We have designed and synthesized CoS2 and MoS2/CoS2 nanotube arrays by one-step hydrothermal method using Co(OH)2 nanorod arrays as the template. The products were characterized by X-ray diffraction pattern, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, and transmission electron microscopy. The MoS2/CoS2 electrode is demonstrated to have a relatively high area capacitance of 142.5 mF cm–2 at 1 mA cm–2, which is higher than that of CoS2 or MoS2 electrode. Besides, the electrode also shows excellent cycle stability of 1000 cycles with 92.7% retention, which is also superior to that of CoS2 and MoS2 electrodes. These results indicate that MoS2/CoS2 nanotube arrays have potential as electrode materials of supercapacitors because of the synergistic reaction of MoS2 (which supplies the specific surface area and effective electrolyte accessibility) and CoS2 (which serves as a conductive channel and reduces the phenomenon of aggregation). The design of MoS2/CoS2 architecture may open up a new strategy for synthesizing promising electrode materials for supercapacitors.

Novel three dimensional MoO2–graphene (MoO2–G) flower-like nanostructures are synthesized via a facile hydrothermal reaction. It has been shown that the MoO2–G demonstrates enhanced supercapacitive performance compared to pure MoO2 particles. The excellent electrochemical performance is attributed to the introduction of graphene and a hierarchical nanostructure, providing a large surface area and low equivalent series resistance.

Herein, we demonstrate the synthesis of a Bi2MoO6 nanorod array followed by the deposition of a BiVO4 absorber layer. This heterojunction yielded a photocurrent density of 250 μA cm−2 at 0.8 VSCE, which is 21 times that produced by a planar Bi2MoO6 array under the same conditions. Moreover, in situ X-ray photoelectron spectroscopy clearly confirmed the improvement of the electron transport and charge separation afforded by the heterostructure, features that efficiently enhanced the photoelectrochemical properties of the array.

A facile hydrothermal reaction has been developed for the large-scale growth of Bi2MoO6 nanosheets on conductive substrates with robust adhesion as high performance electrodes for electrochemical capacitors. It was found that the nickel foam facilitates the formation of a uniform nanosheet array with fast electron and ion transportation, a large electroactive surface area and an excellent structural stability. As a result, it shows a specific capacitance of 37.3 F g−1 even at a current density of 2 A g−1 and a high cycling stability with 89% retention of its initial specific capacitance after 1000 cycles in 1 M KCl solution. These results provide a way of fabricating Bi2MoO6 nanosheet arrays as efficient electrodes for electrochemical capacitors.

A branchlike MoO3/polypyrrole conductive nanocomposite was facilely prepared by wrapping a homogeneous polypyrrole (PPy) layer around MoO3 nanobelts via the in situ oxidative polymerization of a self-assembled pyrrole monomer. X-ray powder diffraction characterization demonstrated that the PPy polymer does not hinder the crystallization of the MoO3 nanobelts substrate. The electrochemical tests show that the specific capacitance of 129 F g–1 for the MoO3/PPy hybrid is higher than both pristine MoO3 and pure PPy. Moreover, the hybrid electrode with good electrical conductivity displays good cyclic stability of 90% retention after 200 cycles of charge/discharge. These results indicate a promising potential application of the MoO3/PPy nanocomposite for use as an effective electrode material in supercapacitors.Keywords: energy storage; hybrid; molybdenum trioxide; polypyrrole; supercapacitor;

•We provide a simple and operable method to prepare MoO3 nanostucture on substrate.•We prepared MoO3 nanorods on glass by magnetron sputtering and subsequent oxidation treatment.•We established the correlation between the morphologies of products and annealing temperatures.•We studied the UV–vis spectra which related to the particle size and crystalline structures.MoO3 nanorods with well-defined crystalline structure have been grown in situ on Fluorine doped Tin Oxide glass (FTO) by magnetron sputtering and subsequent oxidation treatment. Moreover, the morphologies and the crystalline structures of MoO3 products could be rationally tailored by adjusting the annealing temperature. More specifically, the calcination operated at 500 °C for 6 h leads to the formation of uniform MoO3 nanorods with an average diameter of 200 nm, and length of up to 800 nm, whereas only irregular nanoparticles or nanoplates have been obtained when the temperature was higher or lower than 500 °C.

•A novel approach for the fabrication of MoO3 nanobelts via a facile hydrothermal method was reported.•Molybdic acid was soluble in the presence of oxalic acid which played an important role for the fabrication of nanobelt.•The presence of nitric acid played a crucial role for the formation of MoO3One-dimensional MoO3 nanobelts have been synthesized for the first time from molybdic acid in a solvent of oxalic acid with the addition of nitric acid via a facile hydrothermal method. The morphology and structure of the as-prepared nanocomposite have been thoroughly characterized by the combination of different techniques. According to XRD analysis, the obtained MoO3 nanobelts are single-crystalline with an orthorhombic structure. XPS analysis proves that the Mo is in its highest oxidation state of +6. In addition, the obtained nanobelts that have a width ranging from 100 nm to 300 nm, together with a length in micrometers are observed through TEM and FESEM. Furthermore, the possible growth mechanism is also investigated.

•High dispersive orthorhombic molybdenum trioxide nanoparticles were synthesized by a facile sol–gel process.•A large amount of lithium-ions has been inserted into molybdenum trioxide host structure.•The physicochemical characterizations and the galvanostatic charge/discharge tests have been performed.•The synthesized materials exhibited superior initial discharge capacity.Highly dispersive and uniform α-MoO3 nanoparticles were successfully synthesized by a facile sol–gel method using triblock copolymer as a dispersing agent. The morphology, structure and chemical state of the product were characterized by FESEM, TEM, XRD, XPS and FT-IR. Galvanostatic charge/discharge test demonstrated high initial discharge capacities of 964 and 1192 mA h g−1 at different current densities. At a current density of 20 mA g−1, the lithium-ion insertion was up to 6.4Li+/Mo which was higher than its theoretical value. This higher embedding quantity led to higher discharge capacity, which was significant to lithium-ion battery. Moreover, the discharge curves assisted by the differential capacity curves proved that the lithium-ion intercalation/deinercalation into the α-MoO3 host structure underwent a two-step mechanism.

MoS2 microspheres with nanorods were successfully synthesized by hydrothermal method at 240 °C for 24 h, employing sodium molybdate and L-cysteine as reactants. L-cysteine turned out to be served as both the sulfur source and the directing molecule in the formation of molybdenum disulfide nanostructures. The as-prepared MoS2 was characterized by X-ray power diffraction (XRD), X-ray photoelectron spectrum (XPS), field-emission scanning electron microscopy (FE-SEM) and Fourier transform infrared spectroscopy (FT-IR). FE-SEM images showed that the product was microspheres, consisting of nanorods with length of about 100 nm. The possible formation mechanism was also discussed. The results indicated that MoO2 was the metastable phase and Na2MoO4·2H2O was converted to MoS2 via MoO2.

•The Bi2MoO6 nanosheet array film with dominant {010} facets exposed was synthesized by a facile hydrothermal reaction.•The Bi2MoO6 array provides large surface, low resistance and exposed active surface, facilitating charge separation.•The array film was further modified with ultrathin graphitic carbon nitride to enhance the photoelectrochemical activity.•The Bi2MoO6-C3N4 electrode yields a photocurrent density of 520 µA/cm2, which is nearly 300 times that of Bi2MoO6 particles.We report a facile method to fabricate Bi2MoO6 nanosheet array exposed with {010} facets for the highly improved photoelectrochemical (PEC) property related to water oxidation. The nanosheet array film would provide large surface area, low resistance and exposed oxygen atoms, facilitating the electrons transport and charge separation. More importantly, the optimized Bi2MoO6 nanosheet array yields a photocurrent density of 220 μA/cm2, which is more than two orders of magnitude higher than that of conventional Bi2MoO6 particles (1.8 μA/cm2). Additionally, the nanosheet arrays were modified with ultrathin graphitic carbon nitride (g-C3N4) nanolayers as co-catalyst to enhance the photoelectrochemical activity. As expected, this unique photoanode yields a photocurrent density of 520 μA/cm2 at +0.8 V (versus SCE) under visible light irradiation, which is 2.3 times higher than the pure Bi2MoO6 nanosheet film. The origin of enhanced photoelectrochemical activity of the co-catalyst modified film may be due to the large surface area, oriented electrons transport pathways and improved charge separation. These demonstrations clearly reveal that the rationally fabricating of high photoactive nanosheet array and coating ultrathin cocatalysts may serve an alternate strategy toward the development of highly efficient photoanodes for water splitting.

Herein, we demonstrate the synthesis of a Bi2MoO6 nanorod array followed by the deposition of a BiVO4 absorber layer. This heterojunction yielded a photocurrent density of 250 μA cm−2 at 0.8 VSCE, which is 21 times that produced by a planar Bi2MoO6 array under the same conditions. Moreover, in situ X-ray photoelectron spectroscopy clearly confirmed the improvement of the electron transport and charge separation afforded by the heterostructure, features that efficiently enhanced the photoelectrochemical properties of the array.

Novel three dimensional MoO2–graphene (MoO2–G) flower-like nanostructures are synthesized via a facile hydrothermal reaction. It has been shown that the MoO2–G demonstrates enhanced supercapacitive performance compared to pure MoO2 particles. The excellent electrochemical performance is attributed to the introduction of graphene and a hierarchical nanostructure, providing a large surface area and low equivalent series resistance.