The nanocomposite films were prepared by direct intercalation of poly(ethylene oxide) and PEO into MoO 3 xerogel via sol-gel route.The electrochromic behavior and the chemical conditions of Li + ions were investigat...The nanocomposite films were prepared by direct intercalation of poly(ethylene oxide) and PEO into MoO 3 xerogel via sol-gel route.The electrochromic behavior and the chemical conditions of Li + ions were investigated by cyclic voltammograms,UV-visible spectral transmittance and XPS.The results show that the cycling efficiency and the reversibility of insertion/extraction of Li + ions in (PEO) 1MoO 3·nH 2O nanocomposite film were improved.The intercalation of PEO into MoO 3 xerogel modulated the wavelength range of electrochromism and enhanced the electrochromic efficiency.Two different chemical conditions of Li + ions existing in the interlayer and interstitial positions of MoO 3 lattice were observed in MoO 3 xerogel and (PEO) 1MoO 3·nH 2O nanocomposite films.展开更多
Nonanethiol capped gold nanoparticles were firstly used to modify the surface of MoO 3 thin films in order to fabricate the MoO 3/Au composite thin film. Absorption experiments and XPS measurements were used to invest...Nonanethiol capped gold nanoparticles were firstly used to modify the surface of MoO 3 thin films in order to fabricate the MoO 3/Au composite thin film. Absorption experiments and XPS measurements were used to investigate the effect of Au nanoparticles on the photochromic properties of the composite thin film. According to the XPS measurements, the binding energy for the valence band(O 2p ) of the composite thin films decreased. The experimental results of absorbance showed that the photochromic efficiency for the composite thin films became at least as two times as that of MoO 3 thin films. The mechanism of enhancement can be explained by the band energy theory of semiconductor. The Schottky barrier formed at the interface prolonged the electron hole pair separation lifetime and resulted in the enhancement of the photochromic efficiency.展开更多
The restacking hindrance of MXene films restricts their development for high volumetric energy density of flexible supercapacitors toward applications in miniature,portable,wearable or implantable electronic devices.A...The restacking hindrance of MXene films restricts their development for high volumetric energy density of flexible supercapacitors toward applications in miniature,portable,wearable or implantable electronic devices.A valid solution is construction of rational heterojunction to achieve a synergistic property enhancement.The introduction of spacers such as graphene,CNTs,cellulose and the like demonstrates limited enhancement in rate capability.The combination of currently reported pseudocapacitive materials and MXene tends to express the potential capacitance of pseudocapacitive materials rather than MXene,leading to low volumetric capacitance.Therefore,it is necessary to exploit more ideal candidate materials to couple with MXene for fully expressing both potentials.Herein,for the first time,high electrochemically active materials of ultrathin MoO3 nanobelts are intercalated into MXene films.In the composites,MoO3 nanobelts not only act as pillaring components to prevent restacking of MXene nanosheets for fully expressing the MXene pseudocapacitance in acidic environment but also provide considerable pseudocapacitive contribution.As a result,the optimal M/MoO3 electrode not only achieves a breakthrough in volumetric capacitance(1817 F cm-3 and 545 F g-1),but also maintains good rate capability and excellent flexibility.Moreover,the corresponding symmetric supercapacitor likewise shows a remarkable energy density of 44.6 Wh L-1(13.4 Wh kg-1),rendering the flexible electrode a promising candidate for application in high-energy-density energy storage devices.展开更多
A 10-nm-thick molybdenum tri-oxide(MoO3) thin film was used as the interconnector layer in tandem organic lightemitting devices(OLEDs).The tandem OLEDs with two identical emissive units consisting of N,N-bis(naph...A 10-nm-thick molybdenum tri-oxide(MoO3) thin film was used as the interconnector layer in tandem organic lightemitting devices(OLEDs).The tandem OLEDs with two identical emissive units consisting of N,N-bis(naphthalen-1-yl)N,N-bis(phenyl)-benzidine(NPB) /tris(8-hydroxyquinoline) aluminum(Alq3) exhibited current efficiency-current density characteristics superior to the conventional single-unit devices.At 20 mA/cm2,the current efficiency of the tandem OLEDs using the interconnector layers of MoO3 thin film was about 4.0 cd/A,which is about twice that of the corresponding conventional single-unit device(1.8cd/A).The tandem OLED showed a higher power efficiency than the conventional single-unit device for luminance over 1200cd/m2.The experimental results demonstrated that a MoO3 thin film with a proper thickness can be used as an effective interconnector layer in tandem OLEDs.Such an interconnector layer can be easily fabricated by simple thermal evaporation,greatly simplifying the device processing and fabrication processes required by previously reported interconnector layers.A possible explanation was proposed for the carrier generation of the MoO3 interconnector layer.展开更多
The films of photocatalysts have been widely used in decomposition pollutants. In this study, the films were successfully prepared from Bi2MoO6 and g-C3N4/Bi2MoO6 by a simple method, respectively. The samples were cha...The films of photocatalysts have been widely used in decomposition pollutants. In this study, the films were successfully prepared from Bi2MoO6 and g-C3N4/Bi2MoO6 by a simple method, respectively. The samples were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), Fourier transform infrared spectroscopy(FTIR), photoluminescence(PL), UV-Vis diffuse reflectance spectroscopy(DRS) and electrochemical experiments to investigate crystalline structure, morphology, composition and properties. The photocatalytic activity of the photocatalyst films for the pollutants was evaluated by degradation of methylene blue(MB) in aqueous solution under visible light irradiation. Experiments revealed that the film of g-C3Na/Bi2MoO6 exhibited higher photocatalytic ability compared to the single-component photocatalyst, and proved its stability. The superior catalytic performance can be attributed to the effective separation of electron-hole pairs and the reduced rate of recombination. This work is of great value for the preparation of photocatalysts films.展开更多
文摘The nanocomposite films were prepared by direct intercalation of poly(ethylene oxide) and PEO into MoO 3 xerogel via sol-gel route.The electrochromic behavior and the chemical conditions of Li + ions were investigated by cyclic voltammograms,UV-visible spectral transmittance and XPS.The results show that the cycling efficiency and the reversibility of insertion/extraction of Li + ions in (PEO) 1MoO 3·nH 2O nanocomposite film were improved.The intercalation of PEO into MoO 3 xerogel modulated the wavelength range of electrochromism and enhanced the electrochromic efficiency.Two different chemical conditions of Li + ions existing in the interlayer and interstitial positions of MoO 3 lattice were observed in MoO 3 xerogel and (PEO) 1MoO 3·nH 2O nanocomposite films.
文摘Nonanethiol capped gold nanoparticles were firstly used to modify the surface of MoO 3 thin films in order to fabricate the MoO 3/Au composite thin film. Absorption experiments and XPS measurements were used to investigate the effect of Au nanoparticles on the photochromic properties of the composite thin film. According to the XPS measurements, the binding energy for the valence band(O 2p ) of the composite thin films decreased. The experimental results of absorbance showed that the photochromic efficiency for the composite thin films became at least as two times as that of MoO 3 thin films. The mechanism of enhancement can be explained by the band energy theory of semiconductor. The Schottky barrier formed at the interface prolonged the electron hole pair separation lifetime and resulted in the enhancement of the photochromic efficiency.
基金supported by Major Science and Technology Projects of Heilongjiang Province(2019ZX09A01)National Key Technology R&D Program(Grant No.2017YFB1401805)+1 种基金the China Postdoctoral Science Foundation(2019T120285,2018M641884)Heilongjiang Province Postdoctoral Science Foundation(LBH-Z18235)。
文摘The restacking hindrance of MXene films restricts their development for high volumetric energy density of flexible supercapacitors toward applications in miniature,portable,wearable or implantable electronic devices.A valid solution is construction of rational heterojunction to achieve a synergistic property enhancement.The introduction of spacers such as graphene,CNTs,cellulose and the like demonstrates limited enhancement in rate capability.The combination of currently reported pseudocapacitive materials and MXene tends to express the potential capacitance of pseudocapacitive materials rather than MXene,leading to low volumetric capacitance.Therefore,it is necessary to exploit more ideal candidate materials to couple with MXene for fully expressing both potentials.Herein,for the first time,high electrochemically active materials of ultrathin MoO3 nanobelts are intercalated into MXene films.In the composites,MoO3 nanobelts not only act as pillaring components to prevent restacking of MXene nanosheets for fully expressing the MXene pseudocapacitance in acidic environment but also provide considerable pseudocapacitive contribution.As a result,the optimal M/MoO3 electrode not only achieves a breakthrough in volumetric capacitance(1817 F cm-3 and 545 F g-1),but also maintains good rate capability and excellent flexibility.Moreover,the corresponding symmetric supercapacitor likewise shows a remarkable energy density of 44.6 Wh L-1(13.4 Wh kg-1),rendering the flexible electrode a promising candidate for application in high-energy-density energy storage devices.
基金Project supported by the Doctoral Foundation of the Ministry of Education of China (Grant No. 20100171110025)the State Key Laboratory of Optoelectronic Materials and Technologies,China (Grant No. 2010-RC-3-1)the Fundamental Research Funds for the Central Universities,China (Grant No. 09lgpy25)
文摘A 10-nm-thick molybdenum tri-oxide(MoO3) thin film was used as the interconnector layer in tandem organic lightemitting devices(OLEDs).The tandem OLEDs with two identical emissive units consisting of N,N-bis(naphthalen-1-yl)N,N-bis(phenyl)-benzidine(NPB) /tris(8-hydroxyquinoline) aluminum(Alq3) exhibited current efficiency-current density characteristics superior to the conventional single-unit devices.At 20 mA/cm2,the current efficiency of the tandem OLEDs using the interconnector layers of MoO3 thin film was about 4.0 cd/A,which is about twice that of the corresponding conventional single-unit device(1.8cd/A).The tandem OLED showed a higher power efficiency than the conventional single-unit device for luminance over 1200cd/m2.The experimental results demonstrated that a MoO3 thin film with a proper thickness can be used as an effective interconnector layer in tandem OLEDs.Such an interconnector layer can be easily fabricated by simple thermal evaporation,greatly simplifying the device processing and fabrication processes required by previously reported interconnector layers.A possible explanation was proposed for the carrier generation of the MoO3 interconnector layer.
基金Supported by the National Natural Science Foundation of China(No.21276036), the National Key Technology Support Program of China(No.2014BAB 12B06), the Program for Liaoning Excellent Talents in University, China(No.LJQ2015013) and the Fundamental Research Funds for the Central Universities, China(Nos.3132014323, 3132015085).
文摘The films of photocatalysts have been widely used in decomposition pollutants. In this study, the films were successfully prepared from Bi2MoO6 and g-C3N4/Bi2MoO6 by a simple method, respectively. The samples were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), Fourier transform infrared spectroscopy(FTIR), photoluminescence(PL), UV-Vis diffuse reflectance spectroscopy(DRS) and electrochemical experiments to investigate crystalline structure, morphology, composition and properties. The photocatalytic activity of the photocatalyst films for the pollutants was evaluated by degradation of methylene blue(MB) in aqueous solution under visible light irradiation. Experiments revealed that the film of g-C3Na/Bi2MoO6 exhibited higher photocatalytic ability compared to the single-component photocatalyst, and proved its stability. The superior catalytic performance can be attributed to the effective separation of electron-hole pairs and the reduced rate of recombination. This work is of great value for the preparation of photocatalysts films.