Surface Plasmon Resonance Of Ag Research Articles

Integration of Ag Plasmonic Metal and WO3/InGaN Heterostructure for Photoelectrochemical Water Splitting.

In this study, a Ag/WO3/InGaN hybrid heterostructure was successfully developed by sputtering and molecular beam epitaxy techniques, to obtain unique Ag nanospheres adorned with cauliflower-like WO3 nanostructure over the InGaN nanorods (NRs). Exploiting the localized surface plasmon resonance of Ag, the Ag/WO3/InGaN heterostructure exhibited superior photoabsorption ability in the visible region (400-700 nm) of the solar spectrum, with a surface plasmon resonance band centered around 440 nm. Comprehensive analysis through photoluminescence spectroscopy, photocurrent measurements, and electrochemical impedance spectroscopy revealed that the Ag/WO3/InGaN hybrid heterostructure significantly enhances the charge carrier separation and transfer kinetics leading to improved overall photoelectrochemical (PEC) performance. The photocurrent density of the Ag/WO3/InGaN photoanode is 1.17 mA/cm2, which is about 2.72 times higher than that of pure InGaN NRs under visible light irradiation. The photoanode exhibited excellent stability for about 12 h. From the study, it has been found that the maximum applied bias photon-to-current efficiency (ABPE) is ∼1.67% at the applied bias of 0.6 V. The improved PEC water splitting efficiency of the Ag/WO3/InGaN photoanode is attributed to the synergistic effects of localized surface plasmon resonance (LSPR), efficient charge carrier separation and transport, and the presence of a Schottky junction. Consequently, the plasmonic metal-assisted heterojunction-based semiconductor Ag/WO3/InGaN demonstrates immense potential for practical applications in photoelectrochemical water splitting.

Synergistic effect of electrochemically fabricated polyaniline nanofibers and silver for efficient solar steam generation

Solar steam generation (SSG) has been recognized as a promising and green technology to resolve the scarcity of drinking water in the near future. On the other hand, there are still several challenges associated with SSG system to its practical utilization. Design of suitable photothermal materials with high solar absorption and conversion efficiency is one of the challenges associated with the SSG technology. Herein, we demonstrated a strategy for the fabrication of bilayer structure of porous polyaniline (PANI) nanofibers and conducting silver (Ag) on a carbon cloth (PANI/Ag@CC) substrate using a facile electrochemical deposition approach. As prepared binder-free PANI/Ag@CC showed an excellent steam generation rate of 2.21 kg/m2h with superior evaporation efficiency of 98.0 % under 1 sun illumination when used for the SSG application. Furthermore, the bilayered PANI/Ag@CC exhibited excellent durability, effective seawater desalination and wastewater purification. The superior SSG performance is associated with the synergistic effect of surface plasmon resonance of Ag and porous PANI nanofibers. Therefore, practically simple fabrication, outstanding evaporation rate and water purification properties convince that the PANI/Ag@CC structure can be a promising candidate for SSG applications.

Boosted visible-light-driven degradation over stable ternary heterojunction as a plasmonic photocatalyst: Mechanism exploration, pathway and toxicity evaluation

The incorporation of plasmonic metals into semiconductors forming heterojunction photocatalysts is a promising route to enhance the photocatalytic performance in visible light. In this work, we reported the visible-light-driven one-dimensional (1D) nanostick silver/silver sulfide (Ag/Ag2S) photocatalyst combining with two-dimensional (2D) nanosheet reduced graphene oxide intersected by hollow structure (h-RGO) was prepared via a feasible approach at room temperature. The density of Ag depositing on the surface of Ag2S was easily tuned by the concentration of sodium borohydride and the silicon dioxide nanospheres were employed as templates in the preparation of h-RGO by the layer-by-layer (LBL) assembly. The ternary plasmonic Ag/Ag2S/h-RGO photocatalysts exhibited better photocatalytic performance for degradation of naphthalene (95.95%) and 1-naphthol (98.65%) under visible light than the pure Ag2S, composite Ag/Ag2S and composite Ag/Ag2S/RGO. Localized surface plasmon resonance of Ag, heterojunction formed between Ag/Ag2S and RGO and the unique characteristics of h-RGO, which included higher specific surface areas, more efficient reflections of light and more active sites than RGO for boosting separation efficiency of charge carriers, were all responsible for such enhancement. By combining the characterization results with various computations, the mechanism, potential degradation pathways and the toxicity of the generated intermediates for photodegradation were examined. In addition to offering profound insight into the expansion of effective plasmonic photocatalysts with novel structures, the current study is beneficial to ease the environmental crisis to a certain extent.

Enhancement of Light Absorption in the Active Layer of Organic Solar Cells using Ag:SiO2 Core-Shell Nanoparticles

Organic solar cells still suffer from relatively low conversion efficiency despite significant progress. An Ag:SiO2 core-shell nanoparticle embedded inside the active layer of an organic solar cell is expected to enhance light absorption. Light absorption within the active layer consisting of 70 nm thickness PEDOT: PSS and P3HT: PCBM was calculated using the finite element method for a variable diameter of the silver core, the thickness of the SiO2 shell, and the relative position of nanoparticle inside the active layer. The diameter of the Ag nanoparticle varies from 20 to 50 nm, the thickness of SiO2 varies from 1 to 4 nm, and the position was shifted vertically to 70 nm. The maximum light absorption in the active layer is obtained for silver nanoparticles with a diameter of 40 nm and a SiO2 thickness of 1 nm. The optimum position of the core-shell nanoparticle was found to be not at the interface between the PEDOT: PSS and P3HT: PCBM layers but a little bit shifted down into P3HT: PCBM layer. The highest increase of light absorption, compared to without Ag:SiO2, is 210%, much higher than reported in the literature. Increasing absorption is related to the excitation of surface plasmon resonance of Ag:SiO2 nanoparticles leading to the local field and scattering enhancement in the active layer of the organic solar cell

Ag/rGO/Bi2WO6 nanocomposite as a highly efficient and stable photocatalyst for Rhodamine B degradation under visible light irradiation

An efficient Ag/rGO/Bi2WO6 nanocomposite was synthesized by the precipitation-photoreduction method. The resulting Ag/rGO/Bi2WO6 showed excellent photocatalytic activity for the photodegradation of Rhodamine B (RhB), with 15%Ag/rGO/Bi2WO6 photodegrading 96.97% of RhB in 180 min, which was 1.28, 1.09 and 1.05 times higher than that of Bi2WO6, Ag/rGO, and rGO/Bi2WO6, respectively. The effect of noble metal Ag's surface plasmon resonance and Schottky barrier, as well as the superior electron transfer ability of rGO, dramatically improved photo-generated electron-hole pair separation and transfer efficiency. In addition, the effects of pollutant concentration, pH, and catalyst dosage on Ag/rGO/Bi2WO6 photocatalytic performance also were explored. Furthermore, the free-radical trapping tests revealed that the primary active radicals in the catalytic system are hole (h+), superoxide radical (•O2−), and hydroxy radical (•OH). Additionally, after four recycling, the photocatalytic performance of the Ag/rGO/Bi2WO6 composite did not show a significant decline. As a result of this research, the Ag/rGO/Bi2WO6 catalyst, as developed, has a bright potential for environmental purifying.

Evaluation of SERS activity for cosputtered Ag-ZnX@PS (X = O, S, Se) composites: Carrier density dependence

Ag-ZnX (X = O, S, Se) composites coated on polystyrene (PS) arrays (Ag-ZnO@PS, Ag-ZnS@PS, Ag-ZnSe@PS) were successfully fabricated by using cosputtering technology. We found that ZnX doping decreased the carrier densities of these composites compared to that of pure Ag@PS, which was due to redistribution of electrons between Ag and ZnX. Thus, the carrier density of Ag was decreased, and the surface plasmon resonance (SPR) of Ag was redshifted in the Ag-ZnX composites. As the redshift of the SPR of Ag induced a high SPR contribution to the surface-enhanced Raman scattering (SERS), the SPR and charge transfer (CT) contributions were simultaneously increased with increasing carrier density in the Ag-ZnX composites. This study opens a new path to designing metal–semiconductor composites with controllable carrier density. Regulation of the carrier density will be of great help in understanding SPR and CT contributions.

Photodegradation and in‐Situ SERS Monitoring Properties of Ag@AgCl Anchored on Sea Urchin‐shaped Fe3O4@C/1D PANI Nanoparticles**

AbstractHere, sea urchin‐shaped nanoparticles were first fabricated by growing one dimensional polyaniline (1D PANI) nanowire array on carbon layer encapsulated Fe3O4 nanoparticles, and then Ag@AgCl photocatalyst were tightly anchored on the surface of PANI nanowire to form Fe3O4@C/1D PANI/Ag@AgCl bifunctional material as recyclable adsorption‐photocatalysts and surface enhanced Raman scattering (SERS) substrate to monitor photocatalytic degradation of dye molecules. Compared with Fe3O4@C/1D PANI, Ag@AgCl and Fe3O4@C/PANI/Ag@AgCl catalysts, the fast electron transfer characteristics of conductive 1D PANI nanowire array and the synergistic effect between the surface plasmon resonance of Ag and the photosensitive characteristic of AgCl, enabled the prepared Fe3O4@C/1D PANI/Ag@AgCl excellent adsorption‐photocatalytic efficiency for the degradation of RhB under visible‐light irradiation. PL spectra and a series of photoelectrochemical measurements were carried out to investigate the reasons for such enhanced photocatalytic activity and the possible improved photocatalytic degradation mechanism was proposed. Meanwhile, the detection of the presence of RhB and its degradation process were achieved with real‐time SERS technology employing the prepared Fe3O4@C/1D PANI/Ag@AgCl photocatalyst itself as the substrate. All the results made it great promise for simultaneously monitoring and removal of organic contaminants in water.

Weibull Modeling of Controlled Drug Release from Ag-PMA Nanosystems.

Traditional pharmacotherapy suffers from multiple drawbacks that hamper patient treatment such as antibiotic resistances or low drug selectivity and toxicity during systemic applications. Some functional hybrid nanomaterials are designed to handle the drug release process under remote-control. More attention has recently been paid to synthetic polyelectrolytes for their intrinsic properties which allow them to rearrange into compact structures, ideal to be used as drug carriers or probes influencing biochemical processes. The presence of Ag nanoparticles (NPs) in the Poly methyl acrylate (PMA) matrix leads to an enhancement of drug release efficiency, even using a low-power laser whose wavelength is far from the Ag Surface Plasmon Resonance (SPR) peak. Further, compared to the colloids, the nanofiber-based drug delivery system has shown shorter response time and more precise control over the release rate. The efficiency and timing of involved drug release mechanisms has been estimated by the Weibull distribution function, whose parameters indicate that the release mechanism of nanofibers obeys Fick’s first law while a non-Fickian character controlled by diffusion and relaxation of polymer chains occurs in the colloidal phase.

Near-IR reconfigurable 1D Ag grating Fabry-Perot absorber hybridized with phase-change material GSST.

Chalcogenide phase-change materials (PCMs) offer a unique feature that can be used to dynamically control the response of the photonic devices and achieve fast, nonvolatile, reversible, multilevel, and specific optical modulation. The phase-change material Ge2Sb2Se4Te1 (GSST) has recently received a lot of attention due to the large index contrast between its amorphous and crystalline states with significantly low optical loss in the optical to near-IR spectrum. In this paper, we propose a tunable and reconfigurable hybrid PCM plasmonic nanostructure composed of a spacer layer of GSST sandwiched between a Ag back reflector and a 1D Ag Fabry-Perot grating structure. We use the finite element method (FEM) to numerically calculate the light absorption, absorption contrast, and figure of merit of the plasmonic nanostructure for both the amorphous and crystalline state of the GSST. Our calculations show that with constant structural variation the observed multimode absorption is drastically modified when the GSST undergoes a phase change from the amorphous to the crystalline state. The absorption contrast spectrum, which is defined as the absorption difference between the amorphous and crystalline state of GSST, shows four extrema modes between 70% and 89%. The figure of merit spectrum shows two large values of 44.39 and 37.78 at the 1502 nm and 2063 nm wavelengths, respectively. We also address the observed modes in the absorption contrast spectrum through spatial representation of the enhanced electric field distribution at their corresponding wavelengths. We show how the phase change in the GSST spacer can control the coupling between the optical cavity modes and the Ag surface plasmon resonance modes in the cavities and GSST spacer strip boundaries. The findings in this paper may open new avenues toward the design of next-generation photonic systems such as thermal emission controllers, sensors, ranging holograms, modulators and optical detection devices.

TiO2 and Ag-TiO2 nanomaterials for enhanced photocatalytic and antioxidant activity: Green synthesis using Cucumis melo juice

This study illustrates preparation of well-formed TiO2 and Ag/TiO2 nanoparticles (NPs) by green combustion process using Cucumis melo (Muskmelon) juice as unique fuel. Polycrystalline Ag/TiO2 NPs outline the superior photocatalytic action towards the degradation of methylene blue dye and antioxidant activity through hindrance of free radical scavenging. The PXRD pattern illustrates the existence of Ag in the TiO2 crystal lattice with the average crystallite measure of 9.09 nm and 22.8 nm for TiO2 and Ag/TiO2 respectively. FTIR spectral studies showed a decrease in the intensity upon doping with Ag owing to the arrangement of Ag NPs on the surface of TiO2 NPs. The TEM image of Ag/TiO2 exhibited almost spherical shape with average particle measure of 9.12 nm. Further, HRTEM studies evidence enhancement of the lattice fringe width upon doping and d-spacing values are in conformity with XRD results illustrating successful doping of Ag into TiO2 lattice. PL spectrum of both the NPs exhibited intense peak at 458 nm (2.69 eV) and weak peaks at 486 nm (2.53 eV) and 700 nm (1.76 eV) in the visible region. Ag/TiO2 NPs showed predominant photocatalytic property for the MB dye decomposition compared to TiO2 NPs. This is possibly owing to aid of Ag Surface Plasmon Resonance in expanding the light assimilation of TiO2 NPs from near UV region to visible range driving to better light-absorbing capability and considerably enhances charge separation in TiO2 due to doping. The results manifested that Ag/TiO2 NPs possess conformity surface structure, better photocatalytic property compared to un-doped TiO2. Both the NPs proved to have considerable DPPH free radical scavenging activities.

Excellent Antimicrobial Activity of Fe3O4/SiO2/Ag Nanocomposites

In this study, a new antimicrobial agent was developed through a synthesis of Fe3O4/SiO2/Ag double nanocomposites using the sol–gel method. The prepared samples were characterized using XRD, SEM, FTIR, UV-Vis, VSM, and antibacterial test. The data analysis results for the Fe3O4/SiO2/Ag composites showed that Fe3O4, SiO2, and Ag constructed respective spinel cubic, orthorhombic, and amorphous structures in nanometric size. The saturation magnetization of Fe3O4/SiO2/Ag nanocomposites decreased due to the increase in the Ag content. Interestingly, the Fe3O4/SiO2/Ag nanocomposites presented excellent microbial activity. Ag deposition on the Fe3O4/SiO2surface enhanced the antimicrobial activity of nanocomposites because Ag oxidized to Ag[Formula: see text] ion to produce a toxic effect in the cells of microorganisms. Furthermore, the Ag[Formula: see text] ion created the –S–Ag bond chain and deactivated the microorganism cells. Furthermore, surface plasmon resonance of Ag had an impact on the formation of photo-induced electrons, which produced superoxide radical anions, [Formula: see text] generating a collapsing force that causes the death of microorganisms.

Novel Ag decorated, BiOCl surface doped AgVO3 nanobelt ternary composite with Z-scheme homojunction-heterojunction interface for high prolific photo switching, quantum efficiency and hole mediated photocatalysis

A ternary composite Ag@AgVO3/BiOCl possessing homojunction-heterojunction interface with varied BiOCl concentration was obtained through a facile hydrothermal route. Ag deposition in Ag@AgVO3 nano-belt was achieved through in-situ generation and deposition of Ag forming a homojunction. Whereas Ag@AgVO3/BiOCl heterojunction was constructed through the surface doping. This unique two-way interaction and the interface formation were revealed through the electron microscope and crystallographic analysis. The localized surface plasmon resonance of Ag and the efficient orbital mixing with BiOCl of 1:1 B/Ag@A compound has imparted a remarkable light harvesting and photo switching ability in the ternary composite material. Conductive nature of the Ag nanoparticle has promoted light absorption in the visible region and reduced the charge transfer resistance. Reduction of width in space charge region along with the increase in the amount of surface charge carrier has resulted in an outstanding increment in photocurrent. The solar photocatalysis evaluated against the aqueous phase removal of methyl orange and Bisphenol A showed 100 % and 51 % removal in 50 and 240 min, respectively. Studies were extended to understand the sensitization effect of dye. Theoretical modelling of band structure drawn from charge trapping experiments showed the prevalence of Z-scheme mechanism with holes mediated catalytic degradation. Improved charge harvest, separation and transmission has inserted a higher quantum efficiency in the material. BPA removal was enhanced to 82 % after the peroxide activation.

Ag quantum dots modified hierarchically porous and defective TiO2 nanoparticles for improved photocatalytic CO2 reduction

Photocatalytic reduction of CO2 into high added-value chemical products has received special attention. Herein, we designed a novel hierarchically porous and defective TiO2 modified by Ag quantum dots via a hydrothermal process assisted with organic surfactant and subsequently in-situ photodeposition method. The obtained Ag quantum dots modified TiO2 (Ag/TiO2) shows excellent and stable photocatalytic activity in CO2 reduction. In addition, the competing H2 evolution can be completely suppressed. The super photocatalytic activity can be ascribed to the design of hierarchically porous, the intrinsic defects in TiO2, the localized surface plasmon resonance of Ag and the synergetic effect between Ag quantum dots and defective TiO2, which jointly improves the CO2 adsorption performance, enhances visible light absorption capacity and accelerates the separation of photogenerated charges. This work may provide a strategy to design and synthesis defective and hierarchically porous metal oxides for photocatalytic CO2 reduction.

Preparation and photocatalytic performance of silver nanocrystals loaded Cu2O-WO3 composite thin films for visible light-active photocatalysis

In this work, we demonstrate a thin film-based plasmonic metal-loaded Z-scheme heterojunction composite photocatalyst Ag@Cu2O-WO3 by sputtering with enhanced photocatalytic activity upon visible-light irradiation. The amorphous WOx/Cu-WOx film has transformed into crystalline Cu2O embedded monoclinic-WO3 composite (Cu2O-WO3) during the rapid thermal annealing. The Cu2O-WO3 films showed optical bandgap ∼2.7 eV, and good optical transmittance ∼85 % @550 nm. The Ag@Cu2O-WO3 composite films show enhanced photocatalytic activity with a methylene blue degradation rate constant 3.43 × 10−3 min-1, which is ∼3.75 times higher than pure monoclinic-WO3 films. The average charge carrier lifetime of the Ag@Cu2O-WO3 is 5.24 ns, which is 1.63 times higher than that of Cu2O-WO3. The enhanced photocatalytic activity is owing to the efficient photogenerated electrons-holes separation through the combination of Z-scheme heterostructure (Cu2O-WO3) and localized surface plasmon resonance of Ag. Thus, this work provides new insight into the fabrication of very sustainable, optically transparent, reusable, and cost-effective thin film-based photocatalysts.

Construction of Z-scheme Ag/In2S3/ZnO nanorods composite photocatalysts for degradation of 4-nitrophenol

Herein, Ag/In2S3/ZnO nanorods (NRs) composite photocatalysts were successfully prepared via simple methods. Significantly, hydroxyl radical active substances were found in the electron spin resonance tests of In2S3/ZnO NRs and Ag/In2S3/ZnO NRs, which indicates that the oxidation reaction that oxidizes water or hydroxide ions into hydroxyl radicals occurs on the valence band of ZnO NRs. It suggests that Z-scheme heterojunction was successfully constructed. In the photocatalytic experiments of degrading 4-nitrophenol (PNP), the Ag/In2S3/ZnO NRs composite exhibits higher photocatalytic activity than ZnO NRs, In2S3, Ag/ZnO NRs and In2S3/ZnO NRs. The characteristic peak of PNP disappears completely in 50 min. The enhanced photocatalytic performance can be attributed to the formation of Z-scheme heterojunction between ZnO NRs and In2S3. In addition, local surface plasmon resonance of Ag and Schottky junction formed between Ag and In2S3 also promote the photocatalytic activity.

Helium droplet assisted synthesis of plasmonic Ag@ZnO core@shell nanoparticles

Plasmonic Ag@ZnO core@shell nanoparticles are formed by synthesis inside helium droplets with subsequent deposition and controlled oxidation. The particle size and shape can be controlled from spherical sub-10 nm particles to larger elongated structures. An advantage of the method is the complete absence of solvents, precursors, and other chemical agents. The obtained particle morphology and elemental composition have been analyzed by scanning transmission electron microscopy (STEM) and energy dispersive X-ray spectroscopy (EDS). The results reveal that the produced particles form a closed and homogeneous ZnO layer around a 2–3 nm Ag core with a uniform thickness of (1.33 ± 0.15) nm and (1.63 ± 0.31) nm for spherical and wire-like particles, respectively. The results are supported by ultraviolet photoelectron spectroscopy (UPS), which indicates a fully oxidized shell layer for the particles studied by STEM. The plasmonic properties of the produced spherical Ag@ZnO core@shell particles are investigated by two-photon photoelectron (2PPE) spectroscopy. Upon excitation of the localized surface plasmon resonance in Ag at around 3 eV, plasmonic enhancement leads to the liberation of electrons with high kinetic energy. This is observed for both Ag and Ag@ZnO particles, showing that even if a Ag cluster is covered by the ZnO layer, a plasmonic enhancement can be observed by photoelectron spectroscopy.

Enhanced Ag@SnO2 Plasmonic Nanoparticles for Boosting Photoluminescence and Photocurrent Response of ZnO Nanorod UV Photodetectors

Ag@SnO2 nanoparticles (NPs) have been prepared by varying the concentration of sodium stannate trihydrate coated onto ZnO nanorods as the photoanode for photoelectrochemical self-powered ultraviolet photodetectors (UVPDs). Their structure, morphology, and optical properties were investigated. Compared with ZnO nanorods (NRs), the Ag@SnO2-coated ZnO NRs exhibited ultraviolet photoluminescence enhanced by nearly six orders of magnitude when 2 mL 40 mM sodium stannate trihydrate was used. This enhanced photoluminescence intensity is ascribed to the localized surface plasmon resonance of Ag in Ag@SnO2. Moreover, when varying the sodium stannate trihydrate concentration in the Ag@SnO2 NPs, the UVPD with 2 mL 40 mM sodium stannate trihydrate exhibited a high photocurrent density (Jsc) of 5.81 mA cm−2 compared with 2.34 mA cm−2 for the ZnO UVPD. This boost in Jsc is attributed to enhanced UV light harvesting and reduced charge recombination. Furthermore, this device also reached a high on/off ratio of 3885 and fast response time compared with the ZnO UVPD. Finally, such photoanodes formed from Ag@SnO2 nanoparticles coated on ZnO NRs are promising for use in photoelectrochemical-type self-powered UV photodetectors.

Boosting Visible-Light Photodegradation over Ternary Strategy-Engineered Metal–Organic Frameworks

Defect engineering on metal–organic frameworks (MOFs) has attracted great interest in photocatalysis by improving charge-separation efficiency. However, it inevitably brings the disadvantage of lowered light absorption ability. Herein, we successfully overcome the problem by introducing the surface plasmon resonance (SPR) effect and heterostructure by depositing Ag/AgCl onto defect-engineered UiO-66-NH2 to form UiO-66-NH2/Ag/AgCl. Our findings indicate that structural linker defects on UiO-66-NH2 benefit to form metallic Ag and strengthen the Ag/AgCl interaction, which consequently will pronounce the Ag SPR effect and reduce the height of the Schottky barrier of Ag/AgCl. The former can significantly promote the visible-light absorption ability, while the latter, combined with defect engineering and formation of the AgCl/UiO-66-NH2 heterostructure, greatly improves the charge-separation efficiency. Accordingly, this ternary strategy significantly boosts the visible-light photocatalytic activities of the composites for both RhB and p-chlorophenol degradation. We hope that this work will bring novel insights to design other MOF-based photocatalytic systems.

Photogenerated Oxygen Vacancies in Hierarchical Ag/TiO2 Nanoflowers for Enhanced Photocatalytic Reactions.

Oxygen vacancy (Vo) creation and morphology controlling make significant contributions to the electronic and structural regulation of metal oxide semiconductors, yet an investigation about convenient approaches for fabricating hierarchical catalyst with abundant oxygen vacancies still has significant challenges. Here, we report a unique method to create abundant oxygen vacancies in hierarchical Ag/TiO2 nanoflowers during photocatalytic reaction, which is accompanied by light absorption variation and surface plasmon resonance (SPR) enhancement. Its high efficiency of photocatalytic H2 evolution (the highest apparent quantum yield reaches 3.2% at 365 nm) and rhodamine B degradation can be considered as benefits from the synergistic effects of the well-arranged hierarchical structure, the photogenerated oxygen vacancies, and the SPR of cocatalyst Ag. This work proposes an effective strategy to optimize the synthesis of regular hierarchical structures and enriches the research on the vital function of oxygen vacancies in photocatalytic reactions.

Surface plasmon resonance amplified efficient polarization-selective volatile organic compounds CdSe-CdS/Ag/PMMA sensing material

Volatile organic compounds (VOCs) are potentially dangerous to the environment and human health. The developed sensing template in this study was prepared by a one-step process on a glass substrate using the electrospinning technique. The sensing material made of the uniaxial aligned CdSe-CdS/Ag/PMMA composite scaffold consists of CdSe-CdS core-shell quantum rods, silver nanoparticles (Ag NPs), and poly(methyl methacrylate) (PMMA) nanofibers. Increasing the specific surface area is beneficial for VOCs harvesting; therefore, the uniaxial aligned CdSe-CdS/Ag/PMMA composite scaffold was slightly treated with UV-ozone etching, and thus efficiently enhancing the extinction changes of VOCs. Also, a high VOC detection capability was demonstrated by the polarization response and Ag surface plasmon resonance of the nanocomposite. A series of typical VOCs and alcoholic VOCs were used for the VOCs sensor practical tests. This VOC sensor achieved a spectacular detection limit of 100 ppm for butanol and 500 ppm for chlorobenzene. The uniaxial aligned CdSe-CdS/Ag/PMMA composite scaffold is a newly designed nanocomposite and can reach the market demands comparing to other commercial high sensitive VOC sensors.