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1.
CeO2 and Fe2O3 co-modified titanate nanosheet (Fe2O3/CeO2@TNS) was prepared by one-pot hydrothermal method; the photocatalyst exhibited large surface area with CeO2 and Fe2O3 particles well dispersed on the surface. The results of XRD, BET, and Raman proved that the CeO2 and Fe2O3 introduced in the TNS influenced its structure evolution from 3D to 2D. The modification resulted in a shift of the absorption edge toward a longer wavelength and the band gap reduced to 2.87 eV. The three-component systems performed excellent photocatalytic activity and cycle stability on phenol and methyl blue (MB) solution under sunlight; nearly total phenol and MB were degraded in dozens of minutes. And the reaction rate constant (K) of Fe2O3/CeO2@TNS on phenol degradation was 1.77, 3.25, 4.88, and 13-fold of Fe2O3@TNS, CeO2@TNS, bare TNS, and P25, respectively. The enhanced photocatalytic activity could be ascribed to the efficient separation of photogenerated pairs through the formation of tandem n-n-n heterojunction among the three-component systems. This work will be useful for the design of other tandem n-n-n heterojunction photocatalytic systems for application in energy conversion and environmental remediation.
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2.
In this paper, an efficient strategy for the synthesis of graphene nanobelt-titanium dioxide/graphitic carbon nitride (graphene-TiO2/g-C3N4) heterostructure photocatalyst was applied to fabricate a kind of visible-light-driven photocatalyst. The heterostructure shows higher absorption edge towards harvesting more solar energy compared with pure TiO2 and pure g-C3N4 respectively. Furthermore, the as-prepared graphene-TiO2/g-C3N4 heterostructure can show enhanced photocatalytic activity under visible-light irradiation. These outstanding performances of photocatalytic activities for graphene-TiO2/g-C3N4 composites can be attributed to the heterojunction interfaces which can separate the electron-hole pairs and impede the recombination of electrons and holes more efficiently. This study conclusively demonstrates a facile and environmentally friendly new strategy to design highly efficient graphene-TiO2/g-C3N4 heterostructure photocatalytic materials for potential applications under visible-light irradiation.
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3.
Rare-earth-based infinite coordination polymer (RE-ICP) spheres with diameters ranging from 50 nm to 2 μm have been prepared using meso-2,3-dimercaptosuccinic acid (DMSA) as ligand under hydrothermal conditions. RE2O2SO4 microspheres with similar morphology were obtained by calcining the corresponding RE-ICP spheres. However, as for Ce-ICP and Sc-ICP, CeO2 and Sc2O3 were obtained. The products were characterized using X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, infrared spectroscopy, laser Raman spectrometry, and energy-dispersive X-ray spectrum. Elemental analysis and inductive coupled plasma atomic emission spectrometer were adopted to study the composition of the Eu-ICP. To explore their potential applications, several samples of the products were selected and their properties were investigated. The Eu-ICP and Eu2O2SO4 microspheres give strong red emissions when excited with a 394-nm ultraviolet light. Furthermore, the Eu-ICP displays a high selectivity for Fe(III). The obtained CeO2 has a strong absorption in the UV region and the Gd2O2SO4 microspheres show paramagnetic behavior.
Graphical abstract A series of RE2O2SO4 microspheres were prepared using a coordination polymer precursor method.
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4.
Minimizing of the boundary friction coefficient is critical for engine efficiency improvement. It is known that the tribological behavior has a major role in controlling the performance of automotive engines in terms of the fuel consumption. The purpose of this research is an experimental study to minimize the boundary friction coefficient via nano-lubricant additives. The tribological characteristics of Al2O3 and TiO2 nano-lubricants were evaluated under reciprocating test conditions to simulate a piston ring/cylinder liner interface in automotive engines. The nanoparticles were suspended in a commercially available lubricant in a concentration of 0.25 wt.% to formulate the nano-lubricants. The Al2O3 and TiO2 nanoparticles had sizes of 8–12 and 10 nm, respectively. The experimental results have shown that the boundary friction coefficient reduced by 35–51% near the top and bottom dead center of the stroke (TDC and BDC) for the Al2O3 and TiO2 nano-lubricants, respectively. The anti-wear mechanism was generated via the formation of protective films on the worn surfaces of the ring and liner. These results will be a promising approach for improving fuel economy in automotive.
Graphical Abstract Minimizing of the boundary friction coefficient in automotive engines using Al2O3 and TiO2 nanoparticles
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5.
One-dimensional Ce3+-doped Li4Ti5O12 (Li4Ti5?x Ce x O12, x?=?0, 0.01, 0.02, and 0.05) sub-microbelts with the width of approximately 500 nm and thickness of about 200 nm have been synthesized via the facile electrospinning method. The structure and morphology of the as-prepared samples are characterized by XRD, TEM, SEM, BET, HRTEM, XPS, and AFM. Importantly, one-dimensional Li4Ti5O12 sub-microbelts can be well preserved with the introduction of Ce3+ ions, while CeO2 impurity is obtained when x is greater than or equal to 0.02. The comparative experiments prove that Ce3+-doped Li4Ti5O12 electrodes exhibit the brilliant electrochemical performance than undoped counterpart. Particularly, the reversible capacity of Li4Ti4.98Ce0.02O12 electrode reaches up to 139.9 mAh g?1 and still maintains at 132.6 mAh g?1 even after 100 cycles under the current rate of 4 C. The superior lithium storage properties of Li4Ti4.98Ce0.02O12 electrode could be attributed to their intrinsic structure advantage as well as enhanced overall conductivity.
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6.
This paper reported a one-step synthesis of Ag2S/Ag@MoS2 nanocomposites and its applications in the surface-enhanced Raman scattering (SERS) detection and photocatalytic degradation of organic pollutants. The nanocomposites were well characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), cyclic voltammograms (CV), the Brunauer-Emmett-Teller (BET), and Fourier transforms infrared spectra (FTIR). The AgNPs were uniformly dispersed on the MoS2 nanosheets and the particle size of the AgNPs was about 10–30 nm. These Ag2S/Ag@MoS2 nanocomposites offered sensitive SERS signals for the detection of R6G with the limit of detections as low as 10?10 M. The photocatalytic activity of the composite catalyst was studied by the degradation of methylene blue (MB) dye under light illumination. The apparent rate constant of MB degradation for the obtained catalyst could reach 6.6?×?10?2 min?1, indicating that the novel Ag2S/Ag@MoS2 nanocomposites can be explored for organic pollutant’s detection and degradation.
Graphical abstract One-step synthesis of Ag2S/Ag@MoS2 nanocomposites for SERS and photocatalytic applications
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7.
Metal nanoparticles have been combined with magnet metal–organic frameworks (MOFs) to afford new materials that demonstrate an efficient catalytic degradation, high stability, and excellent reusability in areas of catalysis because of their exceptionally high surface areas and structural diversity. Magnetic M x O y @N-C (M = Fe, Co, Mn) nanocrystals were formed on nitrogen-doped carbon surface by using 8-hydroxyquinoline as a C/N precursor. The Co@N-C, MnO@N-C, and Fe/Fe2O3@N-C catalysts were characterized by X-ray diffraction (XRD), Raman, scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), N2 adsorption/desorption, and X-ray photoelectron spectroscopy (XPS). The catalytic performances of catalysts were thoroughly investigated in the oxidation of aniline solution based on sulfate radicals (SO4 ?.) toward Fenton-like reaction. Magnetic M x O y @N-C exhibits an unexpectedly high catalytic activity in the degradation of aniline in water. A high magnetic M x O y @N-C catalytic activity was observed after the evaluation by aniline degradation in water. Aniline degradation was found to follow the first-order kinetics, and as a result, various metals significantly affected the structures and performances of the catalysts, and their catalytic activity followed the order of Co > Mn > Fe. The nanoparticles displayed good magnetic separation under the magnetic field.
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8.
Carbon-coated ZnFe2O4 spheres with sizes of ~110–180 nm anchored on graphene nanosheets (ZF@C/G) are successfully prepared and applied as anode materials for lithium ion batteries (LIBs). The obtained ZF@C/G presents an initial discharge capacity of 1235 mAh g?1 and maintains a reversible capacity of 775 mAh g?1 after 150 cycles at a current density of 500 mA g?1. After being tested at 2 A g?1 for 700 cycles, the capacity still retains 617 mAh g?1. The enhanced electrochemical performances can be attributed to the synergetic role of graphene and uniform carbon coating (~3–6 nm), which can inhibit the volume expansion, prevent the pulverization/aggregation upon prolonged cycling, and facilitate the electron transfer between carbon-coated ZnFe2O4 spheres. The electrochemical results suggest that the synthesized ZF@C/G nanostructures are promising electrode materials for high-performance lithium ion batteries.
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9.
The Br-doped hollow TiO2 photocatalysts were prepared by a simple hydrothermal process on the carbon sphere template following with calcination at 400 °C. The structure and properties of photocatalysts were characterized by X-ray diffraction, Raman spectrum, scanning electron microscope, transmission electron microscopy, N2 desorption–adsorption, UV–Vis spectroscopy, and X-ray photoelectron spectroscopy. The TiO2 hollow spheres are in diameter of 500 nm with shell thickness of 50 nm. The shell is composed of small anatase nanoparticles with size of about 10 nm. The TiO2 hollow spheres exhibit high crystalline and high surface area of 89.208 m2/g. With increasing content of Br doping, the band gap of TiO2 hollow spheres decreased from 2.85 to 1.75 eV. The formation of impurity band in the band gap would narrow the band gap and result in the red shift of absorption edge from 395 to 517 nm, which further enhances the photocatalytic activity. The appropriate Br doping improves the photocatlytic activity significantly. The TiO2 hollow spheres with 1.55% Br doping (0.5Br-TiO2) exhibit the highest photocatalytic activity under full light. More than 98% of RhB, MO, and MB can be photodegraded using 0.5Br-TiO2 with concentration of 10 mg/L in 40, 30, and 30 min, respectively. The degradation rate of Br-doped photocatalysts was 40% faster than undoped ones.
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10.
Spinel ferrites can be used in magnetic targeting and microwave heating and can therefore be used for targeted and controllable drug delivery. We used the cetyltrimethylammonium bromide-assisted solvothermal method to synthesize a series of spinel ferrites (MxFe3-xO4, M=Mg, Mn, Fe, Co, Ni, Cu, Zn) with a mesoporous or hollow-mesoporous structure suitable for direct drug loading and the particle diameters ranging from 200 to 350 nm. We investigated the effects of M2+ cation on the morphology and properties of these products by analyzing their transmission electron microscopy images, mesoporous properties, magnetic properties, and microwave responses. We chose hollow-mesoporous MxFe3-xO4 (M=Fe, Co, Zn) nanoparticles, which had better overall properties, for the drug VP16 (etoposide) loading and microwave-controlled release. The CoxFe3-xO4 and Fe3O4 particles trapped 61.5 and 64.8%, respectively, of the VP16, which were higher than that (60.4%) of ZnxFe3-xO4. Controllable drug release by these simple magnetic nanocarriers can be achieved by microwave irradiation, and VP16-loaded CoxFe3-xO4 released the most VP16 molecules (more than 50% after 1 h and 69.1% after 6 h) under microwave irradiation. Our results confirm the favorable drug loading and microwave-controlled delivery by these ferrites, and lay a theoretical foundation to promote clinical application of the targeted controllable drug delivery system.
Graphical abstract In the present study, we prepared mesoporous or hollow-mesoporous spinel ferrites (MxFe3-xO4, M=Mg, Mn, Fe, Co, Ni, Cu, Zn) by CTAB-assisted solvothermal method and solved the problem of Cu and Ni impurities in CuxFe3-xO4 and NixFe3-xO4 products by means of magnetic separation and additional redox reactions, respectively. We investigated the effects of the M2+ cation on the morphology, mesoporous properties, magnetic properties, and microwave responses of these ferrites. Then, the drug loading and microwave-controlled drug release of hollow-mesoporous MxFe3-xO4 (M?=?Fe, Co, Zn) nanoparticles with better overall properties were also studied. CoxFe3-xO4 has the best overall performances for microwave-controlled drug release.
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11.
Solution combustion synthesis (SCS) is an effective and rapid method for synthesizing nanocrystalline materials. However, the control over size, morphology, and microstructure are rather limited in SCS. Here, we develop a novel ultrasonic-assisted solution combustion route to synthesize the porous and nano-sized Na3V2(PO4)3/C composites, and reveal the effects of ultrasound on the structural evolution of NVP/C. Due to the cavitation effects generated from ultrasonic irradiation, the ultrasonic-assisted SCS can produce honeycomb precursor, which can be further transformed into porous Na3V2(PO4)3/C with reticular and hollow structures after thermal treatment. When used as cathode material for Na-ion batteries, the porous Na3V2(PO4)3/C delivers an initial discharge capacity of 118 mAh g?1 at 0.1 C and an initial coulombic efficiency of 85%. It can retain 93.8% of the initial capacity after 120 cycles at 0.2 C. The results demonstrate that ultrasonic-assisted SCS can be a new strategy to design crystalline nanomaterials with tunable microstructures.
Graphical abstract Porous and nano-sized Na3V2(PO4)3/C composites with reticular and hollow structures are synthesized by an ultrasonic-assisted solution combustion route due to the cavitation effects, and exhibit excellent electrochemical performance as cathode in sodium ion battery.
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12.
A facile and efficient one-pot method for the synthesis of well-dispersed hollow CuFe2O4 nanoparticles (H-CuFe2O4 NPs) in the presence of cellulose nanocrystals (CNC) as the support was described. Based on the one-pot solvothermal condition control, magnetic H-CuFe2O4 NPs were in-situ grown on the CNC surface uniformly. TEM images indicated good dispersity of H-CuFe2O4 NPs with uniform size of 300 nm. The catalytic activity of H-CuFe2O4/CNC was tested in the catalytic reduction of 4-nitrophenol (4-NP) in aqueous solution. Compared with most CNC-based ferrite catalysts, H-CuFe2O4/CNC catalyst exhibited an excellent catalytic activity toward the reduction of 4-NP. The catalytic performance of H-CuFe2O4/CNC catalyst was remarkably enhanced with the rate constant of 3.24 s?1 g?1, which was higher than H-CuFe2O4 NPs (0.50 s?1 g?1). The high catalytic activity was attributed to the introduction of CNC and the special hollow mesostructure of H-CuFe2O4 NPs. In addition, the H-CuFe2O4/CNC catalyst promised good conversion efficiency without significant decrease even after 10 cycles, confirming relatively high stability. Because of its environmental sustainability and magnetic separability, H-CuFe2O4/CNC catalyst was shown to indicate that the ferrite nanoparticles supported on CNC were acted as a promising catalyst and exhibited potential applications in numerous ferrite based catalytic reactions.
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13.
In this investigation, phosphotungstic acid (H3PW12O40) was successfully self-assembly implanted into the interspace of K4Nb6O17 nanosheet via an impregnation method to form an adsorption-photocatalytic composite, in which n-type semiconductor K4Nb6O17 was selected as photo-electron emitter and H3PW12O40 was particularly used as an electronic transmitter. By characterizing with X-ray diffraction (XRD), transmission (TEM), scan electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and FT-IR spectrum (FT-IR), it confirmed that H3PW12O40 (HPW) was converted to the insoluble tiny particles of K3PW12O40 (KPW) with the remained primary Keggin group via an ion-exchanged H+ of HPW with K+ in K4Nb6O17 in the implanted process and was firmly bound to the surface of K4Nb6O17 to form well sandwich structure. UV-vis diffuse reflectance spectroscopy revealed that the band gap of K4Nb6O17-K3PW12O40 have a slight red shift compared with the single K4Nb6O17. Its adsorption-photocatalytic properties were evaluated with the removal of tetracycline as model reaction. Compared with pure K4Nb6O17, tetracycline removal rate can be significantly improved for the as-prepared sandwich. Importantly, the removal could still maintain 70% after five reuses in recycle tests at an acidic solution, inferring a good stability which was mainly ascribed to the formation of water-insoluble K3PW12O40. The separation and transfer process of photogenerated electrons were investigated by surface photovoltage spectroscopy (SPV). It proposed that the KPW anchored firmly on the interlayers of K4Nb6O17 through a O-K-O bridge plays a significantly role in promoting the separation of the photogenerated carriers and preventing the leakage and agglomeration of HPW. The present results showed that the strategy of the phosphotungstic acid binding in situ to K4Nb6O17 was favorable to promote the hetero-photocatalytic efficiency as well as reusability.
Graphical abstract Mechanism for tetracycline photodegradation over the K4Nb6O17-KPW photocatalytic system
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14.
In flame spray pyrolysis (FSP), the generation of uniform nanoparticles can be quite challenging due to difficulties in controlling droplet sizes during liquid spraying and uneven flame temperature. Here, we report a method to produce relatively uniform nanocrystals of a Tb3+ doped Y2O3 phosphor. In ethanol, metal nitrate precursors were simply mixed with organic surfactants to form a homogeneous solution which was then subjected to FSP. Depending on relative concentrations of the surfactant (oleic acid) to the metal precursors (yttrium and terbium nitrates), different sizes and morphologies of Y2O3:Tb3+ particles were obtained. By adjusting the surfactant concentration, Y2O3:Tb3+ crystals as small as 20~25 nm were acquired. X-ray diffraction and transmittance electron microscopy were used to prove that as-synthesized nanoparticles were highly crystalline due to the high temperature of FSP. X-ray photoelectron spectroscopy revealed that terbium dopants were well distributed throughout Y2O3 particles and a small portion of carbonate impurities were remained on the surface of particles, presumably originated from incomplete combustion of the organic surfactants. Photoluminescence (PL) spectra of Y2O3:Tb3+ nanocrystals exhibited a green light emission ensuring that the terbium doping was successfully occurred. However, when post-annealing was performed on the nanocrystals, their PL was dramatically enhanced indicating that quenching centers such as carbonate impurities and surface defects may have been removed by the annealing process. Owing to the continuous processability of FSP, this current method can be a practical way to produce nanoparticles in a large quantity. The obtained Y2O3:Tb3+ nanocrystals were used to fabricate a transparent film with poly-ethylene-co-vinyl acetate (poly-EVA) polymer, which was suitable for a spectral converting layer for a solar cell.
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15.
Perovskite solar cell is a kind of revolutionary investigation in the field of renewable energy which is capable of mitigates the deficiencies of silicon solar cell and its uprising efficiency can bring blessing to society. The presence of lead (Pb) in perovskite solar cell can make worst and negative impact on environment and is not desirable for our society. In this paper, general plans are anticipated by replacement of Pb with tin (Sn) in open atmosphere to fabricate the CH3NH3SnCl3 photovoltaic cells in chlorine (Cl)-rich environment. Excess uses of Cl has positive influences on morphological growth of the film and it also suppresses the oxidation tendency of tin (Sn) with existing oxygen in atmosphere and maintains same chemical atmosphere as bulk. Various characterization tools like X-ray diffraction, scanning electron microscope (SEM) have been used to study the effect of annealing temperature on crystal stricture, phase formation, impurities, and morphologies of the film. Finally, photovoltaic performance was reported using the solar simulator under 1.5 sun illumination.
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16.
Ternary copper indium sulfide (CIS) nanocrystals (NCs) have been synthesized by mixing of binary precursor [CuI(bdpa)2][CuICl2] (1) and/or [CuI(mdpa)2][CuICl2] (2) (where, mdpa and bdpa represent methyl and benzyl ester of 3,5-dimethyl pyrazole-1-dithioic acid, respectively) with InCl3 in a low-temperature solvothermal process. The +1 oxidation state of copper and the atomic ratio Cu to S (1:2) is atomically maintained in the pyrazole-based Cu(I)–S precursor to synthesize phase pure CuInS2. Coordinating solvents like ethylene diamine (EN) and ethylene glycol (EG) have been used in the synthesis without any surfactants. No use of external surfactants in the synthesis of CIS nanoparticles reveals that precursor acts as stabilizing agent. The synthesized nanocrystals were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and energy dispersive X-ray spectroscopy (EDX) studies. The optical property of the nanocrystals shows a pronounced quantum confinement effect in the particles with band gap energy ca. 1.5 eV. The formation mechanism of ternary CIS has been proposed. The pore size distributions of the particles show the average pore diameters 13.1 nm from 1 and 5.3 nm from 2. The calculated values of the specific surface area are 8.123 and 9.577 m2/g for 1 and 2, respectively. The excellent photocatalytic degradation of rose bengal (RB) and rhodamine B (RhB) was demonstrated by the porous CIS nanocrystals.
Graphical abstract Enhanced photocatalytic activity of ternary CuInS2 nanocrystals synthesized from the combination of a binary Cu(I)S precursor and InCl3. Gopinath Mondal, Ananyakumari Santra, Sumanta Jana, Nimai Chand Pramanik, Anup Mondal and Pulakesh Bera
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17.
Carbon-based nanoparticles (NPs) such as fullerenes and nanotubes have been extensively studied for drug delivery in recent years. The permeation process of fullerene and its derivative molecules through membrane is essential to the utilization of fullerene-based drug delivery system, but the mechanism and the dynamics of permeation through cell membrane are still unclear. In this study, coarse-grained molecular dynamics simulations were performed to investigate the permeation process of functionalized fullerene molecules (ca. 0.72 nm) through the membrane. Our results show that single functionalized fullerene molecule in such nanoscale could permeate the lipid membrane in micro-second time scale. Pristine C60 molecules prefer to aggregate into several small clusters while C60OH15 molecules could aggregate into one big cluster to permeate through the lipid membrane. After permeation of C60 or its derivatives into membrane, all C60 and C60OH15 molecules disaggregated and monodispersed in the lipid membrane.
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18.
Asymmetric capacitor based on TiO2 with the size range from 90 to 410 nm and mesoporous MnO2 (ca. 200–380 nm) electrodes has been successfully constructed and characterized in LiClO4 aqueous electrolyte. The samples of both metal oxides were fully characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD), transmission electron microscopy (TEM), energy-dispersive X-ray analysis (EDX), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), N2 adsorption-desorption, and so on. The electrochemical capacitive performances of both electrode materials were evaluated by cyclic voltammetry and galvanostatic charge-discharge in 1 mol/L LiClO4 with a working voltage of 2.0 V. The discharge profile of the asymmetric capacitor exhibited an excellent capacitive behavior and good cycling stability after 2000 cycles. Moreover, the TiO2//MnO2 asymmetric capacitor possesses both higher energy density and power density (7.7 Wh/kg, 762.5 W/kg) than that of Maxsorb//Maxsorb symmetrical capacitor (7.0 Wh/kg, 400.0 W/kg).
Graphical abstract A novel asymmetric capacitor based on TiO2 and mesoporous MnO2 electrodes has been successfully constructed and characterized in LiClO4 aqueous electrolyte.
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19.
Currently, all-inorganic cesium lead-halide perovskite nanocrystals have attracted enormous attentions owing to their excellent optical performances. While great efforts have been devoted to CsPbBr3 nanocrystals, the perovskite-related Cs4PbBr6 nanocrystals, which were newly reported, still remained poorly understood. Here, we reported a novel room-temperature reaction strategy to synthesize pure perovskite-related Cs4PbBr6 nanocrystals. Size of the products could be adjusted through altering the amount of ligands, simply. A mixture of two good solvents with different polarity was innovatively used as precursor solvent, being one key to the high-yield Cs4PbBr6 nanocrystals synthesis. Other two keys were Cs+ precursor concentration and surface ligands. Ingenious experiments were designed to reveal the underlying reaction mechanism. No excitonic emission was observed from the prepared Cs4PbBr6 nanocrystals in our work. We considered the green emission which was observed in other reports originated from the avoidless transformation of Cs4PbBr6 into CsPbBr3 nanocrystals. Indeed, the new-prepared Cs4PbBr6 nanocrystals could transform into CsPbBr3 nanosheets with surface ligands mediated. The new-transformed two-dimensional CsPbBr3 nanosheets could evolve into large-size nanosheets. The influences of surface ligand density on the fluorescent intensity and stability of transformed CsPbBr3 nanosheets were also explained. Notably, the photoluminescence quantum yield of the as-transformed CsPbBr3 nanosheets could reach as high as 61.6% in the form of thin film. The fast large-scale synthesis of Cs4PbBr6 nanocrystals and their ligand-mediated transformation into high-fluorescent CsPbBr3 nanosheets will be beneficial to the future optoelectronic applications. Our work provides new approaches to understand the structural evolution and light-emitting principle of perovskite nanocrystals.
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20.
This work reported a novel kind of CdTe quantum dot (QD) decorated mesoporous SiO2 (m-SiO2/QD) hybrid hollow nanoparticles for carrying photodynamic therapy (PDT) reagent. Both rod-like and spherical nanoparticles were prepared by using different shaped templates. Due to the porous shell and hollow interior, the hybrid m-SiO2/QD hollow nanorod with 360 nm long and 120 nm in diameter was selected for carrying zinc(II) phthalocyanine (ZnPc) photosensitizing molecules (61 mg/g) since the generated reactive 1O2 could be easily delivered out of the hollow particles through the porous shell (BET area 251 cm2/g). It was found that the m-SiO2/QD-ZnPc hollow nanorods exhibited a good PDT activity and showed effective photocytotoxicity for the cancer cells. Because of the porous nature, fluorescence characteristic, and excellent storage ability, the m-SiO2/QD hybrid hollow particles possessed broad potential in the fluorescent labeled PDT.
Graphic abstract m-SiO2/QD hybrid hollow particles with different morphologies could be successfully synthesized by using the templating method and they could be used as carriers for photodynamic therapy reagents.
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