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- 实验方案
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High Power Laser‐Driven Ce <sup>3+</sup> ‐Doped Yttrium Aluminum Garnet Phosphor Incorporated Sapphire Disc for Outstanding White Light Conversion Efficiency
摘要： A facile synthesis method for the development of Y3 (cid:2) xAl5O12:xCe3t (0.03–0.24) yellow phosphor via an auto-combustion method and fabrication of phosphor-incorporated sapphire disc (PISD) of various dimensions is reported. The photoluminescence (PL) intensity for the optimized concentration of Ce3t-doped yttrium aluminum garnet (YAG) phosphor is recorded at 550 nm wavelength under the excitation wavelength of 445 nm from a high power blue laser diode. The developed PISD exhibits high stability and luminescence. The blue laser diode is a promising candidate to revolutionize the luminous intensity of the white light by several orders of magnitude as compared with the existing blue light-emitting diodes. This emerging technology has an extremely bright future with endless uses of tunable power of the laser that controls the intensity of the emitted white light. Hence, this new approach provides a paradigm shift to produce highly ef?cient white light based on PISD integrated with blue laser diode as compared with the conventional technology. Moreover, such con?gurations allow more styling and packaging ?exibility that reduces the overall size of the fabricated unit and makes it favorable for various lighting applications.
关键词： blue laser diodes,photoluminescence,optical geometry,white light conversion,yellow phosphor
更新于2025-11-21 11:18:25
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White light emitting thermally stable bismuth phosphate phosphor Ca <sub/>3</sub> Bi( <scp>PO</scp><sub/>4</sub> ) <sub/>3</sub> :Dy <sup>3+</sup> for solid state lighting applications
摘要： White light emitting dysprosium doped Ca3Bi(PO4)3 phosphor was successfully synthesized via co-precipitation method for the first time and the structural, vibrational, morphological and luminescent properties have been investigated for solid state lighting applications. The X-ray diffraction (XRD) and structural refinement studies reveal that the synthesized phosphors consist of single phase with cubic structure. The field emission scanning electron microscopy (FE-SEM) images reveal that the as-synthesized phosphor has micron size with an irregular shape. Under near ultraviolet (n-UV) and blue excitation, the phosphor exhibits white light emission via a combination of blue (~451 nm) and yellow (~575 nm) emission bands. The optimized concentration of Dy3+ ions is 6.0 mol % after which the concertation quenching takes place. The process of energy transfer between Dy3+ ions is due to dipole-dipole interaction, which was confirmed by applying Dexter and Reisfeld’s Energy Transfer (ET) formula. The CIE chromaticity coordinates for the optimized phosphor were (0.329, 0.377), which lie in the white light region. The emission intensity remains to 83.41% at 373 K to that of at room temperature, which indicates good thermal stability. The above mentioned results demonstrate that Ca3Bi(PO4)3 is a potential phosphor for solid state lighting applications.
关键词： White LEDs,Structural and luminescent properties,White light emission,Phosphor,Thermally stable
更新于2025-11-21 11:18:25
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A novel near-infrared light responsive 4D printed nanoarchitecture with dynamically and remotely controllable transformation
摘要： Four-dimensional (4D) printing is an emerging and highly innovative additive manufacturing process by which to fabricate pre-designed, self-assembly structures with the ability to transform over time. However, one of the critical challenges of 4D printing is the lack of advanced 4D printing systems that not only meet all the essential requirements of shape change but also possess smart, dynamic capabilities to spatiotemporally and instantly control the shape-transformation process. Here, we present a facile 4D printing platform which incorporates nanomaterials into the conventional stimuli-responsive polymer, allowing the 4D printed object to achieve a dynamic and remote controlled, on-time and position shape transformation. A proof-of-concept 4D printed brain model was created using near-infrared light (NIR) responsive nanocomposite to evaluate the capacity for controllable 4D transformation, and the feasibility of photothermal stimulation for modulating neural stem cell behaviors. This novel 4D printing strategy can not only be used to create dynamic 3D patterned biological structures that can spatiotemporally control their shapes or behaviors of transformation under a human benign stimulus (NIR), but can also provide a potential method for building complex self-morphing objects for widespread applications.
关键词： brain,4D printing,dynamically and remotely controllable,neural stem cell,near-infrared light responsive,graphene
更新于2025-11-21 11:08:12
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A Light-Driven Micromotor with Complex Motion Behaviors for Controlled Release
摘要： Micromotor that exhibits various movement behaviors has attracted more attention in recent years. However, most researchers focus on its motion behavior and few have studied the fluid flow surrounding it. In this work, a novel micromotor with both controlled motion behavior and surrounding fluid flow, which is driven by near-infrared (NIR) light based on the unique Marangoni effect caused by the light irradiation of its constituent, i.e., polypyrrole (PPy), is reported. Interestingly, these motion behaviors and the surrounding fluid flow can be easily switched by adjusting the incident angle of the NIR laser. This unique property may have potentials in different fields. Among others, its application in remotely controlled targeted delivery and release is demonstrated.
关键词： micromotors,cargo release,light-driven,polypyrrole
更新于2025-11-21 11:03:13
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Reusability and photocatalytic activity of bismuth-TiO2 nanocomposites for industrial wastewater treatment
摘要： In this study, bismuth-TiO2 nanotube (Bi-TNT) composites were used for the treatment of industrial wastewater. Bi-TNT were synthesized using two- and one-step anodization methods. The obtained composites were analyzed using X-ray diffraction, field emission scanning electron microscopy, UV–visible diffuse reflectance spectroscopy, Energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. For the two-step Bi-TNT composites, we investigated the effect of different Bi deposition times, Bi concentrations, and Bi deposition voltages on photodegradation efficiency. For the one-step Bi-TNT composites, we investigated the effect of different anodization voltages, anodization times, and Bi concentrations. Initially, the optimal synthesis conditions for two- and one-step Bi-TNT catalysts were identified and then these optimized conditions were used for industrial wastewater treatment that was collected from Banwol Sihwa Industrial Complex Republic of Korea. The Bi-TNT two- and one-step composites showed 2.0 and 2.5 times higher photocatalytic activity, respectively, for industrial wastewater treatment than that of TNT in visible-light. Recycling of Bi-TNT composites showed that the one-step composite method was more efficient and stable than the two-step method because Bi coupling and nanotube formation simultaneously occurred.
关键词： Recycling,Two- and one-step methods,Visible-light,Pollutant degradation,Bi-TiO2 composite
更新于2025-11-21 11:01:37
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Enhanced Charge Separation in g-C3N4 – BiOI Heterostructures for Visible Light Driven Photoelectrochemical Water Splitting
摘要： Heterojunctions of the low bandgap semiconductor bismuth oxyiodide (BiOI) with bulk multilayered graphitic carbon nitride (g-C3N4) and few layered graphitic carbon nitride sheets (g-C3N4-S) are synthesized and investigated as an active photoanode material for sunlight driven water splitting. HR-TEM and elemental mapping reveals formation of a unique heterostructure between BiOI platelets and the carbon nitride (g-C3N4 and g-C3N4-S) network that consisted of dendritic BiOI nanoplates surrounded by g-C3N4 sheets. The presence of BiOI in g-C3N4-S/BiOI and g-C3N4-S/BiOI nanocomposites extends the visible light absorption profile from 500 nm up to 650 nm. Due to excellent charge separation in g-C3N4/BiOI and g-C3N4-S/BiOI, evident from quenching of the carbon nitride photoluminescence (PL) and a decrease in the PL lifetime, a significant increase in photoelectrochemical performance is observed for both types of g-C3N4-BiOI heterojunctions. In comparison to heterojunctions of bulk g-C3N4 with BiOI, the nancomposite consisting of few layered sheets of g-C3N4 and BiOI exhibits higher photocurrent density due to lower recombination in few layered sheets. A synergistic trap passivation and charge separation is found to occur in the g-C3N4-S/BiOI nanocomposite heterostructure which results in a higher photocurrent and a lower charge transfer resistance.
关键词： visible light driven photocatalysis,earth abundant semiconductor heterostructures,Graphenic semiconductors,photoelectrochemistry
更新于2025-11-21 11:01:37
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Dual Management of Electrons and Photons to Get High-Performance Light Emitting Devices Based on Si Nanowires and Si Quantum Dots with Al <sub/>2</sub> O <sub/>3</sub> -Ag Hybrid Nanostructures
摘要： Silicon quantum dot (Si QD)-based light emitting devices are fabricated on Si nanowire (Si NW) arrays. Through inserting Al2O3-Ag hybrid nanostructures (Al2O3-Ag HNs) between Si NWs and Si QDs, both photoluminescence (PL) and electroluminescence (EL) are remarkably enhanced compared to the control sample. The PL enhancement can be mainly attributed to passivation effect of Al2O3 to p-type Si NWs and enlarged absorption cross-section due to the local surface plasmon resonance effect of Ag nanoparticles. The EL intensity is enhanced by 14.9-fold at the same injection current under a lower applied voltage, which may result from the high injection efficiency of electrons and the promoted waveguide effect of nanowire structures with Al2O3-Ag HNs. It is demonstrated that light emitting device performances can be well improved by careful management of both electrons and photons via controlling the interface conditions of Si NWs/Si QDs.
关键词： hybrid nanostructures,silicon nanowires,light emitting devices,silicon quantum dots
更新于2025-11-21 11:01:37
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Low Power Consumption Red Light-Emitting Diodes Based on Inorganic Perovskite Quantum Dots under an Alternating Current Driving Mode
摘要： Inorganic perovskites have emerged as a promising candidate for light-emitting devices due to their high stability and tunable band gap. However, the power consumption and brightness have always been an issue for perovskite light-emitting diodes (PeLEDs). Here, we improved the luminescence intensity and decreased the current density of the PeLEDs based on CsPbI3 quantum dots (QDs) and p-type Si substrate through an alternating current (AC) driving mode. For the different driving voltage modes (under a sine pulsed bias or square pulsed bias), a frequency-dependent electroluminescent (EL) behavior was observed. The devices under a square pulsed bias present a stronger EL intensity under the same voltage due to less thermal degradation at the interface. The red PeLEDs under a square pulsed bias driving demonstrate that the EL intensity drop-off phenomenon was further improved, and the integrated EL intensity shows the almost linear increase with the increasing driving voltage above 8.5 V. Additionally, compared to the direct current (DC) driving mode, the red PeLEDs under the AC condition exhibit higher operating stability, which is mainly due to the reducing accumulated charges in the devices. Our work provides an effective approach for obtaining strong brightness, low power consumption, and high stability light-emitting devices, which will exert a profound in?uence on coupling LEDs with household power supplies directly.
关键词： low power consumption,perovskite quantum dots,silicon,light emitting diodes,alternating current driving
更新于2025-11-21 11:01:37
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Coral-Like Perovskite Nanostructures for Enhanced Light-Harvesting and Accelerated Charge Extraction in Perovskite Solar Cells
摘要： A novel coral-like perovskite nanostructured layer was grown on a compact perovskite foundation layer by the facile surface modification with dimethylformamide/isopropanol (DMF/IPA) as co-solvent. Surface morphological characterizations with SEM and XRD analyses revealed a growing mechanism of the new morphology, which was composed of the perovskite decomposition and recrystallization, excessive-PbI2 extraction, and sequential formation of coral-like nanostructured perovskite layer. The coral-like perovskite nanostructures resulted in significant light scattering, enhancing the light harvesting efficiency, and thus augmenting the photocurrent density. Moreover, the geometric configuration of the perovksite solar cells was changed from planar to bulk heterojunction, which results in the acceleration of charge separation and extraction due to the high surface area at the interface between the obtained perovskite and hole-transport layers. The optimal perovskite solar cell exhibited an impressive power conversion efficiency (PCE) of 19.47%, as compared to that of the pristine cell (17.19%).
关键词： solar cells,Bulk heterojunction,light-harvesting,coral-like nanostructures,surface modification,perovskite
更新于2025-11-21 11:01:37
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Superior light harnessing and charge injection kinetics utilizing mirror-like nano cuboidal ceria coupled with reduced graphene oxide in zinc oxide nanoparticle based photovoltaics
摘要： Efficiency in nanoparticle based photovoltaics is limited by optical transparency, light absorption as well as detrimental back transfer of electron at the hetero-interfaces. Three dimensional (3D) micro/nanostructures with excellent light scattering properties play pivotal role in light harvesting efficiency in DSSCs. Present study deals with the design and development of ternary hybrid photoanode utilizing high quality mirror like nano-cuboidal ceria (CeO2 NC) and 2D- reduced graphene oxide (RGO) sheets in conjunction with ZnO nanoparticle. A ～6% power conversion efficiency has been achieved for photoanode with optimized CeO2 NC loaded with 1 wt% RGO into ZnO NP. CeO2 NC owing to its size and high quality mirror like facets provides a better light harvesting by multiple interactions of incident photon with the absorber as revealed by UV–Vis diffused reflectance and IPCE analysis. 2D- RGO is proposed to act as an electron sink and provides faster electron transport pathway. Inclusion of 2D- RGO sheets yields a better charge injection kinetics (keinj ～ 2.3 × 108 s?1 for ternary, 1.1 × 108 s?1 for reference device) and collection at FTO as well as elevated recombination resistance (Rrec) and photo-induced electron life time (τe), unveiled by Electrochemical Impedance Spectroscopic (EIS) analysis corroborates a reduced reverse tunneling of photo-injected electron at ZnO/sensitizer/redox couple interface.
关键词： Diffusion,Mirror-like,Light scattering material,Reduced graphene oxide,Electrochemical impedance spectroscopy,Nano cuboidal
更新于2025-11-21 11:01:37