- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Novel in-situ radiation construction of thioglycollic acid capped CdS quantum dots functionalized g-C3N4 nanohybrids with superior photocatalytic activity under visible light
摘要： A novel type of thioglycollic acid (TGA) capped CdS QDs functionalized g-C3N4 nanohybrids was prepared successfully by in-situ electron beam radiation at room temperature. When the radiation dose was chosen to be 10 kGy, the concentration of CdCl2 was 0.5 mmol/L and the optimum ratio of TGA to CdCl2 was 3 : 1 at pH = 9.0, the TGA-CdS QDs/g-C3N4 nanohydrids had the highest degradation rate at the modified TGA-CdS QDs content of 3.0 wt % and the removal rate of TGA-CdS QDs/g-C3N4 on the dye of MO was reached 94.7% in less than 20 min. The introduction of TGA-CdS QDs was confirmed successfully by a series of morphologies and structures of characterization and analysis with UV–vis, FL, Inverted-FL, DRS, FTIR, XRD, XPS, FE-SEM and HR-TEM, etc. After the introduction of TGA-CdS QDs into the surfaces of g-C3N4, the recombination of photo-generated electron-hole pairs can be significantly reduced and the photocatalytic activity and photostability can be also improved. It is favorable to enhance the photocatalytic performance for the photo-generated holes are rapidly transferred to the solution and hindered the photo-corrosion of TGA-CdS QDs.
关键词： Thioglycollic acid,Electron beam radiation,g-C3N4,Photocatalytic,Quantum dots
更新于2025-09-16 10:30:52
-
Large-scale synthesis of crystalline g-C <sub/>3</sub> N <sub/>4</sub> nanosheets and high-temperature H <sub/>2</sub> sieving from assembled films
摘要： Poly(triazine imide) (PTI), a crystalline g-C3N4, hosting two-dimensional nanoporous structure with an electron density gap of 0.34 nm, is highly promising for high-temperature hydrogen sieving because of its high chemical and thermal robustness. Currently, layered PTI is synthesized in potentially unsafe vacuum ampules in milligram quantities. Here, we demonstrate a scalable and safe ambient pressure synthesis route leading to several grams of layered PTI platelets in a single batch with 70% yield with respect to the precursor. Solvent exfoliation under anhydrous conditions led to single-layer PTI nanosheets evidenced by the observation of triangular g-C3N4 nanopores. Gas permeation studies confirm that PTI nanopores can sieve He and H2 from larger molecules. Last, high-temperature H2 sieving from PTI nanosheet–based membranes, prepared by the scalable filter coating technique, is demonstrated with H2 permeance reaching 1500 gas permeation units, with H2/CO2, H2/N2, and H2/CH4 selectivities reaching 10, 50, and 60, respectively, at 250°C.
关键词： PTI,high-temperature,nanosheets,crystalline g-C3N4,hydrogen sieving
更新于2025-09-16 10:30:52
-
Strongly Coupled Amorphous Porous NbO <sub/>x</sub> (OH) <sub/>y</sub> /g‐C <sub/>3</sub> N <sub/>4</sub> Heterostructure Composite for Efficient Photocatalytic Hydrogen Evolution
摘要： Heterostructure composites are promising materials in photocatalytic hydrogen evolution due to their advantage on promoting photogenerated carrier separation efficiently. However, the weak interfacial interaction can block electron transfer and complicate synthesis methods restrict the practical application of catalysts. Here, we report an interfacial enhanced amorphous porous NbOx(OH)y/g-C3N4 heterostructure composite through a spontaneous coupling process. It was characterized by XRD, TEM, FT-IR, XPS, NH3-TPD and CO2-TPD, etc., which demonstrated that NbOx(OH)y possess amorphous porous structures with high specific surface area (205 m2/g) and plenty of acidic sites (418 μmol/g) as well as basic sites (184 μmol/g) contributed from uncoordinated Nb and -OH. These acidic and basic sites electrostatically attract -NHx and C-OH on the surface of g-C3N4 to form hydrogen bonds (Nb-O-H???NH2, Nb-O???H-O-C), showing a strong electron interaction between NbOx(OH)y and g-C3N4. When tested as a photocatalyst for water splitting under visible light, the optimal NbOx(OH)y/CN-0.05 heterostructure composite exhibits a hydrogen evolution rate of 53 μmol/g/h, which is about 14 times higher than that of g-C3N4 (3.8 μmol/g/h) and is even superior than P25 (16 μmol/g/h). These present findings lay a foundation for the synthesis of strongly interacting heterogeneous composites.
关键词： heterojunction,water splitting,amorphous niobium oxide,photocatalysis,g-C3N4
更新于2025-09-12 10:27:22
-
Enhanced photoelectrochemical performance of NaNbO3 nanofibers photoanode coupled with visible-light active g-C3N4 nanosheets for water splitting
摘要： Sodium niobate nanofibers (NaNbO3-NF) have been synthesized by hydrothermal technique and further coupled with visible light responsive graphitic carbon nitride (g-C3N4) nanosheets in the different concentration ratio of 2:1 (2-CN), 4:1 (4-CN) and 8:1 (8-CN). A significant improvement in the photoelectrochemical (PEC) performance of g-C3N4/NaNbO3-NF (4-CN) nanostructured photoanode as compared to bare NaNbO3 photoanode is observed. A current density of 12.55 mA cm?2 at 1 V with respect to Ag/AgCl reference electrode is achieved for g-C3N4/NaNbO3-NF (4-CN) photoanode which is ~3 times higher than the NaNbO3-NF photoanode. Also, as compared to NaNbO3-NF, g-C3N4/NaNbO3-NF (4-CN) nanocomposite photoanode showed ~3 times improvement in the incident photon-to-current conversion efficiency. The improvement in the PEC performance of visible light active g-C3N4/NaNbO3-NF (4-CN) nanocomposite is attributed to the improved photoresponse of NaNbO3-NF due to the coupling of g-C3N4 and formation of type-II heterojunction between them leading to the enhanced separation of the photogenerated charge carriers. A possible reaction mechanism for the improved photoelectrochemical water splitting performance has been proposed for g-C3N4/NaNbO3-NF (4-CN) photoanode.
关键词： Photoelectrode,Nanocomposite,Heterojunction,g-C3N4/NaNbO3-NF,PEC Water Splitting
更新于2025-09-12 10:27:22
-
Sono-photodeposition of Ag over sono-fabricated mesoporous Bi2Sn2O7-two dimensional carbon nitride: Type-II plasmonic nano-heterojunction with simulated sunlight-driven elimination of drug
摘要： The mesoporous Ag/Bi2Sn2O7-C3N4 plasmonic nanophotocatalyst, which synthesized by the hybridization method of sono-dispersion and heat-treatment following with the sono-photodeposition, was applied as an efficient solar-light-driven photocatalyst for degradation of Tetracycline (TC) antibiotic. Also, the Bi2Sn2O7, g-C3N4, Bi2Sn2O7-C3N4, Ag/Bi2Sn2O7 and Ag/C3N4 nanophotocatalysts were synthesized to compare. The characterizations of samples were conducted using XRD, morphology analyses such as FESEM, TEM and AFM, EDX and dot mapping, BET-BJH, FTIR, DRS and pHpzc. The results of morphology analyses showed that about 75.2% of nanoparticles are at the range of 10-20 nm and the minimum and maximum particle sizes were 6.9 nm and 42.2 nm respectively. Moreover, the cubic Ag particles size was about 25.7 nm. Besides, the results of the UV-vis diffuse reflectance spectroscopy analysis illustrated the promotion of the absorption edge of Ag/Bi2Sn2O7-C3N4 (at about 521nm) following with the decrement of band gap (2.38 eV). The photocatalytic activity of Ag/Bi2Sn2O7-C3N4 was obtained higher than other samples (89.1%) due to Bi2Sn2O7-C3N4 type-II heterojunction, porous structure with high specific surface area (66 m2/g) owing to the usage of ultrasonic energy and surface plasmon resonance created using the Ag particle. Moreover, experiments were carried out to investigate the effect of various parameters such as the photocatalyst dosage, initial concentration and pH of TC solution in removing the contaminate molecule from aqueous solution under the light illumination, which was simulated as sunlight, in the presence of photocatalyst and the possible elimination mechanism was proposed for pollutant removal.
关键词： Sono-Hydrothermal,Solar-Light-Driven,Photo-Deposition,Ag/Bi2Sn2O7-C3N4 Nanophotocatalyst,Tetracycline Degradation
更新于2025-09-12 10:27:22
-
Ti3C2 MXene-derived carbon-doped TiO2 coupled with g-C3N4 as the visible-light photocatalysts for photocatalytic H2 generation
摘要： Photocatalytic hydrogen production is a fascinating clean energy technology to solve the environmental issues and energy crisis. Herein, Ti3C2, a member of MXene, is successfully designed as a precursor for preparing C-TiO2/g-C3N4 photocatalyst without extra carbon addition, and the C-TiO2/g-C3N4 photocatalysts exhibit drastically improved photocatalytic hydrogen generation activity. When the mass ratio of Ti3C2 to g-C3N4 is 10 wt% in the composite, the prepared C-TiO2/g-C3N4 composite photocatalyst shows the highest photocatalytic H2 production activity as high as of 1409 μmol/h/g, which is about 8 times and 24 times higher than the activity of pure g-C3N4 and C-TiO2, respectively. The possible mechanism is assumed that the achieved intimate heterojunction between the Ti3C2 MXene-derived C-doped TiO2 and g-C3N4 can efficiently facilitate the photogenerated charge transfer and inhibit the recombination of electronics and holes, which markedly enhanced photocatalytic hydrogen production activity of C-TiO2/g-C3N4 photocatalysts under visible light.
关键词： MXene,Carbon-doped TiO2,Photocatalyst,Hydrogen production,g-C3N4
更新于2025-09-12 10:27:22
-
Mesoporous g-C3N4 ultrathin nanosheets coupled with QDs self-decorated SnIn4S8 homojunctions towards highly efficient photocatalytic functional transformation
摘要： In this research, we rationally designed and synthesized quantum dots self-decorated SnIn4S8/g-C3N4 (QDs-SISCN) nanocomposites by in situ anchoring quantum dot (QDs) self-decorated SnIn4S8 (SIS) nanosheets onto the surface of mesoporous graphite carbon nitride (CN) nanosheets in a mixed solvothermal environment. The photoreduction of 4-nitroaniline (4-NA) was used to assess their photocatalytic activity. In this framework, the construction of CN nanosheets-supported QDs-decorated SIS homojunctions can integrate the advantages of both homojunctions and heterojunctions. Benefiting from those favourable properties, the QDs-SISCN nanocomposites exhibit superior photocatalytic activity towards 4-NA reduction under visible-light irradiation (l > 400) as a result of the optimizied amount of CN nanosheets added. The recycling experiments also reveal high stability of the QDs-SISCN nanocomposites during photocatalytic reactions for 4-NA reduction. Moreover, the investigation of the photocatalytic mechanism from systematic characterizations, including measurements of the photocurrent response, electrochemical impedance spectroscopy (EIS) and photoluminescence (PL) indicate that the improved separation efficiency of charge carriers is a critical parameter for the enhanced photocatalytic activity for 4-NA reduction. We expect this research to provide a promising path to the design and synthesis of highly efficient hybrid photocatalysts for functional-group transformations.
关键词： Photocatalyst,SnIn4S8,g-C3N4,Quantum dots
更新于2025-09-12 10:27:22
-
Facile constructing plasmonic Z-scheme Au NPs/g-C3N4/BiOBr for enhanced visible light photocatalytic activity
摘要： A novel ternary Au NPs/g-C3N4/BiOBr Z-scheme heterojunction composite was fabricated through hydrothermal and in-situ reduction method, and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, ultraviolet-visible diffuse reflection spectroscopy and photoluminescence emission spectroscopy. The photocatalytic activity was evaluated by the degradation of phenol under visible-light irradiation. It was found that Au NPs/g-C3N4/BiOBr showed enhanced photocatalytic activity, which is 3-fold higher than g-C3N4 and 2.5-fold higher than BiOBr. This could be attributed to the effective separation of photogenerated electron-hole pairs, narrowed band gap (2.10 eV) and surface plasmon resonance (SPR).
关键词： Au NPs/g-C3N4/BiOBr,Z-scheme,phenol,visible-light photocatlysis,plasmon
更新于2025-09-12 10:27:22
-
Enhanced photocatalytic hydrogen evolution over TiO2/g-C3N4 2D heterojunction coupled with plasmon Ag nanoparticles
摘要： 2D heterojunction based on g-C3N4 nanosheets with other semiconductor nanosheets is a promising way to improve photocatalytic hydrogen evolution (PHE) activity over g-C3N4. However, current 2D heterojunction based on g-C3N4 are unsatisfactory due to their insu?cient absorption of visible light and ine?cient charge separation. In this work, Ag/TiO2/g-C3N4 nanocomposites based on 2D heterojunction coupling with Ag surface plasmon resonance (SPR) were synthesized by a method combining facile wetness impregnation calcination. The PHE activity of Ag/TiO2/g-C3N4 nanocomposites is attributed to the TiO2/g-C3N4 2D heterojunction and bare g-C3N4 nanosheet under visible light irradiation, indicating a cooperative e?ect between Ag and TiO2/g-C3N4 2D heterojunction. As a result of SPR e?ect, the composites strongly absorb visible light. In addition, the oscillating hot electrons from Ag can easily transfer to 2D heterojunction. This synergistic e?ect lead to su?cient visible light absorption and e?cient charge separation of 2D heterojunction, which improved the PHE activity of g-C3N4. This work indicates that loading metal nanoparticles on 2D heterojunction as metal SPR-2D heterojunction nanocomposites may be a potential method for harvesting visible light for PHE.
关键词： Surface plasmon resonance,Photocatalytic hydrogen evolution,TiO2,2D heterojunction,g-C3N4
更新于2025-09-12 10:27:22
-
Three dimensional Pt island-on-Au architectures coupled with graphite carbon nitride nanosheets for effective photo-accelerated methanol electro-oxidation
摘要： Two dimensional (2D) visible-light-activated graphite carbon nitride (CN) nanosheets were used to deposit the traditional electrocatalyst of Pt and Au through a facile one-pot hydrothermal approach. By adjusting different amount of Pt and Au, 3D Pt island-on-Au architectures were formed on the surface of CN nanosheets (Pt-Au/CN). The obtained Pt-Au/CN composite was used for electrocatalytic methanol oxidation reaction (MOR). Comparing with Pt/CN modified electrode, Pt-Au/CN exhibited 13.8 times enhancement on the electrocatalytic activity of MOR. Interestingly, when Pt-Au/CN composite was illuminated with visible light, the current density and stability were continuously enhanced by evaluating of cyclic voltammetry (CV), chronopoenttiometric (CP), chronoamperometry (CA), and electrochemical impedance spectra (EIS). The bimetallic electronic effects of Pt and Au; 3D Pt islands-on-Au architectures; 2D support nanosheet of CN, and the synergistic effect of photo- and electro-catalytic processes resulted in the improved electrocatalytic activity and stability. The present investigations provide a promising future to construct highly efficient electrocatalyst by combining bimetal on semiconductor support and with the assistance of visible light irradiation.
关键词： visible light,g-C3N4 nanosheet,methanol oxidation,photo-accelerated electrocatlysis,Pt island-on-Au architectures
更新于2025-09-12 10:27:22