Surface Plasmon Resonance Effect Research Articles

Tuning sensitivity of surface plasmon resonance gas sensor based on multilayer black phosphorous

We investigated a gas sensor that makes use of the surface plasmon resonance (SPR) effect in a thick layer of gold (Au), copper (Cu), ZnO, and multilayer black phosphorous (BP). The suitability of the proposed gas sensor was investigated for a range of analyte gases recognized for their toxicity, greenhouse effect, or flammability. The proposed gas sensor obtains a maximum sensitivity of 258.77°/RIU with a remarkable full width at half maximum (FWHM) of 7.12°, detection accuracy (DA) of 0.14/°, and Figure of merit (FoM) of 36.22. The result of our enhanced numerical analysis indicates that the performance of a multilayer BP is enhanced when compared to a conventional gas sensor. As a result, using a SiO2 prism to sense different gases at a wavelength of 633[Formula: see text]nm, the suggested gas sensor may be more advantageous. Moreover, the maximum sensitivity of 374.31/RIU is obtained with a remarkable DA of 0.11° and FoM of 37.63/RIU to detect NO2 gas sensing to maintain the [Formula: see text]value. The gas sensor performance is high at different refractive indices for gas analyte (1–1.07). The performance of the proposed gas sensor is superior to that of the existing gas sensors.

High-sensitivity vector magnetic field sensor based on a V-shaped multimode-no-core-multimode fiber structure.

This work proposes and investigates a bent multimode-no-core-multimode optical fiber structure for vector magnetic field sensing applications. The bent no-core fiber (NCF) serves as the sensing area, and the gold film is deposited on its surface to excite the surface plasmon resonance effect. Due to the strong evanescent field of the unclad and bent NCF, the as-fabricated sensor exhibits a high sensitivity of 5630 nm/RIU in the refractive index range of 1.36-1.39. Magnetic fluid is employed as the magneto-sensitive material for magnetic field sensing, exhibiting a high magnetic field intensity sensitivity of 5.74 nm/mT and a high magnetic field direction sensitivity of 0.22 nm/°. The proposed sensor features a simple structure, low cost, point sensing, and excellent mechanical performance.

Design and simulation of a compact plasmonic photonic crystal fiber filter with wide band and high extinction ratio

In order to realize the performance optimization and function expansion of modern all-optical systems, this work presents a compact plasmonic photonic crystal fiber (PCF) filter, using finite element tool. The deposited gold and graphene layers within the elliptical pores interact with the transmitted light, creating surface plasmon resonance (SPR) effect that amplifies the energy difference between x- and y-polarized light greatly. The simulation results indicate that the structural parameters are configured with the cladding holes' diameter of 0.6 μm, the large-holes’ diameter of 1.2 μm, the inner small-holes’ diameter of 0.2 μm, the lattice constant of 2.0 μm, the elliptical holes' minor axis length of 0.45 μm, the elliptical holes' major axis length of 1.30 μm, the gold layer thickness of 50 nm, and the graphene layer thickness of 20 nm, the central wavelength of the proposed PCF filter is 1.56 μm. When the length of this PCF filter is 1 mm, a maximum extinction ratio (ER) of 133 dB, an operating bandwidth exceeding 800 nm, covering two common communication windows of 1.31 μm and 1.55 μm, as well as a low insertion loss (IL) of 0.59 dB can be achieved. What's more, the feasibility of fabricating the device is also examined. This filter with compactness, broadband and high-extinction demonstrates promising applications in optical communication, optical sensing, optical computing, and various other fields.

Multi-functional metasurface: ultra-wideband/multi-band absorption switching by adjusting guided-mode resonance and local surface plasmon resonance effects

This study introduces an innovative dual-tunable absorption film with the capability to switch between ultra-wideband and narrowband absorption. By manipulating the temperature, the film can achieve multi-band absorption within the 30–45 THz range or ultra-wideband absorption spanning 30–130 THz, with an absorption rate exceeding 0.9. Furthermore, the structural parameters of the absorption film are optimized using the particle swarm optimization (PSO) algorithm to ensure the optimal absorption response. The absorption response of the film is primarily attributed to the coupling of guided-mode resonance and local surface plasmon resonance effects. The film’s symmetric structure enables polarization incoherence and allows for tuning through various means such as doping/voltage, temperature and structural parameters. In the case of a multi-band absorption response, the film exhibits good sensitivity to refractive index changes in multiple absorption modes. Additionally, the absorption spectrum of the film remains effective even at large incidence angles, making it highly promising for applications in fields such as biosensing and infrared stealth.

Integration of Co Single Atoms and Ni Clusters on Defect-Rich ZrO2 for Strong Photothermal Coupling Boosts Photocatalytic CO2 Reduction.

We report a solvothermal method for the synthesis of an oxygen vacancy-enriched ZrO2 photocatalyst with Co single atoms and Ni clusters immobilized on the surface. This catalyst presents superior performance for the reduction of CO2 in H2O vapor, with a CO yield reaching 663.84 μmol g-1 h-1 and a selectivity of 99.52%. The total solar-to-chemical energy conversion efficiency is up to 0.372‰, which is among the highest reported values. The success, on one hand, depends on the Co single atoms and Ni clusters for both extended spectrum absorption and serving as dual-active centers for CO2 reduction and H2O dissociation, respectively; on the other hand, this is attributed to the enhanced photoelectric and thermal effect induced by concentrated solar irradiation. We demonstrate that an intermediate impurity state is formed by the hybridization of the d-orbital of single-atom Co with the molecular orbital of H2O, enabling visible-light-driven excitation over the catalyst. In addition, Ni clusters play a crucial role in altering the adsorption configuration of CO2, with the localized surface plasmon resonance effect enhancing the activation and dissociation of CO2 induced by visible-near-infrared light. This study provides valuable insights into the synergistic effect of the dual cocatalyst toward both efficient photothermal coupling and surface redox reactions for solar CO2 reduction.

Localized surface-plasmon resonance effect as a new driver of Z-scheme electron transfer in cerium dioxide–graphitic carbon nitride heterojunctions

The intersecting interface between the two semiconductors of cerium dioxide (CeO2)–graphitic carbon nitride (g-C3N4) heterojunctions, which have demonstrated excellent photocatalytic activity, inhibits the rapid compounding of the photogenerated electron–hole pairs of g-C3N4. CeO2–g-C3N4 heterojunctions with Z-scheme and type-II electron-transfer routes were prepared via calcination in argon and air atmospheres, respectively. The built-in electric field theory cannot be used to explain the presence of a type-II electron-transfer route in CeO2–g-C3N4 heterojunctions. According the femtosecond transient absorption spectra, the localized surface-plasmon resonance (LSPR) effect of CeO2 drove the Z-scheme electron transfer in CeO2–g-C3N4 heterojunctions. The CeO2–g-C3N4 heterojunction exhibited a type-II electron-transfer route when the particle size of CeO2 increased, which attenuated the LSPR effect. The CeO2–g-C3N4 heterojunction with the Z-scheme electron-transfer route exhibited 4.4 times higher degradation efficiency for bamboo pulping wastewater than g-C3N4, and this result was attributed to the reduced complexation of photogenerated electron–hole pairs and extended photogenerated electron lifetime. Overall, this research provides a new idea for constructing Z-scheme electron-transfer heterojunctions.

Efficient gold recovery from low concentrated Au(S2O3)23− solution through enhanced photocatalysis via photothermal and surface plasmon resonance assistance on MoS2/MXene/Ag

Thiosulfate technique is the most promising method to recover gold from electronic waste (e-waste) and natural ores due to its non-toxicity and high leaching efficiency. However, the bad affinity between Au(S2O3)23− and traditional adsorbents leads to unsatisfied gold recovery performance from leaching solution. In this work, highly efficient recovery of gold from low concentrated Au(S2O3)23− solution was achieved through enhanced photocatalysis process on a novel MoS2/MXene/Ag adsorbent. During recovery procedure, Au(S2O3)23− was in-situ reduced to Au0 by photogenerated electrons and then anchored on MoS2/MXene/Ag. Under Au(S2O3)23− concentration <10 ppm, over 99 % gold recovery performance could achieve within 2 h. Experimental tests have proved that MXene made fully use of near infrared (NIR) light energy to exhibit better photothermal effect, and surface plasmon resonance (SPR) effect of Ag can simultaneously facilitate the separation of electron-hole pairs on MoS2. By means of external temperature input and rapid charge carrier transmission, plenty of electrons were excited from MoS2/MXene/Ag for Au(S2O3)23− recovery. This work paved a pathway for efficient Au(S2O3)23− recovery, which catered to the demand for green production of gold in the future.

Surface plasmon enhancement of 1D Ag nanowires modified electro-treated BiVO4 photoanode with abundant oxygen vacancies for solar water oxidation

The high carrier complexation rate is still one of the main obstacles for bismuth vanadate (BiVO4) to be used in photoelectrochemical (PEC) water oxidation. In this work, we used a simple method for dropping one dimension (1D) silver nanowires (Ag NWs) on the surface of electro-treated BiVO4 (Ag NWs/E-BiVO4). The photocurrent of Ag NWs/E-BiVO4 under AM 1.5 G illumination reaches to 3.12 mA/cm2 which is about 6.2 times than the pure BiVO4 photoelectrode. Meanwhile, the photogenerated charges injection efficiency of Ag NWs/E-BiVO4 photoelectrodes increasing from 12.7 % to 77.5 % than the pure BiVO4 photoelectrode. This is because the surface plasmon resonance (SPR) effect of 1D Ag nanowires enhanced the visible light absorption and provide more Ag active sites. Furthermore, the density functional theory (DFT) calculations show that the Ag NWs/E-BiVO4 have the best adsorption capacity for OH– and the electro-treated BiVO4 with rich oxygen vacancies greatly improves the electron transport efficiency which is benefit for improving the PEC catalytic performance. Thus, this work provides a simple method to enhance the PEC water splitting performance of BiVO4.

Synthesis of Structure-Adjustable R-Au/Pt-CdS Nanohybrids with Strong Plasmon Coupling and Improved Photothermal Conversion Performance.

Noble metal nanomaterials with a localized surface plasmon resonance effect exhibit outstanding advantages in areas such as photothermal therapy and photocatalysis. As a unique plasmonic metal nanostructure, gold nanobipyramids have been attracting much interest due to their strong specific local electric field intensity, large optical cross sections, and high refractive index sensitivity. In this study, we propose a novel three-component hetero-nanostructure composed of rough gold nanobipyramids (R-Au NBPs), Pt, and CdS. Initially, purified gold nanobipyramids are regrown to form R-Au NBPs that have a certain degree of roughness. These R-Au NBP substrates with a rough surface provide more hotspots and strengthen the intensity of localized electric fields. Subsequently, Pt and CdS nanoparticles are selectively deposited onto the surface of R-Au NBPs. Pt nanoparticles can provide more active sites. Each component of this hetero-nanostructure directly contacts others, creating multiple electron transfer channels. This novel design allows for tunable localized plasmon resonance wavelengths ranging from the visible to near-infrared regions. These factors contribute to the final superior photothermal conversion performance of the R-Au/Pt-CdS nanohybrids. Under the irradiation of near-infrared light (1064 nm), the photothermal conversion efficiency of R-Au/Pt-CdS reached 38.88%, which is 4.49, 1.5, and 1.22 times higher than that of Au NBPs, R-Au NBPs, and R-Au NBPs/Pt, respectively.

Constructing interface chemical coupling S-scheme heterojunction MoO3-x@PPy for enhancing photocatalytic oxidative desulfurization performance: Adjusting LSPR effect via oxygen vacancy engineering

Construction of photocatalyst that combines excellent electron transfer and photoresponse capabilities to enhance photocatalytic performance remains a challenging task. In this work, interfacial Mo-N bonds and vacancy engineering collaborative modified MoO3-x@polypyrrole (MP) S-scheme heterojunction is rational designed for efficient photocatalytic oxidative desulfurization. The addition of polypyrrole introduces rich defects which inducing the localized surface plasmon resonance (LSPR) effect and enhancing light absorption. Furthermore, the combination facilitates the formation of Mo-N bonds. The modifications amplify the built-in electric field and conduct the efficacious separation of photogenerated carriers. With the synergism of LSPR effect and interfacial chemical Mo-N bonds, the optimal MP photocatalyst displays attractive desulfurization rate of 100% for dibenzothiophene (DBT) in 60 min under illumination, touching the objective of ultra-deep desulfurization. The study extends a novel understanding of the impact of LSPR effect and heterojunction interface charge transfer on the photocatalytic desulfurization ability.

High-efficient water splitting over an in-situ growth novel electrocatalyst of metal-organic framework-based nanostructures

Metal-organic frameworks (MOFs) as emerging material have drawn much attention to apply to the field of water splitting. In this paper, layered NiFe-MIL-53 and nanoflower-like CoFe-MOF-74 were sequentially grown on nickel foam through two-step in-situ growth to construct a MOF-74/MIL-53 heterojunction. On this basis, we used the localized surface plasmon resonance (LSPR) effect of gold nanoparticles (Au NPs) to significantly improve the oxygen evolution reaction performance of MOF-74/MIL-53 heterojunction. Under illumation, the obtained Au-MOF-74/MIL-53 exhibits a lower overpotential of 218 mV, which is far superior to commercial catalyst. The reaction kinetics are significantly enhanced due to the lower charge transfer resistance and the higher electric double layer capacitance. We confirmed the existence of charge transfer between Au NPs and MOFs, and at the same time, the deposition of Au NPs significantly reduced the charge transfer resistance of MOF-74/MIL-53. On the basis of our work, we provide a novel MOF-based electrocatalytic nanocomposite structure for efficient water splitting.

TiO2 nanotubes modification by photodeposition with noble metals: Characterization, optimization, photocatalytic activity, and by-products analysis

Self-organized TiO2 nanotubes (TNTs) with 4 µm length were obtained by anodization method and calcined to obtain anatase crystallite phase. The photocatalysts were further decorated with Au, Ag, Pt or Pd nanoparticles (NPs), varying the metal loads (0.50, 0.75, 1, 2 and 5 mol%) by photodeposition. The material characterization confirmed the presence of nanoparticles in the TNTs surface, signs of the localized surface plasmon resonance (LSPR) effect for some samples and a bandgap energy of 3.1–3.2 eV. Photoluminescence measurements also confirmed that most of the samples with metallic nanoparticles had the recombination of photogenerated carriers lowered due to the trapping effect of the deposited metal NPs. The photoactivity was evaluated by phenol degradation using UV-Vis or visible radiation. Under UV-Vis, the best samples (2 and 5 mol% of Au-TNTs and 0.75, 1, and 2 mol% of Pd-TNTs) led to 97% phenol removal in 60 min while pristine TNTs reached 92% removal. Under visible radiation, the pristine and the Au-TNTs led to about 3% removal, with the best sample being 2 mol% Pd-TNTs with 14% removal in 60 min. Similar results were obtained for 1 and 5 mol% Pd-TNTs (12% and 13% of phenol removal, respectively). The by-products analysis suggest different degradation mechanisms and it is observed different kinetic rates for different metal types, metal loads or types of radiation.

High-Efficiency Ag-Modified ZnO/g-C3N4 Photocatalyst with 1D-0D-2D Morphology for Methylene Blue Degradation.

Photocatalysts with different molar ratios of Ag-modified ZnO to g-C3N4 were prepared through an electrostatic self-assembly method and characterized through techniques such as X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. The resulting Ag-ZnO/g-C3N4 photocatalysts exhibited a unique 1D-0D-2D morphology and Z-type heterojunction. Moreover, g-C3N4 nanosheets with large layer spacing were prepared using acid treatment and thermal stripping methods. The Z-type heterostructure and localized surface plasmon resonance effect of Ag nanowires enabled high-speed electron transfer between the materials, while retaining large amounts of active substances, and broadened the light response range. Because of these features, the response current of the materials improved, and their impedance and photoluminescence reduced. Among the synthesized photocatalysts, 0.05Ag-ZnO/g-C3N4 (molar ratio of g-C3N4/ZnO: 0.05) exhibited the highest photocatalytic performance under UV-visible light. It degraded 98% of methylene blue in just 30 min, outperforming both g-C3N4 (21% degradation in 30 min) and Ag-ZnO (84% degradation in 30 min). In addition, 0.05Ag-ZnO/g-C3N4 demonstrated high cycling stability.

Tandem Electric-Fields Prolong Energetic Hot Electrons Lifetime for Ultra-Fast and Stable NO2 Detection.

Prolonging energetic hot electrons lifetimes and surface activity in the reactive site can overcome the slow kinetics and unfavorable thermodynamics of photo-activated gas sensors. However, bulk and surface recombination limit the simultaneous optimization of both kinetics and thermodynamics. Here tandem electric fields are deployed at (111)/(100)Au-CeO2 to ensure a sufficient driving force for carrier transfer and elucidate the mechanism of the relationship between charge transport and gas-sensing performance. The asymmetric structure of the (111)/(100)CeO2 facet junction provides interior electric fields, which facilitates electron transfer from the (100)face to the (111)face. This separation of reduction and oxidation reaction sites across different crystal faces helps inhibit surface recombination. The increased electron concentration at the (111)face intensifies the interface electric field, which promotes electron transfer to the Au site. The local electric field generated by the surface plasmon resonance effect promotes the generation of high-energy energy hot-electrons, which maintains charge concentration in the interface field by injecting into (111)/(100)CeO2, thereby provide thermodynamic contributions and inhibit bulk recombination. The tandem electric fields enable the (111)/(100)Au-CeO2 to rapidly detect 5ppm of NO2 at room temperature with stability maintained within 20s.

Inclusion of metal nanoparticles at the core-shell interface of GaAs0.99Bi0.01/ZnO/ITO core-shell nanowire solar cell for photovoltaic performance enhancement

Optoelectronic performance analysis of perpendicularly aligned conformally coated GaAs0.99Bi0.01/ZnO/ITO core–shell nanowire solar cell having a core length of 1 μm, core diameter of 160 nm, shell thickness of 10 nm and period of 280 nm, decorated with Au metal nanoparticles(MNPs) of variable diameters at the core–shell interface is done employing FDTD method. Diameter optimization of MNPs with four different diameters values around core GaAs0.99Bi0.01 nanowire is accomplished in terms of maximum short circuit current density (Jsc), which offered an optimized diameter combination of D1 = D2 = 50 nm and D3 = 34 nm, D4 = 10 nm, resulting in a maximum Jsc of 32.6 mA cm−2. A detailed analysis of the electric field profile including its top view and longitudinal view is presented to investigate the distribution of electric field upon optical illumination at different wavelength range. The overall photo generation rate profile is also presented to focus on the localized surface plasmon resonance effect caused by the metal nanoparticles (MNPs). In order to boost the electrical performance, a thin coating of electron selective ZnO shell is used around p type GaAs0.99Bi0.01core, which aids in charge carrier separation, thereby improving open circuit voltage (Voc) and overall power conversion efficiency (PCE). The electrical characteristics of bare NW and MNP decorated GaAs0.99Bi0.01/ZnO core–shell nanowire solar cell for different MNP diameters have been compared. For the optimized diameter combination, as stated above, a Voc of 941 mV, Jsc of 28 mA cm−2, FF of 84.35% and PCE of 22.19% is obtained for SRV of 105 cm s−1 at the interfaces and SRH recombination lifetime as less as 10 ns. For SRV of 105 cm s−1 at the interfaces and SRH recombination lifetime of 1 μs, this proposed structure can achieve a Voc of 1.06 V, Jsc of 31.5 mA cm−2, PCE of 29.37% and FF of 87.88% for equal diameters of D1 = D2 = D3 = D4 = 50 nm.

Constructed of Cd-based organic framework heterostructure material for solar-powered organic dye purification

A novel water-stable Cd-based organic framework material (Cd-MOF) has been synthesized based on the 4,4′-([2,2′-bipyridine]-6,6′-diylbis(oxy))phthalic acid (H4L) ligand and Cadmium nitrate tetrahydrate (Cd(NO3)2·4H2O) with a solvothermal method. We also prove that the rational design and preparation of Cd-MOF\\Ag heterojunctions by depositing Ag nanoparticles on the surface of Cd-MOF is an effective photocatalyst for the degradation of organic dyes in water. The photodegradation rates of RhB and MO were significantly improved under simulated sunlight conditions (AM1.5G), which reaching 0.68 and 1.549 min−1 g−1, respectively. The prominent performance is attributed to the efficient separation of photo-generated electrons and holes caused by the composite heterojunction of Cd-MOF/Ag. The surface plasmonic resonance (SPR) effect of Ag nanoparticles and the Schottky junction between Ag and Cd-MOF play crucial role in the photocatalytic degradation process. This work provides a new strategy for preparing photocatalysts and promoting the development of the degradation of organic dye pollutants in effluent with MOF-based material as photocatalysts.

Construction of Au quantum dots/nitrogen-defect-enriched graphite carbon nitride heterostructure via photo-deposition towards enhanced nitric oxide photooxidation

The challenge of mitigating pollution stemming from industrial exhaust emissions is a pressing issue in both academia and industry. This study presents the successful synthesis of nitrogen-defect-enriched graphite carbon nitride (g-C3N4) using a two-step calcination technique. Furthermore, a g-C3N4-Au heterostructure was fabricated through the photo-deposited Au quantum dots (QDs). When subjected to visible light irradiation, this heterostructure exhibited robust nitric oxide (NO) photooxidation activity and stability. With its fluffy, porous structure and large surface area, the nitrogen-defect-enriched g-C3N4 provides more active sites for photooxidation processes. The ability of g-C3N4 to absorb visible light is enhanced by the local surface plasmon resonance (LSPR) effect of Au QDs. Additionally, the lifetime of photogenerated charge carriers is extended by the presence of N defects and Au, which effectively prevent photogenerated electron-hole pairs from recombining during the photooxidation process. Moreover, the oxidation pathway of NO was analyzed through In-situ Fourier transform infrared (FT-IR) spectroscopy and Density Functional Theory (DFT) calculation. Computational findings revealed that the introduction of Au QDs decreases the activation energy of the oxidation reaction, thereby facilitating its occurrence while diminishing the formation of intermediate products. As a result, NO is predominantly converted to nitrate (NO3−). This work unveils a novel approach to constructing semiconductor-cocatalyst heterostructures and elucidates their role in NO photooxidation.

Nickel-doped silver nanoclusters as a mechanism to capture photons

Narrow width of optical absorption of conducting polymers and photons energy losses have been the challenges for fabricating highly efficient thin-film organic solar cell. Nickel-doped silver nanoclusters (Ni/Ag NCs) are employed here to capture more photons using polymers blend solar absorber medium to improve solar cell performances. The poly-3-hexylthiophene and (6-6)phenyl-C61-butyric acid methyl ester molecules blend were used a solar absorber layer in this investigation. The solar cells fabricated with NCs exhibited enhanced opt-electronic properties compared to the reference solar cell. Consequently, the experimental results suggest that the power conversion efficiency (PCE) has substantially increased with the incorporations of NCs in absorber layer, which is dependent on the concentrations of NCs in the medium. The maximum PCE achieved, in this work, is η\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\eta $$\\end{document} = 6.2% at 2% of NCs by weight, which has exhibited to the lowest energy losses compared to other doping levels. This improvement in PCE is attributed to the occurrence of local surface plasmon resonance effect due to the inclusion of Ni/Ag NCs in polymer matrix. The results provide valuable insights on the use of Ni/Ag NCs for efficient photons capture in thin-film polymers blend medium.

Precise regulation of surface plasmonic hotspots in an Au split nanoring coupled system

The signal enhancement in plasmon-enhanced spectroscopy is primarily contributed by hotspots generated through the surface plasmon resonance effect. Precise control of hotspot positions within nanostructures is of great significance in surface-enhanced Raman spectroscopy (SERS) and high spatial resolution imaging. However, predicting the positions of hotspots is challenging due to the small nanogaps and complex plasmonic interactions. In this study, we theoretically investigate the localized surface plasmonic properties of split ring nanostructure. The effects of variations in the inner radius, gap distance and thickness of the split ring on the hotspot distribution at the nanogaps are systematically analyzed using a three-dimensional finite element method. The results demonstrate that precise control over the positions and quantities of hotspots can be achieved by choosing the excitation wavelength and the gap size of the split rings. The calculated maximum Raman enhancement obtained at the hotspots can reach nine orders of magnitude. Our findings not only contribute to a deeper understanding of the SERS enhancement mechanism, but also provide theoretical insights for further development of surface-enhanced fluorescence, plasmonic sensors, and super-resolution imaging in the field of interface spectroscopy.

Interface interaction mediated surface plasmon resonance enhancement promoted visible-light-driven CO2 reduction with water

The conversion of carbon dioxide (CO2) into fuel using solar energy holds significant promise. However, the inefficient use of light and poor production activity have hindered its development. Here, we propose a simple in situ annealing oxidation method by coating a layer of TiO2 outside TiN, a material with a favorable price and localized surface plasmon resonance (LSPR) effect, to create an L-TiNO composite. The yield of CO over L-TiNO (50.8 μmol g−1 h−1) is 56.4 times that over TiO2 (0.9 μmol g−1 h−1) under visible light irradiation in pure aqueous environment, with a selectivity of 95.98%. In-situ Fourier transform infrared (FTIR) measurements reflect the CO2-COOH*-CO conversion route happening on L-TiNO. Characterizations like the Kelvin probe force microscopy (KPFM) technique confirm the generation of built-in electric field, which facilitates efficient carrier separation and migration. Density functional theory (DFT) calculations support that L-TiNO with LSPR effect alters the shape of absorbed CO2 to facilitate generation COOH* via forming hydroxyl end group (Ti-OH) and promotes CO* desorption to CO(g). This work provides valuable insights into the coupling of plasmonic materials with semiconductors to achieve efficient solar energy utilization.