The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
Jianfang Wang - One of the best experts on this subject based on the ideXlab platform.
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Aerosol-Spray metal phosphide microspheres with bifunctional electrocatalytic properties for water splitting
Journal of Materials Chemistry A, 2018Co-Authors: Henglei Jia, Ruibin Jiang, Qifeng Ruan, Jianfang WangAbstract:Transition metal phosphides have sparked considerable interest as electrocatalysts owing to their excellent catalytic activities towards water splitting. However, the development of a general strategy for the preparation of metal phosphides has remained challenging. In this work, we demonstrate a two-step, Aerosol Spray-based strategy for the synthesis of various mesoporous monometallic and multimetallic phosphide microspheres. Four monometallic (FeP, CoP, Ni2P, and Cu3P), one bimetallic (Co6Ni4P5) and one trimetallic (Co4Ni3Cu2P10) phosphide samples are successfully prepared, suggesting the generality of our method. In addition, the CoP sample is found to be an excellent material for the hydrogen evolution reaction over a wide pH range through the introduction of corrosion-resistant Cr2O3. On the other hand, its catalytic activity can be switched to the oxygen evolution reaction in combination with Fe2O3. The overpotential for the oxygen evolution reaction to generate a current density of 10 mA cm−2 is as low as 302 mV. This activity can be maintained for at least 50 h. More importantly, a two-electrode electrolyzer constructed from 10% Cr–CoP and 30% Fe–CoP samples delivers a current density of 100 mA cm−2 at a cell voltage of merely 1.67 V, showing the use of these cost-effective materials for bifunctional water splitting.
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Aerosol Spray diverse mesoporous metal oxides from metal nitrates
Scientific Reports, 2015Co-Authors: Long Kuai, Baoyou Geng, Junxin Wang, Tian Ming, Caihong Fang, Jianfang WangAbstract:Transition metal oxides are widely used in solar cells, batteries, transistors, memories, transparent conductive electrodes, photocatalysts, gas sensors, supercapacitors, and smart windows. In many of these applications, large surface areas and pore volumes can enhance molecular adsorption, facilitate ion transfer, and increase interfacial areas; the formation of complex oxides (mixed, doped, multimetallic oxides and oxide-based hybrids) can alter electronic band structures, modify/enhance charge carrier concentrations/separation, and introduce desired functionalities. A general synthetic approach to diverse mesoporous metal oxides is therefore very attractive. Here we describe a powerful Aerosol-Spray method for synthesizing various mesoporous metal oxides from low-cost nitrate salts. During Spray, thermal heating of precursor droplets drives solvent evaporation and induces surfactant-directed formation of mesostructures, nitrate decomposition and oxide cross-linking. Thirteen types of monometallic oxides and four groups of complex ones are successfully produced, with mesoporous iron oxide microspheres demonstrated for photocatalytic oxygen evolution and gas sensing with superior performances.
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ultrasonic Aerosol Spray assisted preparation of tio2 in2o3 composite for visible light driven photocatalysis
Journal of Catalysis, 2014Co-Authors: Tian Ming, Junxin Wang, Jianfang WangAbstract:A TiO2/In2O3 composite photocatalyst has been prepared by using a facile ultrasonic Aerosol Spray (UAS)-assisted method. Results from scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and N2 adsorption–desorption measurements reveal that the as-prepared TiO2/In2O3 composite exhibits a porous structure and spherical morphology. The diameter ranges from tens of nanometers to several micrometers. According to the UV–vis diffuse reflectance spectra, the TiO2/In2O3 composite shows good visible-light absorption ability. The photocatalytic activity of the samples was evaluated by the decomposition of organic dyes in aqueous solutions under visible-light irradiation. All the composite samples show excellent photocatalytic performance. The effect of In2O3 content on the photocatalytic activity was also investigated. The best photocatalytic activity results from the TiO2/In2O3 sample with Ti:In molar ratio of 100:1. The UAS-assisted method can also be applied for the preparation of other composite semiconductor materials. It provides a general approach for scaling up the production of photocatalysts for practical applications.
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Ultrasonic Aerosol Spray-assisted preparation of TiO2/In2O3 composite for visible-light-driven photocatalysis
Journal of Catalysis, 2014Co-Authors: Tian Ming, Junxin Wang, Jianfang WangAbstract:A TiO2/In2O3 composite photocatalyst has been prepared by using a facile ultrasonic Aerosol Spray (UAS)-assisted method. Results from scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and N2 adsorption–desorption measurements reveal that the as-prepared TiO2/In2O3 composite exhibits a porous structure and spherical morphology. The diameter ranges from tens of nanometers to several micrometers. According to the UV–vis diffuse reflectance spectra, the TiO2/In2O3 composite shows good visible-light absorption ability. The photocatalytic activity of the samples was evaluated by the decomposition of organic dyes in aqueous solutions under visible-light irradiation. All the composite samples show excellent photocatalytic performance. The effect of In2O3 content on the photocatalytic activity was also investigated. The best photocatalytic activity results from the TiO2/In2O3 sample with Ti:In molar ratio of 100:1. The UAS-assisted method can also be applied for the preparation of other composite semiconductor materials. It provides a general approach for scaling up the production of photocatalysts for practical applications.
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Multifunctional Mesostructured Silica Microspheres from an Ultrasonic Aerosol Spray
Advanced Functional Materials, 2008Co-Authors: Chia-kuang Tsung, Tian Ming, Zhenhua Sun, Qihui Shi, Galen D. Stucky, Jianfang WangAbstract:Multifunctional mesostructured silica microspheres are prepared using ultrasonic Aerosol Spray in conjunction with solvent evaporation-induced assembly. Rare earth ion-phenanthroline complexes, magnetite particles, photoacid generators, and pH-sensitive dyes are chosen as luminescent, magnetic, and photosensitive components. The incorporation of these functional components into mesostructured silica microspheres can be readily realized by dispersing them in the precursor solution of the Aerosol Spray process. Luminescent microspheres that can emit at multiple wavelengths when excited at a single wavelength are produced by the addition of multiple rare earth complexes into the precursor solution. The addition of magnetite particles leads to the production of magnetic luminescent microspheres. Photoacid generators and pH-sensitive dyes are further employed to produce magnetic photosensitive microspheres that can release acid and change color upon UV light illumination. Such multifunctional microspheres could have exciting potential for many optical and biotechnological applications, such as multiplexed labeling, diagnosis, simultaneous imaging and therapy, cell capture and separation, targeted delivery, and optical data storage.
Tian Ming - One of the best experts on this subject based on the ideXlab platform.
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Aerosol Spray diverse mesoporous metal oxides from metal nitrates
Scientific Reports, 2015Co-Authors: Long Kuai, Baoyou Geng, Junxin Wang, Tian Ming, Caihong Fang, Jianfang WangAbstract:Transition metal oxides are widely used in solar cells, batteries, transistors, memories, transparent conductive electrodes, photocatalysts, gas sensors, supercapacitors, and smart windows. In many of these applications, large surface areas and pore volumes can enhance molecular adsorption, facilitate ion transfer, and increase interfacial areas; the formation of complex oxides (mixed, doped, multimetallic oxides and oxide-based hybrids) can alter electronic band structures, modify/enhance charge carrier concentrations/separation, and introduce desired functionalities. A general synthetic approach to diverse mesoporous metal oxides is therefore very attractive. Here we describe a powerful Aerosol-Spray method for synthesizing various mesoporous metal oxides from low-cost nitrate salts. During Spray, thermal heating of precursor droplets drives solvent evaporation and induces surfactant-directed formation of mesostructures, nitrate decomposition and oxide cross-linking. Thirteen types of monometallic oxides and four groups of complex ones are successfully produced, with mesoporous iron oxide microspheres demonstrated for photocatalytic oxygen evolution and gas sensing with superior performances.
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ultrasonic Aerosol Spray assisted preparation of tio2 in2o3 composite for visible light driven photocatalysis
Journal of Catalysis, 2014Co-Authors: Tian Ming, Junxin Wang, Jianfang WangAbstract:A TiO2/In2O3 composite photocatalyst has been prepared by using a facile ultrasonic Aerosol Spray (UAS)-assisted method. Results from scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and N2 adsorption–desorption measurements reveal that the as-prepared TiO2/In2O3 composite exhibits a porous structure and spherical morphology. The diameter ranges from tens of nanometers to several micrometers. According to the UV–vis diffuse reflectance spectra, the TiO2/In2O3 composite shows good visible-light absorption ability. The photocatalytic activity of the samples was evaluated by the decomposition of organic dyes in aqueous solutions under visible-light irradiation. All the composite samples show excellent photocatalytic performance. The effect of In2O3 content on the photocatalytic activity was also investigated. The best photocatalytic activity results from the TiO2/In2O3 sample with Ti:In molar ratio of 100:1. The UAS-assisted method can also be applied for the preparation of other composite semiconductor materials. It provides a general approach for scaling up the production of photocatalysts for practical applications.
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Ultrasonic Aerosol Spray-assisted preparation of TiO2/In2O3 composite for visible-light-driven photocatalysis
Journal of Catalysis, 2014Co-Authors: Tian Ming, Junxin Wang, Jianfang WangAbstract:A TiO2/In2O3 composite photocatalyst has been prepared by using a facile ultrasonic Aerosol Spray (UAS)-assisted method. Results from scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and N2 adsorption–desorption measurements reveal that the as-prepared TiO2/In2O3 composite exhibits a porous structure and spherical morphology. The diameter ranges from tens of nanometers to several micrometers. According to the UV–vis diffuse reflectance spectra, the TiO2/In2O3 composite shows good visible-light absorption ability. The photocatalytic activity of the samples was evaluated by the decomposition of organic dyes in aqueous solutions under visible-light irradiation. All the composite samples show excellent photocatalytic performance. The effect of In2O3 content on the photocatalytic activity was also investigated. The best photocatalytic activity results from the TiO2/In2O3 sample with Ti:In molar ratio of 100:1. The UAS-assisted method can also be applied for the preparation of other composite semiconductor materials. It provides a general approach for scaling up the production of photocatalysts for practical applications.
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Multifunctional Mesostructured Silica Microspheres from an Ultrasonic Aerosol Spray
Advanced Functional Materials, 2008Co-Authors: Chia-kuang Tsung, Tian Ming, Zhenhua Sun, Qihui Shi, Galen D. Stucky, Jianfang WangAbstract:Multifunctional mesostructured silica microspheres are prepared using ultrasonic Aerosol Spray in conjunction with solvent evaporation-induced assembly. Rare earth ion-phenanthroline complexes, magnetite particles, photoacid generators, and pH-sensitive dyes are chosen as luminescent, magnetic, and photosensitive components. The incorporation of these functional components into mesostructured silica microspheres can be readily realized by dispersing them in the precursor solution of the Aerosol Spray process. Luminescent microspheres that can emit at multiple wavelengths when excited at a single wavelength are produced by the addition of multiple rare earth complexes into the precursor solution. The addition of magnetite particles leads to the production of magnetic luminescent microspheres. Photoacid generators and pH-sensitive dyes are further employed to produce magnetic photosensitive microspheres that can release acid and change color upon UV light illumination. Such multifunctional microspheres could have exciting potential for many optical and biotechnological applications, such as multiplexed labeling, diagnosis, simultaneous imaging and therapy, cell capture and separation, targeted delivery, and optical data storage.
George Kiriakidis - One of the best experts on this subject based on the ideXlab platform.
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Vanadium oxide nanostructured thin films prepared by Aerosol Spray Pyrolysis for gas sensing and thermochromic applications
Materials Science in Semiconductor Processing, 2019Co-Authors: S. Gavalas, George Kiriakidis, E. Gagaoudakis, D. Katerinopoulou, V. Petromichelaki, S. Wight, G. Wotring, E. Aperathitis, Vassilios BinasAbstract:Abstract Vanadium oxide (VxOy) nanostructured films were prepared by Aerosol Spray Pyrolysis technique with different concentrations of precursor solution (0.005 M, 0.01 M, 0.02 M), using ammonium metavanadate (NH4VO3) as precursor. The deposition was carried out onto glass substrates (Corning glass) at two different substrate temperatures (300 °C and 400 °C). Furthermore, oxalic acid was added to the precursor solution in order to grow the thermochromic VO2(M) monoclinic phase via reduction of the Vanadium oxides in which Vanadium is in a higher oxidizing state. All films were characterized by X-Ray Diffraction technique and UV/Vis/NIR spectroscopy to identify their structural and optical properties, respectively. V2O5 films were tested against ozone, having a sensitivity of 29% in ultra-low concentration of 5ppb ozone, at room temperature. Moreover, nanostructured VO2 films appeared to be thermochromic, having an IR-switching of about 5% at λ = 2500 nm, upon heating.
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A study on the sensing of NO2 and O2 utilizing ZnO films grown by Aerosol Spray pyrolysis
Materials Chemistry and Physics, 2015Co-Authors: G.h. Mhlongo, Ioannis Kortidis, David E. Motaung, Bonex W. Mwakikunga, Suprakas Sinha Ray, Ntombizodwa R. Mathe, Odireleng M. Ntwaeaborwa, H.c. Swart, George KiriakidisAbstract:Abstract The present paper addresses the preparation and characterization of ZnO nanostructured thin films obtained using Aerosol Spray pyrolysis method at different deposition periods. Aiming at understanding the chemical composition, structural and morphological properties of the samples, characterization was performed using X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), atomic force microscopy (AFM) and focused ion beam scanning electron microscopy (FIB-SEM), respectively. Defect structures were characterized by photoluminescence (PL), Raman, and electron paramagnetic resonance (EPR) techniques. The purity and crystallinity of the deposited films with increasing growth time were confirmed from XRD studies supported by Raman studies. AFM and SEM revealed morphology transition from uniform small particles to rod-like structures fused together growing perpendicular to the surface with prolonged deposition time. Optical absorption analyses revealed the decrease in the optical band-gap energy from 3.38 to 3.27 eV with prolonged growth time. The dominant emission at 2.80 eV (445 nm) in the PL spectra signifies the presence of Zni in the ZnO nanostructures which is shown to slightly decrease with an increase in growth time. EPR analyses revealed higher ferromagnetic (FM) signal for ZnO films grown for 20 min. Improved sensitivity to both NO2 and O2 was observed for ZnO nanostructured film grown for 20 min owing to higher Zni and VO as compared to its counterpart. Film grown for longer periods showed a decrease on the FM and sensitivity due to reduced Zni and VO defects induced by larger grain sizes.
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Orientation-dependent low field magnetic anomalies and room-temperature spintronic material – Mn doped ZnO films by Aerosol Spray pyrolysis
Journal of Alloys and Compounds, 2013Co-Authors: S.s. Nkosi, Ioannis Kortidis, David E. Motaung, Gerald F. Malgas, J. M. Keartland, Elias Sideras-haddad, Andrew Forbes, Bonex W. Mwakikunga, S. Sinha-ray, George KiriakidisAbstract:Abstract High quality un-doped and Mn-doped ZnO films deposited by a simple Aerosol Spray pyrolysis technique for 20 and 30 min were studied using electron paramagnetic resonance (EPR), X-ray diffraction (XRD) and atomic force microscopy (AFM) techniques. EPR analysis showed novel observation of low field microwave absorption (LFMA) on the manganese (Mn) doped zinc oxide (ZnO) films at various Mn concentrations. The results showed a peculiar behavior, reversal signal to that of LFMA. These findings also demonstrated that these films contain ferromagnetism at room temperature with possible applications in spintronics. Angular dependence measurements were found to induce magnetic transition from ferromagnetism to paramagnetism. Structural analysis showed that the undertaken materials are in wurtzite structures. The light absorption edge of Mn–ZnO films red shifted which enhanced the observed ferromagnetism. The direct modulation of the band gap caused by Mn–ZnO substitution is responsible for the red shift effect in absorption edge of ZnO.
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Structural and optical properties of ZnO nanostructures grown by Aerosol Spray pyrolysis: Candidates for room temperature methane and hydrogen gas sensing
Applied Surface Science, 2013Co-Authors: David E. Motaung, Ioannis Kortidis, S.s. Nkosi, Gerald F. Malgas, Bonex W. Mwakikunga, G.h. Mhlongo, Suprakas Sinha Ray, George KiriakidisAbstract:Abstract We report on the synthesis of ZnO films by Aerosol Spray pyrolysis method at different deposition times. The surface morphology, crystal structure and the cross-sectional analysis of the prepared ZnO films were characterized by X-ray diffraction (XRD), focused ion beam scanning electron microscopy (FIB-SEM), atomic force microscopy (AFM) and high resolution transmission electron microscopy (HR-TEM). XRD analysis revealed that the ZnO films are polycrystalline in nature. Structural analysis exploiting cross-sectional TEM profile showed that the films composed of nano-particles and columnar structures growing perpendicular to the substrate. AFM revealed that the columnar structures have a higher surface roughness as compared to the nanoparticles. The effect of ZnO crystallite size and crystallinity on the gas sensing performance of hydrogen and methane gases was also evaluated. Sensing film based on ZnO nanoparticles has numerous advantages in terms of its reliability and high sensitivity. These sensing materials revealed an improved response to methane and hydrogen gases at room temperature due to their high surface area, indicating their possible application as a gas sensor.
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Structural analysis of Aerosol Spray pyrolysis ZnO films exhibiting ultra low ozone detection limits at room temperature
Thin Solid Films, 2009Co-Authors: Ioannis Kortidis, K. Moschovis, F. A. Mahmoud, George KiriakidisAbstract:ZnO films grown by a home-made Aerosol Spray Pyrolysis (ASP) system at 350 °C have shown a characteristic columnar structure with an inhomogeneous layer structure that extends all the way to the surface. Surface morphology studies revealed grain sizes of the order of 80 nm and a highly porous structure which proved catalytic for the performance as gas sensing element. Conductometric ozone response tests have shown that the films of such a structure may be very effective in detecting ultra low ozone concentrations. The lowest ozone limit detected was 16 ppb at room temperature opening up the road for ultra sensitive inexpensive metal oxide ozone detectors.
Junxin Wang - One of the best experts on this subject based on the ideXlab platform.
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Aerosol Spray diverse mesoporous metal oxides from metal nitrates
Scientific Reports, 2015Co-Authors: Long Kuai, Baoyou Geng, Junxin Wang, Tian Ming, Caihong Fang, Jianfang WangAbstract:Transition metal oxides are widely used in solar cells, batteries, transistors, memories, transparent conductive electrodes, photocatalysts, gas sensors, supercapacitors, and smart windows. In many of these applications, large surface areas and pore volumes can enhance molecular adsorption, facilitate ion transfer, and increase interfacial areas; the formation of complex oxides (mixed, doped, multimetallic oxides and oxide-based hybrids) can alter electronic band structures, modify/enhance charge carrier concentrations/separation, and introduce desired functionalities. A general synthetic approach to diverse mesoporous metal oxides is therefore very attractive. Here we describe a powerful Aerosol-Spray method for synthesizing various mesoporous metal oxides from low-cost nitrate salts. During Spray, thermal heating of precursor droplets drives solvent evaporation and induces surfactant-directed formation of mesostructures, nitrate decomposition and oxide cross-linking. Thirteen types of monometallic oxides and four groups of complex ones are successfully produced, with mesoporous iron oxide microspheres demonstrated for photocatalytic oxygen evolution and gas sensing with superior performances.
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ultrasonic Aerosol Spray assisted preparation of tio2 in2o3 composite for visible light driven photocatalysis
Journal of Catalysis, 2014Co-Authors: Tian Ming, Junxin Wang, Jianfang WangAbstract:A TiO2/In2O3 composite photocatalyst has been prepared by using a facile ultrasonic Aerosol Spray (UAS)-assisted method. Results from scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and N2 adsorption–desorption measurements reveal that the as-prepared TiO2/In2O3 composite exhibits a porous structure and spherical morphology. The diameter ranges from tens of nanometers to several micrometers. According to the UV–vis diffuse reflectance spectra, the TiO2/In2O3 composite shows good visible-light absorption ability. The photocatalytic activity of the samples was evaluated by the decomposition of organic dyes in aqueous solutions under visible-light irradiation. All the composite samples show excellent photocatalytic performance. The effect of In2O3 content on the photocatalytic activity was also investigated. The best photocatalytic activity results from the TiO2/In2O3 sample with Ti:In molar ratio of 100:1. The UAS-assisted method can also be applied for the preparation of other composite semiconductor materials. It provides a general approach for scaling up the production of photocatalysts for practical applications.
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Ultrasonic Aerosol Spray-assisted preparation of TiO2/In2O3 composite for visible-light-driven photocatalysis
Journal of Catalysis, 2014Co-Authors: Tian Ming, Junxin Wang, Jianfang WangAbstract:A TiO2/In2O3 composite photocatalyst has been prepared by using a facile ultrasonic Aerosol Spray (UAS)-assisted method. Results from scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and N2 adsorption–desorption measurements reveal that the as-prepared TiO2/In2O3 composite exhibits a porous structure and spherical morphology. The diameter ranges from tens of nanometers to several micrometers. According to the UV–vis diffuse reflectance spectra, the TiO2/In2O3 composite shows good visible-light absorption ability. The photocatalytic activity of the samples was evaluated by the decomposition of organic dyes in aqueous solutions under visible-light irradiation. All the composite samples show excellent photocatalytic performance. The effect of In2O3 content on the photocatalytic activity was also investigated. The best photocatalytic activity results from the TiO2/In2O3 sample with Ti:In molar ratio of 100:1. The UAS-assisted method can also be applied for the preparation of other composite semiconductor materials. It provides a general approach for scaling up the production of photocatalysts for practical applications.
David Grosso - One of the best experts on this subject based on the ideXlab platform.
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Titania‐Based Spherical Mie Resonators Elaborated by High‐Throughput Aerosol Spray: Single Object Investigation
Advanced Functional Materials, 2018Co-Authors: Simona Checcucci, Thomas Bottein, Jean-benoit Claude, Thomas Wood, Magali Putero, Luc Favre, Massimo Gurioli, Marco Abbarchi, David GrossoAbstract:In the framework of photonics with all-dielectric nanoantennas, sub-micrometric spheres can be exploited for a plethora of applications including vanishing back-scattering, enhanced directivity of a light emitter, beam steering, and large Purcell factors. Here, the potential of a high-throughput fabrication method based on Aerosol-Spray is shown to form quasi-perfect sub-micrometric spheres of polycrystalline TiO2. Spectroscopic investigation of light scattering from individual particles reveals sharp resonances in agreement with Mie theory, neat structural colors, and a high directivity. Owing to the high permittivity and lossless material in use, this method opens the way toward the implementation of isotropic meta-materials and forward-directional sources with magnetic responses at visible and near-UV frequencies, not accessible with conventional Si- and Ge-based Mie resonators.
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Titania-Based Spherical Mie Resonators Elaborated by High-Throughput Aerosol Spray: Single Object Investigation
Advanced Functional Materials, 2018Co-Authors: Simona Checcucci, Thomas Bottein, Jean-benoit Claude, Thomas Wood, Magali Putero, Luc Favre, Massimo Gurioli, Marco Abbarchi, David GrossoAbstract:In the framework of photonics with all-dielectric nanoantennas, sub-micrometric spheres can be exploited for a plethora of applications including vanishing back-scattering, enhanced directivity of a light emitter, beam steering, and large Purcell factors. Here, the potential of a high-throughput fabrication method based on Aerosol-Spray is shown to form quasi-perfect sub-micrometric spheres of polycrystalline TiO2. Spectroscopic investigation of light scattering from individual particles reveals sharp resonances in agreement with Mie theory, neat structural colors, and a high directivity. Owing to the high permittivity and lossless material in use, this method opens the way toward the implementation of isotropic meta-materials and forward-directional sources with magnetic responses at visible and near-UV frequencies, not accessible with conventional Si- and Ge-based Mie resonators.
