- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Controlled Synthesis of Mesoporous Single-Crystalline TiO2 Nanoparticles for Efficient Photocatalytic H2 Evolution
摘要： Mesoporous single-crystals have emerged as a unique family of functional materials, exhibiting excellent performance in various applications, owing to their well-defined accessible mesoporosity and highly single-crystalline structures. Precise tailoring structures of mesoporous single-crystals at the nanoscale remains an unsolved scientific and technical challenge. Herein, we report a facile and general approach for the synthesis of mesoporous single-crystalline TiO2 nanoparticles (designated as MSC-TNs) with distinctive traits including tunable morphologies, controllable particle sizes, well dispersity, high hydrophilicity, well-defined mesoporosity and single-crystal nature. Specifically, the amount of water employed in the precursor solution was seen to give fine control over the particle sizes and morphologies of MSC-TNs. MSC-TNs with different sizes show excellent photocatalytic activity in production of hydrogen from water. Under the illumination of 300 W Xe lamp, MSC-TNs were shown to provide good photodegradation performance with Rhodamine 6G, as well as H2 production when loaded 1 wt % Pt. In a CH3OH solution H2 was evolved with a rate of 8.98 mmol h-1 g-1, which is significantly higher than with commercial P25 nanoparticles (4.02 mmol h-1 g-1).
关键词： Water Purification,Photodegradation,Photocatalysis,TiO2,Mesoporous
更新于2025-09-23 15:21:01
-
Defect engineered mesoporous 2D graphitic carbon nitride nanosheet photocatalyst for Rhodamine B degradation under LED light illumination
摘要： In this work, a nitrogen vacancy induced 2D mesoporous graphitic carbon nitrogen (g-C3N4) nanosheet photocatalyst was successfully synthesized through a simple two step thermal treatment method. The morphology of the nanosheet photocatalyst and the presence of nitrogen vacancy was explored through a wide range of characterization techniques. The as prepared photocatalyst possess an improved visible light absorption efficiency as confirmed from the UV-Visible diffuse reflectance spectroscopy (DRS). Moreover, the improved charge carrier separation efficiency of the nitrogen vacant material was demonstrated from the photoluminescence spectrum. Most importantly, the photocatalyst exhibited an excellent photodegradation efficiency towards rhodamine B (RhB) dye under the illumination of an 18 W LED light. The vacancy induced nanosheets demonstrated a degradation co-efficient of 0.074 min-1 in RhB degradation, which is 9.25 fold higher than that of the bulk g-C3N4. The nanosheets further exhibited an enhanced degradation efficiency toward tetracycline antibiotic. Furthermore, the photocatalyst displayed an outstanding stability even after 5 cycles. A plausible photocatalytic mechanism has also been explained based on the results obtained from the radical scavenging experiments. This study would provide insight into the defect induction mechanism into the 2D g-C3N4 nanosheet and expected to help in rationally designing vacancy induced materials with cost effective application in various environmental fields.
关键词： nitrogen vacancy,LED light irradiation,rhodamine B,mesoporous,2D g-C3N4 nanosheet
更新于2025-09-23 15:21:01
-
Using soft polymer template engineering of mesoporous TiO <sub/>2</sub> scaffolds to increase perovskite grain size and solar cell efficiency
摘要： The mesoporous (meso)-TiO2 layer is a key component of high efficiency perovskite solar cells (PSCs). Herein, pore size controllable meso-TiO2 layers are prepared using spin coating of commercial TiO2 nanoparticle (NP) paste with added soft polymer templates (SPT) followed by removal of the SPT at 500 °C. The SPTs consist of swollen crosslinked polymer colloids (microgels, MGs) or a commercial linear polymer (denoted as LIN). The MGs and LIN were comprised of the same polymer, which was poly(N-isopropylacrylamide) (PNIPAm). Large (L-MG) and small (S-MG) MG SPTs were employed to study the effect of template size. The SPT approach enabled pore size engineering in one deposition step. The SPT/TiO2 nanoparticle films had pore sizes > 100 nm; whereas, the average pore size was 37 nm for the control meso-TiO2 scaffold. The largest pore sizes were obtained using L-MG. SPT engineering increased the perovskite grain size in the same order as the SPT sizes: LIN < S-MG < L-MG and these grain sizes were larger than obtained using the control. The power conversion efficiencies (PCEs) of the SPT/TiO2-devices were ~ 20% higher than that for the control meso-TiO2 device and the PCE of the champion S-MG device was 18.8%. The PCE improvement is due to the increased grain size and more effective light harvesting of the SPT devices. The increased grain size was also responsible for the improved stability of the SPT/TiO2 devices. The SPT method used here is simple, scalable and versatile and should also apply to other PSCs.
关键词： Perovskite solar cells,template engineering,mesoporous TiO2,porosity,microgel,grain size.
更新于2025-09-23 15:21:01
-
One-pot fabrication of mesoporous g-C3N4/NiS co-catalyst counter electrodes for quantum-dot-sensitized solar cells
摘要： The nickel sulfide (NiS) nanoparticles were anchored on the mesoporous graphitic carbon nitride (g-C3N4) by one-pot calcination with sulfur powder as sulfur source and pore-forming agent. It is the first attempt to use the g-C3N4/NiS as a counter electrode (CE) for quantum-dot-sensitized solar cells. The g-C3N4/NiS co-catalyst based on 0.74 wt% NiS loading for Sn2- reduction obtained a low interface charge transfer resistance (Rct) of 1.08 Ω. The power conversion efficiency of the QDSSC assembled with ZnSe/CdS/CdSe/ZnSe-sensitized TiO2 photoanode and g-C3N4/NiS CE is up to 5.64%, which is 3.05 times as high as that of pure g-C3N4 CE. The enhancement of cell efficiency is attributed to the synergistic effects of excellent morphology of g-C3N4 and its co-catalysis with NiS nanoparticles. The mesoporous architecture contributes a large specific surface area and fast electrolyte transfer channels, and the coupling of g-C3N4 with NiS promotes the transfer of charge between the interface g-C3N4/NiS and electrolytes. The presented strategy for fabricating mesoporous architecture with g-C3N4/NiS uses low-cost raw materials and a simple preparation method, which provides a feasible route to enhance the electrocatalytic activity of g-C3N4.
关键词： g-C3N4/NiS,electrocatalytic activity,mesoporous architecture,counter electrode,quantum-dot-sensitized solar cells
更新于2025-09-23 15:21:01
-
A comprehensive study on the enhanced photocatlytic activity of a double-shell mesoporous plasmonic Cu@Cu2O/SiO2 as a visible-light driven nanophotocatalyst
摘要： A novel sunlight-activated double-shell Cu@Cu2O/SiO2 (m-pCu@Cu2O/SiO2) photocatalyst is presented via a combined precipitation and sol-gel methods with a mesoporous silica outer shell. After applying several characterization techniques on the m-pCu@Cu2O/SiO2, it was tested in the photodegradation of ciprofloxacin (CIP). The experimental results demonstrated a higher photocatalytic activity of the double-shell m-pCu@Cu2O/SiO2 nanophotocatalyst than the core-shell pCu@Cu2O nanophotocatalyst under the sunlight irradiation. When the content of pCu@Cu2O was 30 wt.%, it showed the highest activity. The Cu nanoparticles exhibited the surface plasmonic resonance (SPR) effect which increased the light absorption in the visible region of light. It also caused the rapid separation of the photoexcited e?/h+ pairs. Furthermore, the mesoporous structure of outer shell silica favors the transfer of reactants, resulting in the improved photoactivity performance for the supported pCu@Cu2O catalyst. Central composite design (CCD) based on RSM (response surface methodology) approach was used to optimize four of the most important experimental variables. The photodegraded intermediates were identified by HPLC-Mass.
关键词： Plasmonic,Response surface methodology,Ciprofloxacin,Mesoporous,Double-shell,Nanophotocatalyst
更新于2025-09-23 15:21:01
-
Ambient air-processed mesoscopic solar cells based on methylammonium and phenethylammonium quasi-2D/3D perovskites
摘要： The instability of perovskite solar cells under ambient conditions leads many scientific groups to produce their solar cell devices under controllable, yet, expensive conditions. In this work, a mesoscopic solar cell device produced under ambient air/temperature conditions and relatively high humidity is presented. The active material is based on methylamine, phenethylamine, lead(II) iodide and lead(II) chloride. Furthermore, a bis(trifluoromethane)sulfonimide lithium (Li-TFSI) salt layer was used as a dopant onto mesoscopic TiO2, while the hole-transport material used was the popular poly(3-hexylthiophene-2,5-diyl) (P3HT) polymer. All layers were deposited by simple spin coating technique, while the whole process took place under 40–60% relative humidity–ambient conditions. The sequential deposited perovskite layer was built by a 3D mixed halide (CH3NH3)3PbI3Cl2 layer on top of a mixed 3D/Quasi-2D perovskite (CH3NH3)3PbI3Cl2–(C8H9NH3)2(CH3NH3)2Pb3I10 layer. These specific perovskites were used to take advantage of the well-known power conversion efficiency (PCE) of the mixed halide perovskite based on methylamine, and the proven reproducibility and stability of the phenethylamine-based perovskites, especially under non-controllable conditions. The champion mesoscopic device presented a PCE of 13.22%, with short circuit current density (JSC) of 23.67 mA/cm2, open circuit voltage (VOC) of 1034 mV and fill factor (FF) 0.54.
关键词： Mesoscopic structure,Methylamine–phenethylamine mixed cations,Hybrid organic–inorganic semiconductors,Ambient conditions,Perovskites,Mesoporous solar cells
更新于2025-09-23 15:21:01
-
Surface Plasmon Resonance-Enhanced Visible-NIR-Driven Photocatalytic and Photothermal Catalytic Performance by Ag/Mesoporous Black TiO2 Nanotubes Heterojunctions
摘要： Ag/mesoporous black TiO2 nanotubes heterojunctions (Ag-MBTHs) are fabricated through surface hydrogenation, wet-impregnation and photoreduction strategy. The as-prepared Ag-MBTHs possess a relatively high specific surface area of ~85 m2 g-1 and an average pore size of ~13.2 nm. The Ag-MBTHs with narrow bandgap of ~2.63 eV extend the photoresponse from UV to visible light and near-infrared (NIR) region, which exhibit excellent visible-NIR-driven photothermal catalytic and photocatalytic performance for complete conversion nitro aromatic compounds (100%) and mineralization of high-toxic phenol (100%). The enhancement can be attributed to the mesoporous hollow structures increasing the light multi-refraction, the Ti3+ in frameworks and the surface plasmon resonance (SPR) effect of plasmonic Ag nanoparticles favoring light-harvesting and spatial separation of photogenerated electron-hole pairs, which is confirmed by transient fluorescence. The fabrication of this novel SPR-enhanced visible-NIR-driven Ag-MBTHs catalyst may provide new insights for designing other high-performance heterojunctions photocatalytic and photothermal catalytic nanomaterials.
关键词： mesoporous black TiO2 nanotube,photothermal catalysis,surface plasmon resonance,Photocatalysis,heterojunction
更新于2025-09-23 15:21:01
-
Tunable Chromaticity and High Color Rendering Index of WLEDs with CaAlSiN <sub/>3</sub> :Eu <sup>2+</sup> and YAG:Ce <sup>3+</sup> Dual Phosphora??ina??silicaa??glass
摘要： Phosphors-in-glass (PiG), which serves as a potential bi-replacement of both phosphors and organic encapsulants in high-power white light-emitting diodes (WLEDs), has captured much attention due to its high thermal stability and excellent luminescent properties. However, due to the high temperature-sensitivity and the chemical reactions between phosphors with glass matrix, a variety of phosphors, especially red phosphors could be hardly dispersed into the glass without thermal quenching and decomposition, which greatly limits the improvement of color rendering index and chromaticity tunability of the WLEDs. In this study, adopting the mesoporous silica (FDU-12) and commercial phosphors as raw materials, the phosphors-in-silica-glasses (PiSGs) embedded with red phosphor CaAlSiN3:Eu2+ and yellow phosphor YAG:Ce3+ have been successfully prepared at low sintering temperature (950 ?C) and short preparation time (10 min) using spark plasma sintering. Owing to the well preservation of the originally emissive properties of the embedded phosphors, the warm WLEDs with tunable chromaticity and exhibited a superior performance with LE of 133 lm/W, CCT of 3970 K and CRI of 81 were fabricated by encapsulating the as-prepared PiSGs on the blue chips. Moreover, the PiSG composite exhibits a high thermal conductivity up to 1.6 W/m·K.
关键词： white light-emitting diodes,phosphor in silica glass,tunable chromaticity,mesoporous silica
更新于2025-09-23 15:21:01
-
Synthesis of “lotus root”-like mesoporous titanium dioxide and its effects on UV response to aconitine release
摘要： Mesoporous titanium dioxide with a “lotus root”-like structure was synthesized for the first time using an improved template-free method. The structure has a BET (Brunauer Emmett Teller) surface area of 688.11 m2/g, a pore volume of 0.743 cm3/g, and a pore size of 3.59 nm. Aconitine, a botanical insecticide, could be loaded onto the mesoporous titanium dioxide via simply soaking the structure and had a maximum loading of 17.6 %. UV spectroscopy was utilized to explore the drug release behaviors, and the results showed that aconitine-loaded mesoporous titanium dioxide particles UV irradiated could successfully release aconitine with a release rate of 46.24%, which was significantly higher than the samples lacking UV irradiation (36.80%). Meanwhile, the release rate of aconitine (48.94 %) for pH 5.5 was significantly higher than that for pH 7.0 (42.09 %). The results of microcalorimetry revealed that both the enthalpy change (?H) and entropy change (?S) were negative (?H < 0, ?S < 0) for the whole process of aconitine loading onto the “lotus root”-like mesoporous titanium dioxide support. Hydrogen bonding was the driving force for drug loading, and this was also verified using Monte Carlo simulations. These results show that the “lotus root”-like mesoporous titanium dioxide material has some potential applications such as the storage and use of plant pesticides.
关键词： “Lotus root”-like mesoporous titanium dioxide,Monte Carlo simulations,hydrogen bonding,UV-responsed drug release
更新于2025-09-23 15:21:01
-
Mesoporous multi-silica layer-coated Y2O3:Eu core-shell nanoparticles: Synthesis, luminescent properties and cytotoxicity evaluation
摘要： Mesoporous multi-layered silica-coated luminescent Y2O3:Eu nanoparticles (NPs) were prepared by a urea-based decomposition process, and their surfaces were gradually modified with nanoporous and mesoporous silica layers using modified sol-gel methods. The synthesized luminescent core-shell NPs were characterized thoroughly to investigate their structural, morphological, thermal, optical, photo luminescent properties and their surface chemistry. The morphology of the core NPs were nearly spherical in shape and were nano-sized grains. The observed luminescent efficiency of the mesoporous multi-layered silica-coated luminescent core NPs was gradually reduced because of bond formation between the Y2O3:Eu core and the amorphous silica shell via YeOeSieOH bridges on the surface of the NPs; the bonds suppressed the non-radiative transition pathways. Biocompatibility tests on human breast cancer cells using the 3?(4,5?Dimethylthiazol?2?yl)?2,5?diphenyltetrazolium bromide and lactate dehydrogenase assays indicated that the core-shell NPs were non-toxic even at high concentrations. The mesoporous SiO2 layer played a key role in perfecting the solubility, biocompatibility, and non-toxicity of the NPs. The zeta potential, surface chemistry (Fourier transform infrared spectroscopy), and optical absorption spectral analyses revealed the high hydrophilicity of the as-prepared core-shell NPs because of the active surface-functionalized silanol (SieOH) groups, which could potentially offer many exciting opportunities in photonic-based biomedical applications.
关键词： Cytotoxicity,Mesoporous silica shell,Photoluminescence,Yttrium oxide,Raman spectra,Biocompatibility
更新于2025-09-23 15:21:01