KR102628343B1 - PREPARING METHOD OF Ag NANOPRISM HAVING IMPROVED CHEMICAL STABILITY, Ag NANOPRISM PREPARED THEREBY, AND IODINE ION SENSOR COMPRISING THE SAME - Google Patents

Abstract

The present invention includes the steps of (a) synthesizing silver (Ag) nanoprisms, and (b) adding and stirring tetramethylethylenediamine (TEMEA) to the silver (Ag) nanoprism aqueous dispersion to produce silver (Ag) nanoprisms. Method for producing silver (Ag) nanoprisms with improved chemical stability, comprising capping the prism particle surface with tetramethylethylenediamine (TEMEA), silver (Ag nanoprisms produced thereby, and including the same) According to the present invention, the surface of a silver (Ag) nanoprism is formed with tetramethylethylenediamine (TEMEA) through a simple room temperature single process that takes less than 10 minutes based on water, an eco-friendly solvent. By passivation, silver (Ag) nanoprisms with significantly improved chemical stability can be manufactured without changing optical properties such as localized surface plasmon resonance (LSPR) characteristics.

Description

Method for manufacturing silver (Ag) nanoprisms with improved chemical stability, silver (Ag) nanoprisms produced thereby, and iodine ion sensors containing the same {PREPARING METHOD OF Ag NANOPRISM HAVING IMPROVED CHEMICAL STABILITY, Ag NANOPRISM PREPARED THEREBY, AND IODINE ION SENSOR COMPRISING THE SAME}

The present invention relates to a method for manufacturing silver (Ag) nanoprisms surface-treated to improve chemical stability, silver (Ag) nanoprisms produced thereby, and iodine ion sensors containing the same.

Silver (Ag) nanoprism material is a material with excellent localized surface plasmon resonance (LSPR) properties, and is attracting attention as a material that can cause very colorful changes according to changes in shape. .

As described above, silver (Ag) nanoprism materials have excellent optical properties, but have the disadvantage of poor chemical stability due to structural weaknesses including sharp edges.

Accordingly, in the prior art, a method of forming a thin film of metal or metal oxide material was mainly used to improve the chemical stability of silver (Ag) nanoprisms. This method changes the optical properties of silver (Ag) nanoprisms. There is a problem.

Therefore, there is a need for the development of technology that can improve the chemical stability of silver (Ag) nanoprisms without changing or deteriorating their optical properties.

Chinese published patent CN 106423291 A (Publication date: 2017.02.22)

The technical problem to be solved by the present invention is to have significantly improved chemical stability compared to the prior art without changing or weakening the optical properties, and at the same time having selective etching properties only for specific ions (I ^- ), so as to provide a detection probe material for that ion. The present invention provides a method for manufacturing a silver (Ag) nanoprism that can be used as a silver (Ag) nanoprism, a silver (Ag) nanoprism manufactured thereby, and an iodine ion sensor containing the same.

In order to achieve the above technical problem, the present invention includes the steps of (a) synthesizing silver (Ag) nanoprisms, and (b) adding tetramethylethylenediamine (TEMEA) to an aqueous dispersion of silver (Ag) nanoprisms. We propose a method for manufacturing silver (Ag) nanoprisms with improved chemical stability, which includes the step of stirring and capping the surface of the silver (Ag) nanoprism particles with tetramethylethylenediamine (TEMEA).

At this time, in the silver (Ag) nanoprism synthesis step according to step (a), silver precursors such as silver nitrate (AgNO ₃ ), polyvinylpyrrolidone (PVP), polyacrylamide (PAM), and aceto Silver nanoprisms can be synthesized by reducing the silver precursor in an aqueous mixture containing nitrile (acetonitrile).

In another aspect, the present invention proposes a silver (Ag) nanoprism manufactured according to the above-described manufacturing method and having excellent chemical stability by modifying the surface with tetramethylethylenediamine (TEMEA).

Furthermore, in another aspect of the invention, the present invention proposes a colorimetric sensor for detecting iodine ions including silver nanoprism particles whose surface is modified with tetramethylethylenediamine (TEMEA) and water.

At this time, the silver nanoprism particles included in the colorimetric sensor for detecting iodine ions are etched into a spherical or oval shape by iodine ions (I ^- ).

In addition, the colorimetric sensor for detecting iodine ions is characterized in that the color changes from gray to cyan, blue, purple, or pink by adding iodine ions.

According to the present invention, the surface of the silver (Ag) nanoprism is passivated with tetramethylethylenediamine (TEMEA) through a simple room temperature single process that takes less than 10 minutes based on water, an eco-friendly solvent, Silver (Ag) nanoprisms with significantly improved chemical stability can be manufactured without changing optical properties such as surface plasmon resonance (LSPR) characteristics.

In addition, the silver (Ag) nanoprisms manufactured according to the present invention are not etched and are very stable even when exposed to strong etching agents such as hydrogen peroxide (H ₂ O ₂ ), bromine ions (Br ^- ), and chlorine ions (Cl ^- ). On the other hand, because it is selectively etched only for iodine ions (I ^- ) and changes its shape, causing a color change in the silver (Ag) nanoprism aqueous solution, it is complicated, unlike the existing method of detecting iodine in an aqueous solution. It can be very useful as an optical sensor material that can detect iodine ions with high accuracy with the naked eye very quickly in the field without using sophisticated equipment.

Figures 1(a) and 1(b) respectively show aqueous Ag nanoprism colloids exposed to 2.2mM sodium 4-vinylbenzenesulfonate (Na-SS) for various times from 10 minutes up to 60 minutes. Photographs and extinction spectra of aqueous Ag nanoprism colloidal dispersions, and Figures 1(c) to 1(f) show Ag exposed to 2.2mM Na-SS at room temperature for 0, 10, 30, and 60 minutes, respectively. This is a TEM image of a nanoprism.
Figures 2(a) and 2(b) are photographs and extinction spectra of TEMEA-treated Ag nanoprism aqueous dispersions exposed to 2.2mM Na-SS for various times from 10 min up to 60 min, respectively, and Figure 2(c) and Figure 2(d) are TEM images of TEMEA-treated Ag nanoprisms exposed to 2.2mM Na-SS for 30 and 60 minutes, respectively.
Figure 3 shows pure Ag nanoprisms and TEMEA-treated Ag nanoprisms exposed to different strong etchants [(a) NaBr, (b) NaCl, (c) Na-PSS, (d) H ₂ O ₂ ] for 1 hour. This is a photo of the prism and the extinction spectrum showing changes in LSPR characteristics.
Figures 4(a) and 4(b) are photographs and extinction spectra of Ag nanoprism aqueous dispersions exposed to 0.02mM NaI for various times from 10 minutes up to 60 minutes, and Figures 4(c) and 4(d), respectively. ) are TEM images of Ag nanoprisms exposed to 0.02mM NaI for 30 and 60 minutes, respectively.
Figures 5(a) and 5(b) are photographs and extinction spectra, respectively, of TEMEA-treated Ag nanoprism aqueous dispersions in 0.02mM NaI for various times from 10 min up to 60 min, and Figure 5(c) is I at room temperature. ^- is a TEM image of the TEMEA-treated Ag nanoprism in the absence of -, and Figures 5(d) to 5(f) are TEMEA-treated Ag nanoprisms exposed to I ^- for 10 minutes, 30 minutes, and 60 minutes, respectively, at room temperature. This is a TEM image.
Figures 6(a) and 6(b) are photographs and extinction spectra showing changes in LSPR characteristics of TEMEA-treated Ag nanoprism colloidal dispersions exposed to various concentrations of NaI for 20 minutes at room temperature, respectively, and Figure 6(c) is is a plot of wavelength shift (Δλ) versus I ^- concentration prepared using the extinction spectrum data in Figure 6(b).
Figure 7(a) is the UV/Vis/NIR extinction spectrum of TEMEA-treated Ag nanoprism colloidal dispersions exposed to 20 μM I ^- or 100 μM of various halide ions or heavy metal ions for 60 min at room temperature. Figure 7(b) is a plot of the wavelength shift (Δλ) values observed in Figure 7(a) (the interpolation shows TEMEA-treated Ag nanoscale samples exposed to 20 μM I ^- or 100 μM of various halide ions or heavy metal ions). This is a photo of a prismatic colloidal dispersion).
8(a) and 8(b) are TEMEA-treated Ag nanoprism colloidal dispersions obtained using kelp and tap water, respectively, after exposure to real samples with various I ^- concentrations indicated and aging for 20 minutes at room temperature. is a photograph and extinction spectrum, and Figure 8(c) is a plot of the wavelength shift (Δλ) versus I ^- concentration prepared using the extinction spectrum data in Figure 8(b).
Figure 9 is a plot of the wavelength shift (Δλ) versus I ^- concentration for the sample containing deionized water and NaI and the sample containing tap water and kelp in Figures 6(c) and Figure 8(c), respectively.

In describing the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description will be omitted.

Since embodiments according to the concept of the present invention can make various changes and have various forms, specific embodiments will be illustrated in the drawings and described in detail in the present specification or application. However, this is not intended to limit the embodiments according to the concept of the present invention to a specific disclosed form, and should be understood to include all changes, equivalents, and substitutes included in the spirit and technical scope of the present invention.

The terms used in this specification are merely used to describe specific embodiments and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as “include” or “have” are intended to indicate the existence of a described feature, number, step, operation, component, part, or combination thereof, but are not intended to indicate the presence of one or more other features or numbers. It should be understood that this does not preclude the existence or addition of steps, operations, components, parts, or combinations thereof.

Hereinafter, the present invention will be described in more detail through examples.

Embodiments according to the present specification may be modified into various other forms, and the scope of the present specification is not to be construed as being limited to the embodiments described in detail below. The embodiments of this specification are provided to more completely explain the present specification to those with average knowledge in the art.

<Example>

1. Synthesis of Ag nanoprisms

0.1 g of 5% by weight polyacrylamide (PAM) aqueous solution and 1.870 g of polyvinylpyrrolidone (PVP) were placed in a 20 mL vial containing 8 mL of deionized water (DI water) and stirred uniformly through magnetic stirring. Subsequently, 2 mL of 282 mM silver nitrate (AgNO ₃ ) aqueous solution and 1 mL of acetonitrile were sequentially added to the vial, and the resulting mixture was heated at 80°C for 24 hours while magnetically stirring. The heated stirred mixture was centrifuged at 13,000 rpm for 10 minutes, and the resulting final product was washed three times with deionized water to remove PVP and solvent.

2. Characterization analysis and chemical stability consideration of Ag nanoprisms

Ag nanoprisms were synthesized using a one-step water-based chemical reduction method using polyvinylpyrrolidone (PVP), a non-toxic water-soluble polymer, as a reducing agent. The aqueous colloidal dispersion of the synthesized Ag nanoprisms was gray, as shown in the leftmost vial in Figure 1(a), and the average edge length of the Ag nanoprisms was measured to be about 78 (± 8.6) nm (Figure 1(a). see c)). The UV/Vis/NIR extinction spectrum obtained from the aqueous Ag nanoprism colloidal dispersion showed a strong peak at approximately 830 nm (Figure 1(b)), which was attributed to the in-plane dipole LSPR band of the Ag nanoprism. .

Sodium 4-vinylbenzenesulfonate (Na-SS) is a highly reactive vinyl monomer containing a hydrophilic sulfonate group and is converted into sodium polystyrenesulfonate (Na-PSS) through free radicals and controlled radical polymerization. It has been used as a starting material to synthesize and has low toxicity and high thermal stability. Ag nanoprisms prepared by the synthesis method described in this example were found to be very vulnerable to chemical etching by Na-SS. The aqueous dispersion of Ag nanoprisms showed a dramatic color change within 60 minutes when 2.2mM Na-SS (Na-SS/Ag molar ratio ∼ 5.0) was added, as shown in Figure 1(a). The UV/Vis/NIR spectrum of the Ag nanoprism dispersion exposed to 2.2mM Na-SS for increased periods showed a continuous blue shift of the in-plane dipole LSPR peak (Figure 1(b)). Because it was found that changes in LSPR properties of Ag nanostructures were closely related to changes in particle size and shape, in this example, images of Ag nanoprisms exposed to Na-SS were obtained and TEM analysis was performed. As shown in Figures 1(c) to 1(f), Ag nanoprisms exposed to Na-SS for more time gradually became smaller and their sharp edges gradually became dull. At an exposure time of 60 minutes, the Ag nanoprisms were transformed into elliptical Ag nanostructures. Therefore, the change in LSPR characteristics according to Figure 1(b) appears to be related to the change in size and shape of Ag nanoprisms due to chemical etching by Na-SS. From the above results, it was confirmed that the Ag nanoprisms obtained in this example were vulnerable to chemical etching by Na-SS and were easily damaged when exposed to these chemicals.

3. Chemical passivation of Ag nanoprisms using TEMEA

N,N,N′,N′-tetramethylethylenediamine ( N,N,N′,N′ -tetramethylethylenediamine, TEMEA) was used as a ligand for metal ions. Although the interaction between Ag nanocrystals and TEMEA has not yet been studied in detail, the present inventors believe that TEMEA, functioning as an organic ligand, may be very effective in overcoming the inherent instability of Ag nanoprisms by passivating the surface of Ag nanoprisms. It was found that it can be done. To investigate the effect of TEMEA as an organic ligand on the stability of Ag nanoprisms, TEMEA was introduced into an aqueous dispersion of Ag nanoprisms and stirred and aged at room temperature for 5 minutes. The final concentration of added TEMEA was set to 5 mM (TEMEA/Ag molar ratio ~ 11.4). The TEMEA-treated Ag nanoprism colloidal dispersion showed no color change for 24 hours under ambient conditions, and the UV/Vis/NIR extinction spectrum barely changed during that period. The lack of substantial change in the intrinsic LSPR properties of Ag nanoprisms upon introduction of TEMEA indicates that TEMEA treatment neither affected the dispersion stability of Ag nanoprisms nor damaged them. To demonstrate that TEMEA actually caps the surface of Ag nanoprisms, TGA analysis was performed on the nanoprisms and the results showed that TEMEA-treated Ag nanoprisms contained more organic compounds than non-TEMEA-treated Ag nanoprisms. It was confirmed that it contains

Additionally, elemental analysis performed using It was shown that it covers the surface of

Referring to Figure 2(a), TEMEA-treated Ag nanoprism dispersions exposed to 2.2mM Na-SS for different times showed no color change during exposure up to 60 minutes. These results were completely different from the dramatic color change of the Ag nanoprism aqueous solution without TEMEA, as shown in Figure 1(a). Figure 2(b) shows the UV/Vis/NIR extinction spectrum of the TEMEA-treated Ag nanoprism dispersion, and the spectral analysis shows that there is little change in LSPR characteristics due to the addition of NaSS even after 60 minutes of exposure. TEM images of TEMEA-treated Ag nanoprisms exposed to NaSS for 30 and 60 min are shown in Figures 2(c) and 2(d). Examination of these images confirmed that the TEMEA-treated Ag nanoprisms maintained their triangular shape with sharp edges during 60 minutes of exposure to NaSS. These results clearly showed that simple treatment of Ag nanoprisms with TEMEA in aqueous solution could protect the nanoprisms from being chemically etched by Na-SS.

To demonstrate the robustness of the surface passivation of Ag nanoprisms induced by TEMEA, halide ions (Br ^- and Cl ^- ) and polyelectrolyte (sodium) were used as other strong etchants that can chemically etch Ag nanoprisms within a short time. Tests were conducted using -polystyrenesulfonate (Na-PSS)) and a strong oxidizing agent (H ₂ O ₂ ). In each experiment using the above etchant, the concentration of TEMEA was set to 5 mM (TEMEA/Ag molar ratio ~ 11.4), but because the etching power of each etchant was different, the concentration of the etchant was different. In our previous research, Ag nanoprisms were found to be particularly vulnerable to Br ^- than to other halide ions. As shown in Figure 3(a), the aqueous dispersion of Ag nanoprisms exposed to NaBr (final concentration of NaBr ~ 0.5mM) at room temperature turns orange within 60 min, consistent with the LSPR results of the corresponding UV/Vis/NIR extinction spectra. This shows that when the Ag nanoprism dispersed sample is exposed to NaBr for 60 minutes, a blue shift exceeding 330 nm occurs in the in-plane dipole resonance peak of the Ag nanoprism. However, color change due to Br ^- was not observed in the Ag nanoprism sample treated with TEMEA (see Figure 3(a)). In another test, aqueous Ag nanoprisms were exposed to NaCl (final concentration of NaCl ~ 200mM) and Na-PSS (final concentration of Na-PSS ~ 20mM (calculated based on repeat units of Na-PSS)) for 60 min each. The dispersion changed from gray to blue and pink, respectively, and the wavelength shift (Δλ) values of the in-plane dipole LSPR mode were found to be approximately 240 and 300 nm, respectively (see Figures 3(b) and 3(c)). However, as in the case of NaBr, no color change was observed in the aqueous dispersion of Ag nanoprisms treated with TEMEA. Ag nanoprism aqueous dispersion samples exposed to H ₂ O ₂ turned bright blue. Additionally, the extinction spectrum showed a relatively small wavelength shift (Δλ) value, but the extinction intensity was significantly reduced (see Figure 3(d)). However, this color change did not occur in Ag nanoprisms treated with TEMEA. From the above results, it was confirmed that TEMEA can dramatically improve the chemical stability of the nanoprism by effectively protecting the surface of the Ag nanoprism, thereby protecting the nanoprism from strong etchants.

4. Chemical passivation of TEMEA-treated Ag nanoprisms to iodide.

The Ag nanoprism synthesized in this example was also vulnerable to I ^- . As shown in Figure 4(a), the initially gray aqueous dispersion of Ag nanoprisms turns dark blue when exposed to NaI (final concentration of NaI ~ 0.02mM, NaI/Ag molar ratio ~ 0.05) for 60 min at room temperature. changed. The corresponding UV/Vis/NIR extinction spectra were consistent with these color changes, and the wavelength shift (Δλ) of the in-plane dipole resonance peak toward the blue direction increased with increasing reaction time up to 60 min, up to approximately 240 nm ( (see Figure 4(b)). These color changes and Δλ value measurement results suggest that the Ag nanoprisms were not significantly damaged even when exposed to 0.02 mM NaI. TEM images of Ag nanoprisms exposed to 0.02mM NaI also showed the same results (Figures 4(c) and 4(d)). In other words, the Ag nanoprism maintained its triangular shape, although its edges were slightly blunted and its size was slightly reduced.

In the present invention to improve the inherent instability of Ag nanoprisms by treating them with TEMEA, a test using I ^- as an etchant showed excellent results. The aqueous dispersion of TEMEA-treated Ag nanoprisms showed faster and more colorful changes than pure Ag nanoprisms (Figure 4) when exposed to I ^- for 1 hour (Figure 5(a)). The LSPR characteristics observed in the UV/Vis/NIR extinction spectra were consistent with these color changes. The wavelength shift (Δλ ~ 310 nm) exhibited by the TEMEA-treated Ag nanoprisms exposed to I ⁻ for 1 h was larger than that of the pure Ag nanoprisms (Δλ ~ 230) (Figure 5(b)).

As shown in Figures 5(c) to 5(f), the Ag nanoprisms treated with TEMEA were transformed into elliptical nanostructures, and the average size of these particles significantly decreased during 60 min of reaction with I ⁻ . It was confirmed that almost the same results as those obtained with NaI were obtained in experiments using KI instead of NaI at the same concentration and under the same conditions, indicating that the type of counter ion does not significantly affect the morphological development of Ag nanoprisms. These results clearly show that the surface passivation effect provided by TEMEA does not occur selectively when I ^- is used as an etchant, but rather the etching rate and degree of damage to the Ag nanoprisms are actually further increased.

5. Iodine ion (I) in water ^- ) of colorimetric sensing

The rate at which the color and spectrum change in TEMEA ^- treated Ag nanoprism colloidal dispersions exposed to I - etchant was shown to depend on the I - concentration of the aqueous dispersion, indicating that with increasing etchant concentration, Ag nanoprisms become more active. This is because it is etched quickly. As shown in Figure 5(a), the color of the Ag nanoprism colloidal dispersion changed from gray to blue in about 20 minutes in the presence of 20 μM I ^- . The rate of color change of Ag nanoprism colloidal dispersions also decreased and accelerated, respectively, when the I ^- concentration was decreased in one test and the I ^- concentration increased from this level in the other test. As a result, in Figure 6, after a fixed reaction time (here, 20 minutes), the color of the colloidal dispersion changed significantly from initial gray to cyan, blue, purple, or pink depending on the concentration of I ^- . In addition, as a result of examining the UV/Vis/NIR extinction spectrum obtained from each colloidal dispersion shown in Figure 6(b), it was found that the Ag nanoprism resonance peak gradually shifted to blue in proportion to the I ^- concentration after 20 minutes. This wavelength shift (Δλ) was plotted against I ^- concentration as shown in Figure 6(c). At this time, the standard deviation value indicated by the error bar of the curve was obtained by repeating the same experiment 5 times. In Figure 6(c), a clear correlation was observed between Δλ and I ^- concentration, and Δλ appeared to increase as the concentration of I ^- increased in the range of 0 μM to 100 μM. In summary, the TEMEA-treated Ag nanoprism colloidal dispersion exhibited distinct colors depending on I ^- concentration in the range of 0 to 100 μM, and the change in color could be visually recognized and quantified by wavelength shift (Δλ). These results clearly demonstrated that a new plasmonic sensing probe for detecting I ^- could be developed by utilizing the chemical etching of TEMEA-treated Ag nanoprisms to induce I ^- .

The high selectivity for I ^- of the sensing probe developed in this example can be confirmed by whether the Ag nanoprism colloidal dispersion maintains its original dark gray color when exposed to other ions. To test the selectivity of the detection probe developed in this example for I ^- , halide ions (F ^- , Cl ^-, and Br ^- ) and heavy metal ions (Pb ²⁺ , Mg ²⁺ , Ba ²⁺ , Zn ²⁺ , Sr ²⁺ , Cu ²⁺ , Ca ²⁺ , Al ³⁺ and Ga ³⁺ ) were injected into each Ag nanoprism colloidal suspension sample and then aged at room temperature for 1 hour. In each experiment, Ag nanoprisms were treated with 5 mM TEMEA and the final ion concentration was set at 100 μM (molar ratio of each ion to Ag ~ 0.05). After 60 minutes, all samples except the sample containing 20 μM I ⁻ maintained their initial dark gray color (see interpolation in Figure 7(b)). Referring to Figure 7(a), which shows the UV/Vis/NIR extinction spectrum of each colloidal dispersion, there was little change in the LSPR characteristics of the Ag nanoprism in all samples except the sample containing I ^- . According to Figure 7(b), which shows the wavelength shift (Δλ) value of each sample, it shows that a significant shift in the peak intensity wavelength occurred only in the presence of I ^- . At this time, the error bar in the plot represents the standard deviation value obtained by repeating the experiment three times. Furthermore, it was confirmed that the color of the colloidal dispersion of Ag nanoprisms changed in the presence of I ^- even if other halide ions existed together with I ^- . These results demonstrate the excellent selectivity of the plasmonic sensing probe for I ⁻ according to the present invention.

6. Application of detection probes to real food samples in tap water

The Ag nanoprism-based sensing probe according to the present invention was applied to detect iodide in food samples dissolved in tap water. Dried kelp was used as a food sample, and an aqueous solution containing iodide was prepared by burning the kelp and dissolving the residue in boiling tap water. According to the results of ion chromatography analysis of the tap water used, iodide above 0.1 ppm was not detected in the tap water. The iodide concentration of the final filtered aqueous solution obtained using kelp was found to be approximately 436.3 μM as a result of ion chromatography analysis. For subsequent iodide detection experiments, aqueous samples were diluted with different amounts of tap water and dispersions of TEMEA-treated Ag nanoprism dispersions were added to each diluted solution to obtain a molar ratio of iodide to Ag of 5 to 100 with a molar ratio of iodide to Ag of 0.0025 to 0.05. Final concentrations of iodide in the μM range were calculated. Then, the Ag nanoprism dispersion was aged at room temperature. After 20 minutes, the color of the colloidal dispersion changed significantly from initial gray to cyan, blue, purple, purple, or pink depending on the concentration of I ^- , as shown in Figure 8(a). The UV/Vis/NIR extinction spectrum of the colloidal dispersion is shown in Figure 8(b), showing that the resonance peak gradually shifts toward the blue direction in proportion to the I ^- concentration after 20 minutes. The wavelength shift (Δλ) was expressed against I ^- concentration as shown in Figure 8(c), where the standard deviation value indicated by the error bar of the curve was obtained by repeating the experiment three times. The value of Δλ was found to increase concomitantly with increasing I ^- concentration from 0 μM to 100 μM. These results obtained using real samples were found to be very similar to the results shown in Figure 6 obtained under laboratory conditions using deionized water and NaI. Specifically, the Δλ value of the actual sample was almost identical to the value obtained using NaI with deionized water (see Figure 9). These results show that the Ag nanoprism-based sensing probe according to the present invention is excellent in practical applications.

The present invention is not limited to the above-mentioned embodiments, but can be manufactured in various different forms, and those skilled in the art will be able to form other specific forms without changing the technical idea or essential features of the present invention. You will be able to understand that this can be implemented. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive.

Claims (7)

(a) synthesizing silver (Ag) nanoprisms; and
(b) Adding tetramethylethylenediamine (TEMEA) to the silver (Ag) nanoprism aqueous dispersion and stirring to cap the surface of the silver (Ag) nanoprism particles with tetramethylethylenediamine (TEMEA). Containing ;
Method for manufacturing silver (Ag) nanoprisms with improved chemical stability. According to paragraph 1,
In step (a),
Characterized by synthesizing silver nanoprisms by reducing the silver precursor in an aqueous mixture containing a silver precursor, polyvinylpyrrolidone (PVP), polyacrylamide (PAM), and acetonitrile. doing,
Method for manufacturing silver (Ag) nanoprisms with improved chemical stability. According to paragraph 2,
The silver precursor is silver nitrate (AgNO ₃ ),
Method for manufacturing silver (Ag) nanoprisms with improved chemical stability. Silver nanoprisms manufactured according to the manufacturing method according to any one of claims 1 to 3. A colorimetric sensor for detecting iodine ions comprising the silver nanoprism particles according to claim 4 and water. According to clause 5,
A colorimetric sensor for detecting iodine ions, wherein the silver nanoprism particles are etched into a spherical or elliptical shape by iodine ions (I ^- ). According to clause 5,
A colorimetric sensor for detecting iodine ions, characterized in that the color changes from gray to cyan, blue, purple or pink by adding iodine ions.