel Z-Scheme Ternary-Component Ag/AgI/α-MoO3 Catalyst with Excellent Visible-Light Photocatalytic Oxidative Desulfurization Performance for Model Fuel

The novel ternary-component Ag/AgI/α-MoO₃ (AAM) photocatalyst was successfully fabricated by a facile hydrothermal method combined with a charge-induced physical adsorption and photo-reduced deposition technique. X-ray diffraction, scanning/transmission electron microscope, X-ray photoelectron, UV-vis diffuse reflectance, photoluminescence and electrochemical impedance spectroscopy were employed to characterize the composition, morphology, light-harvesting properties and charge transfer character of the as-synthesized catalysts. The ternary-component AAM heterojunctions exhibited an excellent visible-light photocatalytic oxidative desulfurization activity, in which the AAM-35 (35 represents weight percent of AgI in AAM sample) possessed the highest photocatalytic activity of the conversion of 97.5% in 2 h. On the basis of band structure analysis, radical trapping experiments and electron spin resonance (ESR) spectra results, two different catalytic mechanisms were suggested to elucidate how the photogenerated electron-hole pairs can be effectively separated for the enhancement of photocatalytic performance for dual composites AM-35 and ternary composites AAM-35 during the photocatalytic oxidative desulfurization (PODS) of thiophene. This investigation demonstrates that Z-scheme Ag/AgI/α-MoO₃ will be a promising candidate material for refractory sulfur aromatic pollutant’s removal in fossil fuel.

Methylene Blue-Fortified Molybdenum Trioxide Nanoparticles: Harnessing Radical Scavenging Property

A hybrid nanosystem with impeccable cellular imaging and antioxidant functionality is demonstrated. The microwave irradiation-derived molybdenum trioxide nanoparticles (MoO₃ NPs) were surface-functionalized with the cationic dye molecule, methylene blue (MB), which enables superior UV-visible absorbance and fluorescence emission wavelengths potential for bioimaging. The radical scavenging property of the pristine MoO₃ NPs and MoO₃-MB NPs were studied in vivo using Caenorhabditis elegans as the model system. Heat shock-induced oxidative stress in C. elegans was significantly resolved by the MoO₃-MB NPs, in agreement with the in vitro radical scavenging study by electron paramagnetic resonance spectroscopy. Hybrid nanostructures of MoO₃-MB demonstrate synergistic benefits in intracellular imaging with intrinsic biocompatibility and antioxidant behavior, which can facilitate application as advanced healthcare materials toward bioimaging and clinical therapeutics.

A morphological, enzymatic and metabolic approach to elucidate apoptotic-like cell death in fungi exposed to h- and α-molybdenum trioxide nanoparticles

The present study compares for the first time the effects of h-MoO3 and α-MoO3 against two fungal strains: Aspergillus niger and Aspergillus flavus. The h-MoO3 nanoparticles were more toxic to both fungi than α-MoO3. The toxic effects of h-MoO3 were more pronounced toward A. flavus, which presented a growth inhibition of 67.4% at 200 mg L-1. The presence of the nanoparticles affected drastically the hyphae morphology by triggering nuclear condensation and compromising the hyphae membrane. Further analysis of the volatile organic compounds (VOCs) produced by both fungi in the presence of the nanomaterials indicated important metabolic changes related to programmed cell death. These nanomaterials induced the production of specific antifungal VOCs, such as β-Elemene and t-Cadinol, by the fungi. The production of essential enzymes involved in fungal metabolism, such as acid phosphatase, naphthol-As-BI-phosphohydrolase, β-galactosidase, β-glucosidase and N-acetyl-β-glucosaminidase, reduced significantly in the presence of the nanomaterials. The changes in enzymatic production and VOCs corroborate the fact that these nanoparticles, especially h-MoO3, exert changes in the fungal metabolism, triggering apoptotic-like cell death responses in these fungi.

Tweaking the Electronic and Optical Properties of α-MoO3 by Sulphur and Selenium Doping - a Density Functional Theory Study

First-principles calculations were carried out to understand how anionic isovalent-atom doping affects the electronic structures and optical properties of α-MoO₃. The effects of the sulphur and selenium doping at the three unique oxygen sites (O_t, O_a, and O_t) of α-MoO₃ were examined. We found that the valence p orbitals of Sulphur/Selenium dopant atoms give rise to impurity bands above the valence band maximum in the band structure of α-MoO₃. The number of impurity bands in the doped material depends on the specific doping sites and the local chemical environment of the dopants in MoO₃. The impurity bands give rise to the enhanced optical absorptions of the S- and Se-doped MoO₃ in the visible and infrared regions. At low local doping concentration, the effects of the dopant sites on the electronic structure of the material are additive, so increasing the doping concentration will enhance the optical absorption properties of the material in the visible and infrared regions. Further increasing the doping concentration will result in a larger gap between the maximum edge of impurity bands and the conduction band minimum, and will undermine the optical absorption in the visible and infrared region. Such effects are caused by the local geometry change at the high local doping concentration with the dopants displaced from the original O sites, so the resulting impurity bands are no long the superpositions of the impurity bands of each individual on-site dopant atom. Switching from S-doping to Se-doping decreases the gap between the maximum edge of the impurity bands and conduction band minimum, and leads to the optical absorption edge red-shifting further into the visible and infrared regions.

Facile Water-Based Strategy for Synthesizing MoO3-x Nanosheets: Efficient Visible Light Photocatalysts for Dye Degradation

Nanostructured molybdenum oxides are promising materials for energy storage, catalysis, and electronic-based applications. Herein, we report the synthesis of MoO_3-x nanosheets (x stands for oxygen vacancy) via an environmentally friendly liquid exfoliation approach. The process involves the reflux of the bulk α-MoO₃ precursor in water at 80 °C for 7 days. Electron microscopy and atomic force microscopy show that the MoO_3-x nanosheets are a few nanometer thick. MoO_3-x nanosheets exhibit near infrared plasmonic property that can be enhanced by visible light irradiation for a short time (10 min). Photocatalytic activity of MoO_3-x nanosheets for organic dye decolorization is examined using two different dyes (rhodamine B and methylene blue). Under visible light irradiation, MoO_3-x nanosheets make a rapid decolorization for the dye molecules in less than 10 min. The simple synthesis procedure of MoO_3-x nanosheets combined with their remarkable photochemical properties reflect the high potential for using the nanosheets in a variety of applications.

Template conversion of MoO3 to MoS2 nanoribbons: synthesis and electrochemical properties

Electrochromic α-MoO₃ nanoribbons were prepared by a hydrothermal method and converted to MoS₂ with the same morphology.

Harvesting visible light with MoO3 nanorods modified by Fe(iii) nanoclusters for effective photocatalytic degradation of organic pollutants

Fe(iii) grafted MoO₃ nanorods were prepared by a hydrothermal-cum-impregnation technique.

Ag nanoparticle decorated molybdenum oxide structures: growth, characterization, DFT studies and their application to enhanced field emission

We report a simple single step growth of α-MoO₃ structures and energetically suitable site specific Ag nanoparticle (NP) decorated α-MoO₃ structures on varied substrates, having almost similar morphologies and oxygen vacancies. We elucidate possible growth mechanisms in light of experimental findings and density functional theory (DFT) calculations. We experimentally establish and verified by DFT calculations that the MoO₃(010) surface is a weakly interacting and stable surface compared to other orientations. From DFT study, the binding energy is found to be higher for (100) and (001) surfaces (∼-0.98 eV), compared to the (010) surface (∼-0.15 eV) and thus it is likely that Ag NP formation is not favorable on the MoO₃(010) surface. The Ag decorated MoO₃ (Ag-MoO₃) nanostructured sample shows enhanced field emission properties with an approimately 2.1 times lower turn-on voltage of 1.67 V μm^-1 and one order higher field enhancement factor (β) of 8.6 × 10⁴ compared to the MoO₃ sample without Ag incorporation. From Kelvin probe force microscopy measurements, the average local work function (Φ) is found to be approximately 0.47 eV smaller for the Ag-MoO₃ sample (∼5.70 ± 0.05 eV) compared to the MoO₃ sample (∼6.17 ± 0.05 eV) and the reduction in Φ can be attributed to the shifting Fermi level of MoO₃ toward vacuum via electron injection from Ag NPs to MoO₃. The presence of oxygen vacancies together with Ag NPs lead to the highest β and lowest turn-on field among the reported values under the MoO₃ emitter category.

Novel Fabrication and Enhanced Photocatalytic MB Degradation of Hierarchical Porous Monoliths of MoO3 Nanoplates

Porous monoliths of MoO₃ nanoplates were synthesized from ammonium molybdate (AHM) by freeze-casting and subsequent thermal treatment from 300 to 600 °C. Pure orthorhombic MoO₃ phase was obtained at thermal treatment temperature of 400 °C and above. MoO₃ monoliths thermally treated at 400 °C displayed bimodal pore structure, including large pore channels replicating the ice crystals and small pores from MoO₃ sheets stacking. Transmission electron microscopy (TEM) images revealed that the average thicknesses of MoO₃ sheet were 50 and 300 nm in porous monoliths thermally treated at 400 °C. The photocatalytic performance of MoO₃ was evaluated through degradation of methylene blue (MB) under visible light radiation and MoO₃ synthesized at 400 °C exhibited strong adsorption performance and best photocatalytic activity for photodegradation of MB of 99.7% under visible illumination for 60 min. MoO₃ photocatalyst displayed promising cyclic performance, and the decolorization efficiency of MB solution was 98.1% after four cycles.

A high-performance nanobridged MoO3 UV photodetector based on nanojunctions with switching characteristics

Ultraviolet photodetectors (UVPDs) were fabricated via the in situ growth of orthorhombic MoO₃ nanobelts among interdigital electrodes. Two types of nanojunction, touching and interpenetration, were formed between neighboring nanobelts at different growth conditions. The photoresponse mechanism of the UVPDs greatly depends on the type of nanojunction. Nanojunctions formed with touching nanobelts possess switching characteristics due to the barrier height variation along with the UV illumination. The UVPD with the touching structure exhibits low noise, high UV sensitivity and fast speed, having a dark current of 1.4 nA, an on/off ratio of over 100 and a response time of below 1 s, at an applied voltage of 10 V. The enhanced performance can be attributed to the switching characteristics of the touching nanojunction.

Recent advances in the synthesis and application of photocatalytic metal–metal oxide core–shell nanoparticles for environmental remediation and their recycling process

Metal–metal oxide core–shell nanoparticles have received enormous research attention owing to their fascinating physicochemical properties and extensive applications. In this review we have discussed the challenges and recent advances in their synthesis and application.

Na0.5Ce0.5MoO4 as a new light absorption material to efficiently degrade RhB under visible light irradiation

Na_0.5Ce_0.5MoO₄, with a high visible light absorption and a high conductivity, remarkably improves photocatalytic activity of Na_0.5Ce_0.5MoO₄/MoO₃ heterojunctions under visible light irradiation.

Film Growth Rates and Activation Energies for Core-Shell Nanoparticles Derived from a CVD Based Aerosol Process

Silica core-shell nanoparticles of about 60–120 nm with a closed outer layer of bismuth or molybdenum oxide of 1–10 nm were synthesized by an integrated chemical vapor synthesis/chemical vapor deposition process at atmospheric pressure. Film growth rates and activation energies were derived from transmission electron microscopy (TEM) images for a deposition process based on molybdenum hexacarbonyl and triphenyl bismuth as respective coating precursors. Respective activation energies of 123 ± 10 and 155 ± 10 kJ/mol are in good agreement with the literature and support a deposition mechanism based on surface-induced removal of the precursor ligands. Clean substrate surfaces are thus prerequisite for conformal coatings. Integrated aerosol processes are solvent-free and intrinsically clean. In contrast, commercial silica substrate particles were found to suffer from organic residues which hinder shell formation, and require an additional calcination step to clean the surface prior to coating. Dual layer core-shell structures with molybdenum oxide on bismuth oxide were synthesized with two coating reactors in series and showed similar film growth rates.

Alteration of architecture of MoO₃ nanostructures on arbitrary substrates: growth kinetics, spectroscopic and gas sensing properties

MoO3 nanostructures have been grown in thin film form on five different substrates by RF magnetron sputtering and subsequent annealing; non-aligned nanorods, aligned nanorods, bundled nanowires, vertical nanorods and nanoslabs are formed respectively on the glass, quartz, wafer, alumina and sapphire substrates. The nanostructures formed on these substrates are characterized by AFM, SEM, GIXRD, XPS, micro-Raman, diffuse reflectance and photoluminescence spectroscopy. A detailed growth model for morphology alteration with respect to substrates has been discussed by considering various aspects such as surface roughness, lattice parameters and the thermal expansion coefficient, of both substrates and MoO3. The present study developed a strategy for the choice of substrates to materialize different types MoO3 nanostructures for future thin film applications. The gas sensing tests point towards using these MoO3 nanostructures as principal detection elements in gas sensors.

Direct conversion of multilayer molybdenum trioxide to nanorods as multifunctional electrodes in lithium-ion batteries

In this study we prepared molybdenum trioxide (MoO3) nanorods having average lengths of 0.5-1.5 μm and widths of approximately 100-200 nm through a one-step mechanical break-down process involving favorable fracturing along the crystal direction. We controlled the dimensions of the as-prepared nanorods by applying various imposing times (15-90 min). The nanorods prepared over a reaction time of 90 min were, on average, much shorter and narrower relative to those obtained over 30 min. Evaluations of lithium-ion storage properties revealed that the electrochemical performance of these nanorods was much better than that of bulk materials. As cathodes, the nanorods could deliver a high specific capacity (>315 mA h g(-1)) with losses of less than 2% in the first cycle at a rate of 30 mA g(-1); as anodes, the specific capacity was 800 mA h g(-1) at a rate of 50 mA g(-1). Relative to α-MoO3 microparticles, these nanorods displayed significantly enhanced lithium-ion storage properties with higher reversible capacities and better rate performance, presumably because their much shorter diffusion lengths and higher specific surface areas allowed more-efficient insertion/deinsertion of lithium ions during the charge/discharge process. Accordingly, enhanced physical and/or chemical properties can be obtained through appropriate nanostructuring of materials.

Toxicity of nano molybdenum trioxide toward invasive breast cancer cells

Current chemotherapy is limited by the nature of invasive cancer cells, which are similar to cancer stem cells. Nanomaterials provide a potential alternate mode of cancer therapy. This study investigated the cytotoxicity of molybdenum trioxide (MoO3) nanoplates toward invasive breast cancer iMCF-7 cells by analyzing morphological changes and performing Western blot and flow cytometry analyses. The findings suggested that MoO3 exposure induces apoptosis and generates reactive oxygen species (ROS) in iMCF-7 cells. This study revealed the potential utility of MoO3 for treating metastatic cancer cells, which might enable advancements in cancer therapy.

The Synthesis of α-MoO₃ by Ethylene Glycol

This study investigated the use of ethylene glycol to form α-MoO₃ (molybdenum trioxide) from ammonium molybdate tetrahydrate at various sintering temperatures for 1 h. During the sintering process, the morphologies of the constituents were observed using scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy was used to explain the reaction process. In this work, the results obtained using X-ray photoelectron spectroscopy (XRD) demonstrated that, when the molybdenum trioxide powder was treated thermally at 300 °C, the material exhibited crystallinity. The peaks were indexed to correspond with the (110), (040), (021), (111), and (060) crystallographic planes, and the lattice parameters of a, b, and c were about 3.961, 13.876, and 3.969 Å. Using these observations, we confirmed that orthorhombic α-MoO₃ was formed for sintering temperatures from 300 to 700 °C. Pattern images were obtained by the selected area electron diffraction pattern (SAED) technique, and the d distance of the high resolution transmission electron microscopy (HRTEM) images were almost 0.39 and 0.36 nm, and the Mo 3d_5/2, Mo 3d_3/2, and O 1s of X-ray photoelectron spectroscopy (XPS) were located at 233.76, 237.03, and 532.19 eV, which also demonstrated that α-MoO₃ powder had been synthesized.

Tuning electronic and magnetic properties of MoO3 sheets by cutting, hydrogenation, and external strain: a computational investigation

Density functional theory computations were performed to examine the electronic and magnetic properties of MoO3 two-dimensional (2D) nanosheets and their derived one-dimensional (1D) nanoribbons (NRs). The pristine 2D MoO3 sheet is a nonmagnetic semiconductor with an indirect band gap, but can be transformed to a magnetic metal when the surface O atoms are saturated by H. Depending on the cutting pattern, the pristine 1D NRs can be indirect band gap nonmagnetic semiconductors, magnetic semiconductors or magnetic metals. The fully hydrogenated NRs are metallic, while the edge-passivated NRs possess the nonmagnetic semiconducting feature, but with narrower band gap values compared to the pristine NRs. Both the 2D monolayer MoO3 sheet and the 1D nanoribbons maintain the semiconducting behaviors when exerting axial strain. These findings provide a simple and effective route to tune the magnetic and electronic properties of MoO3 nanostructures in a wide range and also facilitate the design of MoO3-based nanodevices.

Structure and compositional control of MoO3 hybrids assembled by nanoribbons for improved pseudocapacitor rate and cycle performance

Hierarchical structures of transition metal oxides with well-defined compositions are crucial for achieving advanced electrodes for energy storage devices. Herein, we first demonstrate the hierarchically structured MoO(3) assembled by twisted nanoribbons with a hybrid composition for improved rate capability and cycle stability of the pseudocapacitor. The hierarchical, flower-like structures of MoO(3) assembled by hybrid nanoribbons were induced by the specific interactions of MoO(3) interlayers with ionic liquids (ILs), as proven by spectroscopic and electrochemical analyses. Furthermore, the interlayer modification of MoO(3) crystallites through IL interaction enabled unique pseudocapacitive behaviors for fast and reversible proton intercalation/extraction that could not be observed by conventional MoO(3). In this research, we used control samples to prove our hypothesis that the capacitor performances of MoO(3) can be improved by a hierarchical structure and hybrid composition. These structural and compositional features of the hybrids greatly enhanced the rate capability by fast ion diffusion while improving cycle stability due to efficient stress release. More importantly, we observed the dramatic enhancement of ion diffusion coefficients of hybrids for good rate capability, because ion diffusion into the layered structure is very critical for maintaining specific capacitance at the high current density. The facilitated ion diffusion is attributed to the hierarchical nanostructure for a short diffusion length and ion accessibility, the high ion mobility in hybrids, and the interlayer modification of MoO(3) by IL coating. Therefore, this research offers new insight into the rational design of advanced electrode materials on the basis of the hierarchical complex structures of transition metal oxides with well-defined hybrid compositions for future applications in energy conversion and storage.

One-dimensional inorganic nanostructures: synthesis, field-emission and photodetection

One-dimensional inorganic nanostructures have drawn prime attention due to their potential for understanding fundamental physical concepts and constructing nanoscale electronic and optoelectronic devices. This critical review mainly focuses on our recent research progresses in 1D inorganic nanostructures, including their rational synthesis and potential applications, with an emphasis on field-emitter and photodetector applications. Firstly, we will discuss the rational design of synthetic strategies and the synthesis of 1D nanostructures via a vapour phase approach. Secondly, we will present our recent progresses with respect to several kinds of important inorganic nanostructures and their field-emission and photoconductivity characteristics. Finally, we conclude this review with some perspectives/outlook and future research in these fields (212 references).