Surface Plasmon Resonance Effect Research Articles

Ion-engineered solar desalination: Enhancing salt resistance and activated water yield

Solar desalination, which relies on localized heating for interfacial water evaporation, is regarded as a promising and sustainable approach for freshwater production. Significant progress has been achieved in developing high-performance solar-driven interfacial vapor generators (SIVGs), however, their performance in high-concentration brine remains unsatisfactory. Herein, a novel SIVG is proposed as a candidate with advanced ionization engineering design for solar desalination, which exhibits enhanced desalination performance. The design of ionization engineering can promote salt-blocking effects through electrostatic attraction between salt ions in seawater and polymer chains of hydrogel-based evaporator, and high-continuity porous structures, which also contributes to a high evaporation performance by increasing the production of activated water molecules. Furthermore, the introduction of CuO nanoparticles with excellent localized surface plasmon resonance effect enables the light-absorbing copper-based hydrogel (LACH) to achieve an impressive sunlight absorptance rate of 95 %. The evaporation rate and energy efficiency of LACH reach a remarkable 3.93 kg·m−2·h−1 and 93.5 % in simulated brine (3.5 wt% NaCl solution) under one-sun illumination. The salt-resistant LACH-related SIVG is one of ideal candidates for sustainable freshwater harvesting over extended periods. This study is expected to offer valuable insights for advancing the research and development of next-generation solar desalination devices.

Nano-silver@polydopamine carbonized melamine foam supported polyethylene glycol phase change materials: With simultaneous improved photo-thermal conversion ability

Ag nanoparticles are commonly used for phase change material (PCM) modification to improve the photo-thermal convertibility in composite phase change materials (CPCM) owing to enhance carrier's ability to absorb photons by virtue of its unique localized Surface Plasmon Resonance effect (LSPR). Currently, redox method is considered to be the most effective method for the preparation of Ag nano-coating. However, it is still challenging to obtain a dense and uniform Ag nano-coating on the carrier surface due to the difference in the binding force between Ag nanoparticles and different carriers. Herein, a new preparation strategy is demonstrated, in which the carrier is pre-modified by adding a polydopamine (PDA) coating to enhance the bonding between the carrier and the silver nanoparticles, and then a stable three-dimensional silver nano-conducting network is obtained by redox. Consequential stable architecture contributes to polyethylene glycol (PEG) loadings reach 98%, simultaneously with an ultra-high photo-thermal conversion efficiency of 97.9%. Furthermore, this paper demonstrates the effect of carbonization temperature on the flexibility of melamine carbon foam (CMF), and different nano-Ag concentrations on the thermal conductivity of CPCM. This finding provides valuable guidance for the engineering of high photo-thermal conversion performance CPCM and strengthens their practical implementation in solar energy storage and thermal management.

Photothermal-regulated selective desorption of enantiomers from Ag/Ni3S2 nanosheet-covered Ni foam

Separation of racemates is critically important in the chemical, agrochemical and pharmaceutical industries, since enantiomers may differ in biological interactions, pharmacology, and toxicity. However, the methods for highly enantioselective separation are still insufficient. In this study, we prepared Ni3S2 nanosheet arrays with excellent photothermal properties using Ni foam as the precursor. The PT enantioselective desorption approach is based on a Ni3S2 NSA decorated with Ag nanoparticles modified with D-penicillamine as the enantioselective substrate. Finite-difference time-domain simulation was used to probe the optimal number, shape, and distribution of Ag NP to optimize the localized surface plasmon resonance and photothermal effect. The enantiomers of 3,4-dihydroxyphenylalanine were used as models to demonstrate enantioselective separation based on the different number of stable hydrogen bonds between the homochiral substrate and each enantiomer. This enantioselective desorption approach has the advantages of efficiency, low cost, and recyclability, and provides a new solution for separating racemic molecules.

Pillar[5]arene functionalized Au NPs and BiOX (Cl/Br/I) heterojunction constructed the enhanced photo-electrochemical sensor for ultrasensitive detection of serotonin

The functional photoelectric materials based on bismuth oxyhalides (BiOX, X = Cl, Br and I) have been widely used in the field of photo-electrochemistry (PEC) due to their excellent physical, chemical and optical properties. Herein, a series of BiOX nanoflowers conjugated water-soluble pillar[5]arenes functionalized Au (Au@WP5/BiOX) modified PEC sensor are constructed and investigated for the PEC detection of serotonin. Upon exploring the physical properties, such as size, visible light absorption capacity, band gap and impedance, of the three BiOX materials, it is discovered that BiOBr is more effective in detecting 5-HT due to its high redox ability, moderate band gap (∼2.03 eV), and low impedance. BiOBr can provide a high and stable starting photocurrent compared to the other two bismuth oxyhalides. When used in acidic or neutral environments, 5-HT with a positive charge can undergo electrostatic adsorption and host-guest complexation behavior with WP5, which has a negative charge. By using WP5, the recognition ability of the material to 5-HT molecules can be enhanced, and the adsorption of 5-HT molecules on Au@WP5/BiOBr can be accelerated. The local surface plasmon resonance effect (LSPR) of gold nanoparticles (Au NPs) can accelerate the electrochemical reaction rate and charge transfer rate, which ultimately leads to the amplification of the photocurrent signal. As a result, the 5-HT detection sensor based on Au@WP5/BiOBr has a wide detection range from 0.01 to 100 μM and a low detection limit of 3 nM (S/N = 3) compared to other sensors, including Au@WP5/BiOCl and Au@WP5/BiOI. The proposed PEC sensor also exhibits good stability and selectivity, making it a promising strategy for detecting biological small molecules using pillar[5]arene functionalized PEC active materials.

Advanced multifunctional Co/N co-doped carbon foam-based phase change materials for wearable thermal management

To cope with the complex and changeable extreme environments, extending multifunctionality is crucial for potable smart wearable composite phase change materials (PCMs). Herein, we developed advanced Co/N co-doped carbon foam-based multifunctional “five-in-one” composite PCMs integrating dual-temperature thermal management, light-triggered heating, waterproof, flame retardant, and microwave absorption through high-temperature calcination of melamine foam@ZIF67 and melting encapsulation of paraffin wax (PW). Benefiting from the strong full-spectrum absorption, fast photon and phonon transport, and local surface plasmon resonance effect, our designed foam-based composite PCMs exhibited an ultrahigh photothermal conversion efficiency of 95.17 %. More importantly, foam-based composite PCMs demonstrated excellent thermal management, structural stability and thermal storage stability after undergoing 300 heating–cooling cycles. Furthermore, foam-based composite PCMs showed superior microwave absorption (RLmin = -57.93 dB), good flame retardancy and satisfactory hydrophobicity (contact angle > 100°). Thus, our developed multifunctional foam-based composite PCMs provide great potential for personalized thermal management and anti-radiation smart wearables even in harsh environments (e.g., rain, snow, sweat, fire, extreme cold, extreme heat and electromagnetic interference), creating a versatile platform for smart wearable light-triggered phase change heater with on-demand properties.

Polycarboxyl ionic liquid functionalized Yb-MOFs nanoballs based dual-wavelength responsive photoelectrochemical aptasensor for the simultaneous determination of AFB1 and OTA

Developing an accurate and precise approach for the simultaneous detection of ochratoxin A (OTA) and aflatoxin B1 (AFB1) is significant for food safety surveillance. Herein, a photoelectrochemical sensing platform was constructed based on polycarboxylic ionic liquid functionalized metal-organic framework integrated with gold nanoparticles (Yb-MOFs@AuNPs). Sulfhydryl functionalized hairpin DNA (hDNA) was immobilized on a Yb-MOFs@AuNPs modified glassy carbon electrode (GCE) surface through Au-S bond. After blocking residual active binding sites with BSA, gold nanoparticles-labeled AFB1 aptamer (AuNPs-Apt 1) and gold nanorods-labeled OTA aptamer (AuNRs-Apt 2) were introduced to construct a photoelectrochemical aptasensor for the simultaneous determination of AFB1 and OTA. Due to the surface plasmon resonance effect and the nanometer size effect of gold nanomaterials, the photoelectrochemical aptasensor can output photocurrent responses as being excited with different wavelengths at 520 nm and 808 nm, respectively. When the AFB1 and OTA concentration in the range of 0.001–50.0 ng mL−1, a good linear relationship between the photocurrent difference (ΔI) before and after recognizing targets and the logarithm of AFB1 or OTA concentration was obtained. The detection limits for AFB1 and OTA were 0.40 pg mL−1 and 0.19 pg mL−1, respectively. AFB1 and OTA in corn samples were detected simultaneously by the photoelectrochemical aptasensor.

Highly selective colorimetric determination of glutathione based on sandwich-structured nanoenzymes composed of gold nanoparticle-coated molecular imprinted metal-organic frameworks.

Asandwich-structured composite nanoenzyme (NH2-MIL-101(Fe)@Au@MIP) was prepared using molecularly imprinted polymers, metal-organic frameworks, and gold nanoparticles and a highly selective glutathione (GSH) colorimetric sensor was constructed. The inner part of the composite nanoenzymes is a metal-organic framework loaded with gold nanoparticles (AuNPs), NH2-MIL-101(Fe)@Au, which has superior peroxidase-like activity compared with NH2-MIL-101(Fe). This is due to the surface plasmon resonance effect of AuNPs. GSH can form strong Au-S bonds with AuNPs, which can significantly reduce the enzymatic activity of NH2-MIL-101(Fe)@Au, thereby changing the absorbance at 450nm of the sensing system. The degree of change in absorbance is correlated with the concentration of GSH. In the outer part, the molecularly imprinted polymer with oxidized glutathione (GSSG) as a dummy template provided specific pores, which significantly improved the selectivity of the sensing system. The sensor showed good GSH sensing performance in the range 1 ~ 50μM with a lower limit of detection (LOD) of 0.231μM and good sensing performance in fetal bovine serum, indicating its highpotential for clinical diagnostic applications.

Boosting N[tbnd]N tri-bond activation and NH3 generation rate through simple surface Ag modification

NH3 photosynthesis from nitrogen remains a big challenge due to the extreme difficulty for the activation of NN bond. In this work, Ag-modified MoO3·0.55 H2O nanorods (named as Ag@Mo) are prepared by a simple photoreduction method. Under visible light (λ ≥ 420 nm) for 60 min, the NH3 yield over 2%Ag@Mo (molar ratio of Ag to MoO3·0.55 H2O) reaches 242.0 μmol·gcat−1, which is about 2.8 times higher than MoO3·0.55 H2O under the same conditions. The effect of Ag modification on photocatalytic ammonia synthesis is explored through experiments and theoretical calculations. The excellent photocatalytic performance is mainly attributed to the localized surface plasmon resonance effect of Ag and the successful construction of Mott-Schottky junction, which improves light utilization efficiency and reduces carrier recombination efficiency, respectively. Moreover, density functional theory calculations theoretically prove that over Ag@Mo, Ag provides new adsorption sites, and the NN tri-bond length is elongated by about 16.2%, confirming that Ag modification obviously promotes the activation of NN tri-bond. The ammonia generation rate is obviously higher than the previously reported results.

Periodic Folded Gold Nanostructures with a Sub-10 nm Nanogap for Surface-Enhanced Raman Spectroscopy.

Surface-enhanced Raman spectroscopy has emerged as a powerful spectroscopy technique for detection with its capacity for label-free, nondestructive analysis, and ultrasensitive characterization. High-performance surface-enhanced Raman scattering (SERS) substrates with homogeneity and low cost are the key factors in chemical and biomedical analysis. In this study, we propose the technique of atomic force microscopy (AFM) scratching and nanoskiving to prepare periodic folded gold (Au) nanostructures as SERS substrates. Initially, folded Au nanostructures with tunable nanogaps and periodic structures are created through the scratching of Au films by AFM, the deposition of Ag/Au films, and the cutting of epoxy resin, reducing fabrication cost and operational complexity. Periodic folded Au nanostructures show the three-dimensional nanofocusing effect, hotspot effect, and standing wave effect to generate an extremely high electromagnetic field. As a typical molecule to be tested, p-aminothiophenol has the lowest detection limit of up to 10-9 M, owing to the balance between the electromagnetic field energy concentration and the transmission loss in periodic folded Au nanostructures. Finally, by precisely controlling the periods and nanogap widths of the folded Au nanostructures, the synergistic effect of surface plasmon resonance is optimized and shows good SERS properties, providing a new strategy for the preparation of plasmonic nanostructures.

Molecular Dynamics Simulation Combined with Near-Field Electromagnetic Analysis for Ultrashort-Pulsed Light-Induced Plasmonic Nanobubbles.

Ultrashort-pulsed light-induced nanobubbles gain great attention in research fields such as cancer therapy, optical imaging, and drug delivery. However, the mechanism governing the nucleation and growth of nanobubbles remains controversial. In this study, a molecular dynamics simulation combined with near-field electromagnetic theory is developed to investigate the influence of the localized surface plasmon resonance effect (LSPR) on nanobubble nucleation under various time-length pulsed light and to reveal the energy transfer differences during the nanobubble generation process. The results show that when silver nanoparticles (NPs) are irradiated by a 5 ps shorter-pulsed light, the temperature of the water layer adjacent to the nanoparticle surpasses that of the nanoparticle itself and reaches the spinodal temperature. This leads to nanobubbles' rapid nucleation at approximately 20 ps, which is 80 ps earlier than that irradiated by a 100 ps longer-pulsed light. Comparatively, during longer-pulsed light irradiation, a slower increase in both the temperature of the silver NPs and the water layer results in delayed nucleation of nanobubbles. Therefore, the plasmonic nanobubbles (PNBs) were observed around in 74 and 100 ps when irradiated by 50 and 100 ps longer-pulsed light, respectively. Moreover, the result indicates that the LSPR-induced enhanced electric field by shorter-pulsed light (5 ps) is 2.1 × 1010 V/m, which can accelerate the motion of water molecules surrounding silver NPs, resulting in rapid generation of nanobubbles. However, the intensities of the resonant electric field drop to 5.6 × 109 and 5.0 × 109 V/m when the duration times of pulsed light are 50 and 100 ps, respectively. These results indicate that the energy transfer mechanism of plasmonic nanobubbles (PNBs) under ultrashort-pulsed light irradiation might be very different from that of thermally mediated nanobubbles (TNBs). This work provides new insights into understanding the generation of PNBs induced by ultrashort-pulsed light.

Broadband, Plasmon‐Modified SnSe2 Photodetector Based on LNOI Thin‐Film Platform

AbstractLithium niobate on insulator (LNOI) is widely recognized as an essential optoelectronic integration platform due to its unique ferroelectric properties and photorefractive effect. However, the wide bandgap and weak absorption of lithium niobate limit its further application in integrated photodetection field. To address this issue, encapsulating silver nanoparticles within the LNOI structure are proposed to manipulate the light field distribution of modified lithium niobate through the localized surface plasmon resonance (LSPR) effect and utilize the modified lithium niobate thin film as a functional substrate to tailor the optoelectronic properties of surface SnSe2 nanosheets, significantly enhancing their photodetection capabilities. The photocurrent of the SnSe2 photodetector based on LNOI with embedded Ag nanoparticles is enhanced by up to 1912 times compared to that on the original LNOI under the same conditions, which represents the highest reported plasmonic‐induced photodetection enhancement. This work deepens the basic research on plasmonic‐modified 2D materials and ferroelectric materials, which promotes the development of on‐chip photodetectors and the realization of fully functional photonic circuits that integrate all essential components on a single chip.

A nonmetallic plasmonic catalyst for photothermal CO2 flow conversion with high activity, selectivity and durability

The meticulous design of active sites and light absorbers holds the key to the development of high-performance photothermal catalysts for CO2 hydrogenation. Here, we report a nonmetallic plasmonic catalyst of Mo2N/MoO2-x nanosheets by integrating a localized surface plasmon resonance effect with two distinct types of active sites for CO2 hydrogenation. Leveraging the synergism of dual active sites, H2 and CO2 molecules can be simultaneously adsorbed and activated on N atom and O vacancy, respectively. Meanwhile, the plasmonic effect of this noble-metal-free catalyst signifies its promising ability to convert photon energy into localized heat. Consequently, Mo2N/MoO2-x nanosheets exhibit remarkable photothermal catalytic performance in reverse water-gas shift reaction. Under continuous full-spectrum light irradiation (3 W·cm−2) for a duration of 168 h, the nanosheets achieve a CO yield rate of 355 mmol·gcat−1·h−1 in a flow reactor with a selectivity exceeding 99%. This work offers valuable insights into the precise design of noble-metal-free active sites and the development of plasmonic catalysts for reducing carbon footprints.

Facile Synthesis of a Novel AgIO3/CTF Heterojunction and Its Adsorption-Photocatalytic Performance with Organic Pollutants.

With the development of modern industry, the issue of water pollution has garnered increasing attention. Photocatalysis, as a novel green environmental technology that is resource-efficient, environmentally friendly, and highly promising, has found extensive applications in the field of organic pollutant treatment. However, common semiconductor materials exhibit either a relatively low photocatalytic efficiency in the visible light range or an inefficient separation of photogenerated charges, resulting in their limited ability to harness solar energy effectively. Consequently, the development of new photocatalysts has become a pivotal focus in current photocatalysis research to enhance solar energy utilization. This research provides a brief explanation of the photocatalytic mechanism of the AgIO3/CTF heterojunction photocatalyst. Due to the localized surface plasmon resonance (LSPR) effect, the Ag nanoparticles demonstrate significant absorption in the visible light region, playing a crucial role in the highly efficient photocatalytic reduction of organic pollutants.

Highly Efficient Red, Green, and Blue Inverted Top‐Emitting Organic Light‐Emitting Diodes with Microstructured TiN Substrate

The morphological and optical properties of microstructured silicon substrates (M–Si) and inverted top‐emitting organic light‐emitting diodes (ITOLEDs) based on the M–Si/Ti/TiN/Al composite electrodes are studied. The developed M–Si/Ti/TiN/Al composite electrodes function well in improving the performance of red, green, and blue ITOLED. The Al thin film deposited on TiN silicon substrate could significantly improve the reflectivity of the electrode, and the microstructured substrate could further increase the reflective path for lights inside OLEDs. Meanwhile, by adopting a light output‐coupling layer on top of the device and using the localized surface plasmon resonance effect of the top‐emitting structure, the angle‐dependent effect of ITOLEDs based on the composite electrodes is reduced. Through employing the M–Si/Ti/TiN/Al composite electrodes, all the red, green, and blue OLEDs achieve an improved performance, and the red OLED shows the best performance enhancement, with the luminance of 26 247 cd m−2, maximum current efficient of 30.7 cd A−1, and maximum external quantum efficiency of 17.4%. This provides a new strategy to achieve highly efficient ITOLEDs.

Detection of miR-155 Using Peptide Nucleic Acid at Physiological-like Conditions by Surface Plasmon Resonance and Bio-Field Effect Transistor.

MicroRNAs are small ribonucleotides that act as key gene regulators. Their altered expression is often associated with the onset and progression of several human diseases, including cancer. Given their potential use as biomarkers, there is a need to find detection methods for microRNAs suitable for use in clinical setting. Field-effect-transistor-based biosensors (bioFETs) appear to be valid tools to detect microRNAs, since they may reliably quantitate the specific binding between the immobilized probe and free target in solution through an easily detectable electrical signal. We have investigated the detection of human microRNA 155 (miR-155) using an innovative capturing probe constituted by a synthetic peptide nucleic acid (PNA), which has the advantage to form a duplex even at ionic strengths approaching the physiological conditions. With the aim to develop an optimized BioFET setup, the interaction kinetics between miR-155 and the chosen PNA was preliminarily investigated by using surface plasmon resonance (SPR). By exploiting both these results and our custom-made bioFET system, we were able to attain a low-cost, real-time, label-free and highly specific detection of miR-155 in the nano-molar range.

Construction of a Cu@hollow TS‐1 nanoreactor based on a hierarchical full‐spectrum solar light utilization strategy for photothermal synergistic artificial photosynthesis

AbstractThe artificial photosynthesis technology has been recognized as a promising solution for CO2 utilization. Photothermal catalysis has been proposed as a novel strategy to promote the efficiency of artificial photosynthesis by coupling both photochemistry and thermochemistry. However, strategies for maximizing the use of solar spectra with different frequencies in photothermal catalysis are urgently needed. Here, a hierarchical full‐spectrum solar light utilization strategy is proposed. Based on this strategy, a Cu@hollow titanium silicalite‐1 zeolite (TS‐1) nanoreactor with spatially separated photo/thermal catalytic sites is designed to realize high‐efficiency photothermal catalytic artificial photosynthesis. The space–time yield of alcohol products over the optimal catalyst reached 64.4 μmol g−1 h−1, with the selectivity of CH3CH2OH of 69.5%. This rationally designed hierarchical utilization strategy for solar light can be summarized as follows: (1) high‐energy ultraviolet light is utilized to drive the initial and difficult CO2 activation step on the TS‐1 shell; (2) visible light can induce the localized surface plasmon resonance effect on plasmonic Cu to generate hot electrons for H2O dissociation and subsequent reaction steps; and (3) low‐energy near‐infrared light is converted into heat by the simulated greenhouse effect by cavities to accelerate the carrier dynamics. This work provides some scientific and experimental bases for research on novel, highly efficient photothermal catalysts for artificial photosynthesis.

High FOM PCF-SPR refractive index sensor based on MgF2-Au double-layer films.

A simple twin-core D-shape photonic crystal fiber sensor based on surface plasmon resonance (SPR) is designed for the measurement of refractive indices (RI). The twin-core D-shape structure enhances the SPR effect, and the M g F 2-Au dual-layer film narrows the linewidth in the loss spectrum, consequently improving both the sensitivity and figure of merit (FOM). The properties of the sensor are analyzed by the finite element method. In the RI range of 1.32-1.42, the maximum wavelength sensitivity, FOM, and resolution are 62,000nm/RIU, 1281R I U -1, and 1.61×10-6, respectively.

Interface engineering enhanced g-C3N4/rGO/Pd composites synergetic localized surface plasmon resonance effect for boosting photocatalytic CO2 reduction

Interface engineering enhanced g-C3N4/rGO/Pd composites synergetic localized surface plasmon resonance effect for boosting photocatalytic CO2 reduction

Full-Spectrum Utilization of ZIF-67/Ag NPs/NaYF4:Yb,Er Photocatalysts for Efficient Degradation of Sulfadiazine: Upconversion Mechanism and DFT Calculation.

In this work, novel ternary composite ZIF-67/Ag NPs/NaYF4:Yb,Er is synthesized by solvothermal method. The photocatalytic activity of the composite is evaluated by sulfadiazine (SDZ) degradation under simulated sunlight. High elimination efficiency of the composite is 95.4% in 180min with good reusability and stability. The active species (h+, ·O2 - and ·OH) are identified. The attack sites and degradation process of SDZ are deeply investigated based on theoretical calculation and liquid chromatography-mass spectrometry analysis. The upconversion mechanism study shows that favorable photocatalytic effectiveness is attributed to the full utilization of sunlight through the energy transfer upconversion process and fluorescence resonance energy transfer. Additionally, the composite is endowed with outstanding light-absorbing qualities and effective photogenerated electron-hole pair separation thanks to the localized surface plasmon resonance effect of Ag nanoparticles. This work can motivate further design of novel photocatalysts with upconversion luminescence performance, which are applied to the removal of sulphonamide antibiotics in the environment.

Nanoparticles as Catalysts: Exploring Potential Applications

Abstract: Nanoparticles have emerged as highly promising catalysts due to their unique physical and chemical properties arising from their small size and high surface area–to–volume ratio. This review delves into the diverse applications of nanoparticles as catalysts in various chemical reactions. A key advantage lies in their substantial surface area–to–volume ratio, facilitation, enhanced accessibility of reactants, and heightened interaction with the catalyst surface. This distinctive characteristic results in improved catalytic activity and efficiency. Additionally, size-dependent properties, such as surface plasmon resonance and quantum confinement effects, offer opportunities for tailoring catalytic behavior. Despite their immense potential, challenges such as synthesis, stability, toxicity, aggregation, and recyclability require attention. Future research should prioritize scalable and sustainable synthesis methods, improve catalyst stability under harsh conditions, and ensure safe handling and disposal. This review provides an overview of the role of nanoparticles as catalysts and highlights their significance in various fields, highlighting their exceptional performance, versatility, and environmental benefits.