共查询到20条相似文献,搜索用时 15 毫秒
1.
Cheng Li Tianci Fang Hong Hu Yifan Wang Xuyi Liu Sibo Zhou Junli Fu Wenzhong Wang 《Ceramics International》2021,47(8):11379-11386
Here, we first use a facile electrochemical deposition method to load Cu2O nanoparticles onto the BaTiO3 (BTO) surface to prepare BTO/Cu2O heterostructure photoanodes. Compared to the pure BTO photoanode, all BTO/Cu2O heterostructure photoanodes show outstanding visible light harvesting ability and greatly improved photoelectrochemical water splitting performance. By optimizing the loading amount of Cu2O nanoparticles, the photocurrent density achieved by BTO/Cu2O-100 photoanode is 0.26 mA/cm2 at 0 V versus Ag/AgCl, which is 2.6 times that of the bare BTO photoanode. In contrast with the photocurrent densities of the other reported BTO-based heterostructure photoanodes, the photocurrent density achieved by the present BTO/Cu2O-100 photoanode without bias voltage is much higher. Additionally, the maximum solar-to-hydrogen conversion efficiency of the BTO/Cu2O-100 heterostructure photoanode is 0.11% at 0.72 V versus reversible hydrogen electrode, approximately double that of BTO photoanode. The measurements of diffuse reflectance spectra, photoelectrochemical impedance and the room temperature photoluminescence spectra demonstrate that the improved photoelectrochemical performance contributes from the visible light absorption ability of Cu2O nanoparticles, efficient transport and separation of photogenerated electron-hole pairs, which are induced by the spontaneous polarization electric field of ferroelectric BTO, p-n junction and type-II band alignment of BTO/Cu2O heterostructure photoanode. A possible mechanism for the improved photoelectrochemical water splitting performance and charge transfer process is proposed. 相似文献
2.
Cube-like Ag/AgCl plasmonic photocatalyst was successfully synthesized through a one-pot precipitation method by simply adding an aqueous solution of AgNO3 into the natural hot spring, wherein the hot spring acted as the chlorine source. The cube-like Ag/AgCl with a size of 0.5–0.9 μm exhibited enhanced visible light photocatalytic performance for the degradation of organic MO dye due to the localized surface plasmon resonance (LSPR) of the photoexcited Ag species. The trapping experiments confirmed that O2− and h+ were the main active species during the photocatalytic process. 相似文献
3.
The Ag3PO4/Bi2WO6 hierarchical heterostructures were prepared by a combination of hydrothermal technique and in situ precipitation method for the first time. The Ag3PO4/Bi2WO6 hierarchical heterostructures displayed enhanced visible-light photocatalytic activity against phenol. The enhanced photocatalytic activity could be attributed to the effective separation of photogenerated carriers driven by the photoinduced potential difference generated at the Ag3PO4/Bi2WO6 heterojunction interface. Repetitive tests showed that the Ag3PO4/Bi2WO6 hierarchical heterostructures maintained high catalytic activity over several cycles, and it had a better regeneration capability under mild conditions. 相似文献
4.
《Ceramics International》2017,43(2):2076-2082
Novel Cd2P2O7/Ag3PO4 photocatalysts containing different mass fractions of Cd2P2O7 were synthesized by a hydrothermal method. The photocatalysts were characterized by X-ray diffractometry, transmission electron microscopy, X-ray photoelectron spectroscopy, Electron spin resonance (ESR), Fourier transform infrared spectrometry, ultraviolet–visible absorption spectroscopy and photoluminescence spectroscopy. Photocatalytic activity was decided by the effective separation and low recombination rate of photogenerated electron-hole pairs. During the experiments, the Cd2P2O7/Ag3PO4 composites possessed fierce electron- hole separation capacity. In particular, the 1 wt% Cd2P2O7/Ag3PO4 catalyst displayed higher photocatalytic performance than pure Ag3PO4 under visible-light irradiation (λ>420 nm). The ESR spectrum showed the main active species during the methyl orange degradation were ·OH and ·O2−. 相似文献
5.
《Ceramics International》2016,42(10):11827-11837
Ternary magnetic Fe3O4 nanowire@CeO2/Ag nanocomposites have been firstly synthesized by means of hydrothermal and co–precipitation techniques, and their ability to adsorb, photocatalytic degradation organic pollutants, methylene blue present in water, and separate, has been demonstrated. The results show that CeO2 and Ag nanoparticles are uniformly deposited on the surface of Fe3O4 nanowires. The photocatalytic experiments demonstrate that the Fe3O4@CeO2/Ag nanocomposites exhibit remarkably enhanced photocatalytic properties and stability compared to CeO2, CeO2/Ag, Fe3O4@CeO2, Fe3O4 under natural sunlight exposure. Moreover, excellent photocatalytic degradation efficiency for phenol and MO are also observed. The enhanced photocatalytic performance may be attributed to the synergetic effect of Fe3O4 nanowire, CeO2 and Ag nanoparticles, which lead to the enhanced light harvesting, the promoted charge separation and enhanced adsorption capacity. In addition, the Fe3O4@CeO2/Ag photocatalyst can be easily collected and separated by an external magnet. These results suggest that the nanocomposites could be exploited as potential candidates for solar photocatalysis. 相似文献
6.
《Ceramics International》2016,42(16):18605-18611
A novel AgCl/Ag/BiFeO3 photocatalyst was synthesized via an ultrasonic-assisted precipitation-photoreduction method. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), High Resolution Transmission Electron Microscopy (HRTEM), UV–vis diffuse reflectance spectroscopy (DRS) and photoluminescence emission spectra (PL) analysis were implemented to characterize the composition, morphology, structure, and optical property of the as-synthesized photocatalyst. For the decomposition of methyl orange (MO) and other organic dyes, AgCl/Ag/BiFeO3 photocatalyst manifested much superior visible-light catalytic activity than pure BiFeO3 and AgCl/Ag. Based on the trapping experiments and band structure analysis, a probable Z-scheme light catalytic mechanism was proposed. 相似文献
7.
Three-dimensional flower-like Bi2WO6 microspheres with the diameter of about 4 μm were prepared by a facile hydrothermal method using bismuth nitrate pentahydrate and sodium tungstate dihydrate as raw materials. A novel Ag-modified Bi2WO6 was synthesized through a simple and practical photoreduction process. The UV–vis diffuse reflectance spectra indicate that the Ag/Bi2WO6 samples have a significantly enhanced optical absorption in the visible light region than that of pure Bi2WO6 microspheres due to the surface plasmon resonance (SPR) of Ag nanoparticles on the surface of pure Bi2WO6. The photocatalytic activities of the as-prepared samples were evaluated by the decolorization of rhodamine B under simulated sun-light irradiation. The results reveal that the photocatalytic activities of the Ag/Bi2WO6 samples increase first and then decrease with increasing amount of loading Ag and the 1.0 wt% Ag-loaded Bi2WO6 sample exhibits the best photocatalytic activity compared with the other samples. The enhanced photocatalytic activity could be attributed to the synergistic effect of the strong SPR and the effective separation of photogenerated electrons and holes caused by Ag nanoparticles. 相似文献
8.
《Ceramics International》2017,43(6):4866-4872
A unique Cu2O/TiO2 nanocomposite with high photocatalytic activity was synthesized via a two-step chemical solution method and used for the photocatalytic degradation of organic dye. The structure, morphology, composition, optical and photocatalytic properties of the as-prepared samples were investigated in detail. The results suggested that the Cu2O/TiO2 nanocomposite is composed of hierarchical TiO2 hollow microstructure coated by a great many Cu2O nanoparticles. The photocatalytic performance of Cu2O/TiO2 nanocomposite was evaluated by the photodegradation of methylene blue (MB) under visible light, and compared with those of the pure TiO2 and Cu2O photocatalysts synthesized by the identical synthetic route. Within 120 min of reaction time, nearly 100% decolorization efficiency of MB was achieved by Cu2O/TiO2 photocatalyst, which is much higher than that of pure TiO2 (26%) or Cu2O (32%). The outstanding photocatalytic efficiency was mainly ascribed to the unique architecture, the extended photoresponse range and efficient separation of the electron-hole pairs in the Cu2O/TiO2 heterojunction. In addition, the Cu2O/TiO2 nanocomposite also retains good cycling stability in the photodegradation of MB. 相似文献
9.
《Ceramics International》2021,47(18):26063-26073
In this contribution, a Z-scheme mesoporous BiVO4/g-C3N4 nanocomposite heterojunction with a considerable surface area and high crystallinity was synthesized by a simple soft and hard template-assisted approach. This material demonstrates superior visible light-driven photocatalysis for the photoreduction of Hg(II) ions. TEM and XRD results show that the mesoporous BiVO4 NPs, with a monoclinic phase and an ellipsoid-like shape, are highly dispersed onto the porous 2D surfaces of g-C3N4 nanosheets with a particle size of 5–10 nm. The obtained BiVO4/g-C3N4 nanocomposites with a p-n heterojunction show significantly enhanced Hg(II) photoreduction efficiency compared to the mesoporous BiVO4 NPs and pristine g-C3N4. Among all synthesized photocatalysts, the 1.2% BiVO4/g-C3N4 nanocomposite indicated the highest photoreduction of Hg(II) performance, reaching ~ 100% within 60 min; this result is 3.9 and 4.5 –fold larger than that of the BiVO4 NPs and pristine g-C3N4. The Hg(II) photoreduction rates highly increase to 208.90, 314.95, 411.23 and 418.68 μmol g−1min−1 for the mesoporous 0.4, 0.8, 1.2 and 1.6% BiVO4/g-C3N4 nanocomposites, respectively. The reduction rate of the mesoporous 1.2% BiVO4/g-C3N4 nanocomposite demonstrated a 5.2 and 3.8 times larger increase than that of the pristine g-C3N4 nanosheets and pure BiVO4 NPs. The superior Hg(II) photoreduction efficiency was ascribed to decreased carrier recombination and the improved utilization of visible light by constructing BiVO4/g-C3N4 nanocomposites with a p-n junction. Transient photocurrent measurement and photoluminescence spectra were employed to confirm the possible Hg(II) photoreduction mechanism over these BiVO4/g-C3N4 photocatalysts. This research provides an accessible route for the nanoengineered design of mesoporous BiVO4/g-C3N4 heterostructures that demonstrated unique photocatalytic performance. 相似文献
10.
A series of Bi5O7I/Bi2O3 composite photocatalysts were first synthesized via chemical etching method. Their crystalline phase, composition, light absorption ability and photoluminescence emission performance were characterized by XRD, EDX, UV–vis and PL methods, respectively. And malachite green was used as the model pollutant to investigate the visible light photocatalytic activities of the composite photocatalysts. It is found that 80.48% Bi5O7I/Bi2O3 showed the highest activity for its relatively stronger absorption ability for visible light and best separation efficiency of electron–hole pairs. Last, the photocatalytic mechanism of the Bi5O7I/Bi2O3 composite was put forward qualitatively. 相似文献
11.
《Ceramics International》2016,42(3):3808-3815
SnS2/TiO2 nanocomposites have been synthesized via microwave assisted hydrothermal treatment of tetrabutyl titanate in the presence of SnS2 nanoplates in the solvent of ethanol at 160 °C for 1 h. The physical and chemical properties of SnS2/TiO2 were studied by XRD, FESEM, EDS, TEM, XPS and UV–vis diffuse reflectance spectra (DRS). The photocatalytic activity of SnS2/TiO2 nanocomposites were evaluated by photoreduction of aqueous Cr(VI) under visible light (λ>420 nm) irradiation. The experimental results showed that the SnS2/TiO2 nanocomposites exhibited excellent reduction efficiency of Cr(VI) (~87%) than that of pure TiO2 and SnS2. The SnS2/TiO2 nanocomposites were expected to be a promising candidate as effective photocatalysts in the treatment of Cr(VI) wastewater. 相似文献
12.
13.
《Ceramics International》2020,46(11):19038-19045
Waelz slag, which is a Fe-bearing hazardous waste, was applied as the raw material in the synthesis of M-Fe3O4@Fe2O3 (M = Al, Zn, Cu, and Mn) nanoparticles, which are potential photocatalysts. Through acidolysis, 97.23% of Fe and most of the valuable metals were extracted from this slag. Using sol-gel processes, designed Fe3O4@Fe2O3 nanoparticles doped with multiple elements were systematically synthesised and characterised using X-ray diffraction, field emission scanning electron microscopy, electron diffraction spectroscopy, transmission electron microscopy, and Brunauer–Emmett–Teller analysis. The photocatalytic activities of the synthesised particles and undoped Fe2O3 nanoparticles were compared through photocatalytic methyl orange degradation experiments under UV and simulated solar light. The results indicated that all of the slag-derived nanoparticles gave improved photocatalytic performances compared to the undoped sample, and the M-Fe3O4@Fe2O3 (M = Al, Zn, and Cu) sample exhibited the best photocatalytic activity. The enhancement can be attributed to grain refinement, doping, and the formation of a typical Fe3O4@Fe2O3 core-shell structure. 相似文献
14.
A novel NiTiO3/Ag3VO4 composite with type-II band alignment was prepared using a modified Pechini/precipitation method. The FESEM image of the NiTiO3/Ag3VO4 heterostructure reveals the dispersion of small NiTiO3 particles on the Ag3VO4 surfaces, indicating the close interfacial connection between NiTiO3 and Ag3VO4. The heterojunction shows remarkably higher photocatalytic activity than pure NiTiO3 and Ag3VO4 due to an increase in light harvesting efficiency and an efficient electron–hole separation being induced by the suitably matching conduction and valence band levels. Based on the VB-XPS and UV–vis DRS results, a possible electron–hole transfer mechanism at the NiTiO3/Ag3VO4 interface is proposed. 相似文献
15.
《Ceramics International》2022,48(7):9434-9441
In this study, we investigated the effect of Ag addition on the photocatalytic reactivity of TiO2 nanoparticles (NPs). Controlled amounts of Ag were incorporated in TiO2 NPs using aerosol spray pyrolysis and subsequent calcination. Ag/TiO2 composite NPs containing different amounts of Ag (e.g., 0, 0.5, 1, 2, and 5 wt%) were successfully fabricated. The photodegradation performances of the as-prepared Ag/TiO2 composite NPs were tested using methylene blue (MB) solution under UV and visible light irradiation. Upon increasing the Ag content to 1 wt%, the resulting Ag/TiO2 composite NPs exhibited increased photocatalytic reactivity due to lowered bandgap energy, which promoted both charge generation and separation. However, when the Ag content exceeded 1 wt%, the photocatalytic reactivity of the resulting Ag/TiO2 composite NPs was considerably deteriorated due to the masking effect of the excess Ag on the reactive sites of TiO2. Hence, the incorporation of an optimized amount of Ag in the TiO2 matrix promotes the photocatalytic reactivity of Ag/TiO2 composite NPs by controlling their bandgap energy and charge generation and separation processes. These results could lead to the development of photodegradation active substances for water treatment in organic solutions. 相似文献
16.
《Ceramics International》2016,42(12):13411-13420
The quest for cost-effective environmental remediation has motivated the research for highly efficient and stable photocatalysts capable of degrading pollutants under visible-light illumination. Ag-based visible-light-responsive photocatalysts demonstrate alluring properties and applications in the elimination of organic pollutants in wastewater, however they often suffer from inherent photo-corrosion under illumination. Herein, we report the facile solution-phase synthesis of silver carbonate (Ag2CO3) microcrystals with varied morphological features in different solvents. The size and morphology of Ag2CO3 materials can be tuned on the basis of varying types and ratios of solvents. The specific synthetic method allows the orientation controllable growth of Ag2CO3 microcrystals with variable length-to-diameter ratios, with the surface harvesting more solar energy, and the photocatalyst suppressing the electron-hole recombination. The enhancement in both the photocatalytic activity and photostability of Ag2CO3 catalysts is evident when AgNO3 and NaHCO3 are employed as stabilizers. Operating in the presence of 0.02 M stabilizer, the photocatalyst demonstrates highly efficient and robust degradation performance of higher than 95% in 5 successive times towards typical organic dye rhodamine B (RhB). Active holes and reactive oxygen-containing superhydroxyl radicals (·O2−) are determined by trapping experiments to be the main species responsible for improved photocatalytic performance. This work provides new insights into the development of high-performance, recyclable Ag-based photocatalytic materials for energy and environmental applications. 相似文献
17.
Aurivillius oxide semiconductors are important photocatalyst because of their unique electronic structure and layered crystal. In this paper, two kinds of Aurivillius oxide semiconductors heterostructures based on Bi4Ti3O12 nanofibers frameworks and BiOCl nanosheets are successfully synthesized by combining the electrospinning technique and solvothermal method. The high-resolution transmission electron microscopy results reveal that an intimate interface between Bi4Ti3O12 nanofibers and BiOCl nanosheets forms in the heterojunctions. Photocatalytic tests show that the BiOCl/Bi4Ti3O12 heterostructures exhibit enhanced photocatalytic activity than bare Bi4Ti3O12 and BiOCl, mainly owing to the photoinduced interfacial charge transfer based on the photosynergistic effect of the BiOCl/Bi4Ti3O12 heterojunction. At the end, the photocatalytic mechanism with O2− production was studied. 相似文献
18.
19.
20.
Ag3PO4/BiOI composites were successfully prepared by a facial room temperature liquid phase method. Ag3PO4 nanoparticles were uniformly distributed on the surface of BiOI nanosheets. The photodegradation tests show that the photocatalytic efficiency was increased at first and then decreased when further increasing Ag3PO4 content in the composites. The best photocatalytic performance was obtained for the sample with Ag/Bi ratio of 0.3 and the photodegradation efficiency of Ag3PO4/BiOI was nearly 10 times that of BiOI. The enhanced photocatalytic activity of the composites was due to the improved photogenerated carrier separation capacity, being induced by the coupling effects of the two semiconductors. 相似文献