KR100891489B1 - Nanoporous silca-polyaniline hybrid material - Google Patents

Abstract

A nanoporous silica-polyaniline hybrid material is provided to show high periodicity, electroactivity, electrochromism, and pH responsivity of polyaniline chains in a silica nanochannel. A nanoporous silica-polyaniline hybrid material comprises: a silica backbone which has a nano channel shape by a silicate network; polyaniline chains containing nitrogen bonded with a C1-C5 straight hydrocarbon and Si of the silica backbone; and a micelle which is formed by naphthalene sulfonic acid electrostatically bonded with the polyaniline chains. The polyaniline chains form a uniform membrane inside the silica nanochannel. The nanoporous silica-polyaniline hybrid material has arranged hexagonal array.

Description

Nanoporous Silca-Polyaniline Hybrid Material

The present invention relates to novel nanoporous silica-polyaniline hybrid materials and methods for their preparation.

Hybrid materials of organic-inorganic compounds incorporate chemical functionalities, various soft (organic compound) materials, and mechanically strong (inorganic compound) backbones to synergize organic (inflexible, processable) and inorganic (hard, thermally stable) components. Characterization and leads to interesting research in basic and applied fields.

Aligned mesoporous silica, such as MCM, is one of the host materials capable of forming hybrid materials with organic molecules / polymers. Silica-conductive polymer hybrids are prepared by encapsulating a conductive polymer in mesoporous silica channels with potential for future applications such as energy / electron transfer nanodevices, chemical sensors.

Since Kresge and co-workers have reported the synthesis of the M41S family of silicates through the surfactant template sol-gel process, the variety of mesoporous silicas sorted on the basis of various materials has varied in size (smaller organic compounds than polymers), shape And host molecules of functionality. Some studies have since been made on the encapsulation of organic polymers in channels of mesoporous silica.

To date, mesoporous silica-organic compound hybrids have usually been prepared by co-condensation reactions of organic silanes or by post-synthetic grafting or covalent versus non-covalent bonds. The cocondensation method is preferred for the postsynthesis route because it minimizes processing steps and results in more uniform dispersion of guest materials. One pot cocondensation synthesis provides higher loading of organic compound functionalities.

Conjugate polymers are important because they possess the mechanical properties of polymers with processability and controllable optoelectronic properties, and have the use of light emitting diodes, field effect transistors, solar cells, memory devices, and other devices. Among the conductive polymers, polyaniline (PANI) is of greater interest due to the simplicity of synthesis, the nature of the redox reaction and the environmental stability. Further, the interesting properties of the PANI have found applications such as electrochromic devices, electrophoresis, catalysts, and electronic devices.

A study of the formation of PANI or its derivatives within the pores of MCM-41 has been reported. Aniline was absorbed inside the pore wall of silica and subsequently polymerized with PANI (a low degree of PANI loading and doping range of the PANI chain was observed without control over the periodicity of the PANI chain in the silica channel).

However, there are still many challenges and barriers in terms of the degree of encapsulation of the polymer in the pores and the periodicity of the structural alignment and functions of the polymer in the channels.

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It is an object of the present invention to provide a novel nanoporous silica-polyaniline hybrid material having high periodicity, electroactivity, electrochromicity, and pH sensitivity of polyaniline (PANI) chain in silica nanochannels and a method for preparing the same. It is also an object of the present invention to provide a membrane formed of the nanoporous silica-polyaniline hybrid material and a method for producing the same.

The present invention provides a polyaniline (PANI) chain comprising a nano-channel silica skeleton by a silicate network, a nitrogen atom (N) connected by Si inside the silica skeleton by a linear hydrocarbon having 1 to 5 carbon atoms, and the polyaniline A micelle formed by β-naphthalene sulfonic acid (NSA) bonded in an electrostatic interaction with the chain,

The polyaniline chain provides a nanoporous silica-polyaniline hybrid material, which forms a uniform film inside the nanochannel wall.

In addition, the present invention,

Dissolving trimethoxysilylpropylaniline (TMSPA) in β-naphthalene sulfonic acid (NSA) and stirring;

Adding ammonium persulfate (APS) to the solution prepared above; And

It provides a method for producing a nanoporous silica-polyaniline hybrid material comprising the step of recovering the precipitate formed in the step, washing and drying.

The present invention also provides a nanoporous silica-polyaniline hybrid material film formed of the nanoporous silica-polyaniline hybrid material.

In addition, the present invention,

Dissolving trimethoxysilylpropylaniline (TMSPA) in β-naphthalene sulfonic acid (NSA);

Electrolyzing the solution prepared above in a three electrode cell assembly consisting of an ITO working electrode, an Ag / AgCl reference electrode, and a platinum wire auxiliary electrode; And

It provides a method for producing a nanoporous silica-polyaniline hybrid material film comprising recovering the film formed on the surface of the ITO working electrode.

The nanoporous silica-polyaniline hybrid material of the present invention has high periodicity, electroactivity, electrochromicity, and pH sensitivity of polyaniline (PANI) chains in silica nanochannels, and higher loading of polyaniline (PANI) in silica nanochannels ( It can be used in various applications such as light emitting diodes, field effect transistors, solar cells, memory devices, secondary batteries, energy / electron transfer nano devices, chemical sensors, etc. In addition, the nanoporous silica-polyaniline hybrid material of the present invention can be effectively used for drug delivery means and energy devices.

In addition, the nanoporous silica-polyaniline hybrid material film of the present invention formed of the nanoporous silica-polyaniline hybrid material may also be utilized for such applications.

The present invention provides a polyaniline (PANI) chain comprising a nano-channel silica skeleton by a silicate network, a nitrogen atom (N) connected by Si inside the silica skeleton by a linear hydrocarbon having 1 to 5 carbon atoms, and the polyaniline A micelle formed by β-naphthalene sulfonic acid (NSA) bonded in an electrostatic interaction with the chain,

And wherein said polyaniline chain forms a uniform film inside said nanochannel wall.

The nanoporous silica-polyaniline hybrid material is characterized by having an aligned hexagonal arrangement.

In the above, the C 1-5 straight chain hydrocarbon is preferably propylene.

The homogeneous film inside the aforementioned nanochannel walls does not completely block the nanochannel pores.

The nanoporous silica-polyaniline hybrid material is characterized by having a high periodicity, electroactivity, electrochromicity, pH sensitivity of the PANI chain in the silica nanochannels.

In addition, the present invention

Dissolving trimethoxysilylpropylaniline (TMSPA) in β-naphthalene sulfonic acid (NSA) and stirring;

Adding ammonium persulfate (APS) to the solution prepared above; And

It relates to a method for producing a nanoporous silica-polyaniline hybrid material comprising the step of recovering, washing and drying the precipitate formed in the step.

The ammonium persulfate (APS) is preferably added in a dropwise while stirring at a constant rate, and the dropwise is preferable in view of efficiently polymerizing at 2 to 8 ° C.

In the above method, the trimethoxysilylpropylaniline (TMSPA) molecules are formed in spherical micelles by an electrostatic interaction between -NH ₂ group in TMSPA and SO ^{3 -} group in β-naphthalene sulfonic acid (NSA). Perform the self assembly process.

The present invention also provides

A nanoporous silica-polyaniline hybrid material film formed of the nanoporous silica-polyaniline hybrid material.

The nanoporous silica-polyaniline hybrid membrane has electroactivity, is electrochemically stable, and has electrochromic properties.

The present invention also provides

Dissolving trimethoxysilylpropylaniline (TMSPA) in β-naphthalene sulfonic acid (NSA);

Electrolyzing the solution prepared above in a three electrode cell assembly consisting of an indium tin oxide (ITO) working electrode, an Ag / AgCl reference electrode, and a platinum wire auxiliary electrode; And

A method for producing a nanoporous silica-polyaniline hybrid material membrane comprising recovering a film formed on the surface of the ITO working electrode.

In the above production method, electrolysis is preferably performed by reversibly circulating the electric potential in the range of 0.0 V to +1.0 V to form a nanolayer.

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

In order to indicate the novel properties of the nanoporous silica-polyaniline hybrid material of the present invention, the material is simply named KGM-1 (Kyungbuk National University Material 1).

KGM Manufacture of -1

KGM-1 is synthesized as a green color powder by one pot and simple chemical methods. In a typical synthesis, a solution of trimethoxysilylpropylaniline (TMSPA) in β-naphthalene sulfonic acid (NSA) undergoes simultaneous oxidation of the aniline units resulting in polymerization and hydrolysis of silica units (FIG. 1). At this time, the simultaneous formation of polyaniline (PANI) chains is observed as depicted in the silicate network (as similar to the formation of porous silica such as MCM-41) and in FIG. 1. In general, silica-polymer hybridization involves organic alteration of the initial silica walls resulting in functionalized silica as precursor. Furthermore, post-synthesis reactions involving the groups in the functionalized silica form polymer units in the channels (pores) of the mesoporous silica. The one-pot method used for the preparation of KGM-1 avoids the hassle of the multi-step processes generally reported for the production of silica polymer hybrids.

KGM -1 x- Lay diffraction ( XRD ) pattern

The X-ray diffraction (XRD) pattern of KGM-1 clearly explains the combined presence of the aligned silicate network and the PANI chain. The small angle XRD pattern of the synthesized KGM-1 (FIG. 2) shows a strong diffraction peak at 1.2 ° (d = 74 Hz) and two well resolved weak diffraction peaks at 4.23 ° and 4.72 °, respectively, labeled on the silica side. The XRD pattern of the KGM-1 is similar to the porous MCM-41 with a well-aligned hexagonal array of one-dimensional channel structures formed through the aid of surfactants. The inter-planar spacing d ₁₀₀ is relatively higher than MCM-41 made with surfactant, having an aliphatic chain length greater than 22. The wide angle XRD pattern of KGM-1 (Fig. 2). Inset) shows reflection at 20.2 ° (d = 11.47 mmW) with shoulder around 30.3 °, which characterizes amorphous polyaniline (PANI). 20.2 ° (d = 11.47 mmW) The crystal region size is much smaller than the conventional PANI (30-70 kHz).

KGM -1 is N ₂  Adsorption-Desorption Measurement

KGM-1 is nanoporous as evidenced from the N ₂ adsorption-desorption measurement. The KGM-1 N ₂ adsorption-desorption isotherm is a typical reversible type IV adsorption as defined by IUPAC. KGM-1 exhibits a narrow magnetic hysteresis curve of type H1 with a change in adsorption of about P / P ₀ = 0.20, which is characteristic of materials with uniform holes with an open cylindrical structure. These N ₂ adsorption features indicate that PANI can be formed as a uniform film inside the pore wall of silica without completely blocking the pores. If the film of PANI is thickly heterogeneously formed in the cylindrical pores of the silica, the channels in the silica will block and a wide magnetic hysteresis curve will appear in the N ₂ adsorption isotherm. KGM-1 has a pore diameter of 2.4 nm, an area of 16 × 10 ⁻³ cm ³ / g and 40 m ² / g, as determined from the BET isotherm and BHJ method, respectively. The holes in the KGM-1 are narrow, indicating that PANI is formed in the silica holes. KGM-1 has a large wall thickness (6.11 nm) because hydrolysis of silicates occurs through a three-dimensional crosslinking process, while at the same time PANI is formed in the pores of silica.

The results of the XRD analysis and the N ₂ adsorption-desorption measurement indicate that KGM-1 consists of PANI units in the nanochannel of the silicate network and silica backbone.

KGM Formation mechanism of -1

In general, MCM type honeycomb structures are formed by sol-gel pathways involving organic silicate precursors templated by self-assembled amphiphilic surfactants. However, the preparation of KGM-1 is not related to surfactants with long hydrophobic chains. NSAs with hydrophobic naphthalene units and sulfonate head groups are used for the preparation of KGM-1. NSA acts not only as a dopant for PANI units in KGM-1, but also as a micelle inducer during the formation of KGM-1. The formation of KGM-1 is thought to have the following stages (FIG. 1). Initially, NSA molecules exist as spherical micelles in aqueous medium. TMSPA molecules self-assemble in the spherical micelles through electrostatic interactions between —NH ₂ groups in TMSPA and SO ^{3 −} groups in NSA (FIG. 1A). This self-assembled structure is oxidized by the addition of ammonium persulfate (APS). Green colored precipitate (KGM-1) is obtained by the addition of APS solution (FIG. 1B). APS oxidizes the -NH ₂ group in the TMSPA and initiates polymerization of aniline. At the same time, continuous processes such as hydrolysis of -OMe and condensation of -OH groups in TMSPA form a silicate network (FIG. 1B). Aromatic amine groups in the TMSPA are expected to catalyze the hydrolysis. The efficiency of this amine as a catalyst for the hydrolysis of orthosilictes has been described previously. TMSPA molecules may exist outside the micelle as well as within the spherical micelles. The amine groups of the TMSPA molecules present outside of the micelles catalyze the hydrolysis of the silicates to form a silicate network. The formation mechanism of KGM-1 is likely to be analogous to the biological production of silica from nucleophilic amines that act as catalysts for silica and silica production to precipitate proteins at pH and room temperature in the shell. Therefore, KGM-1 has a silicate network as well as a PANI chain covalently linked in the silica backbone. The presence of binding of silicate networks and PANI units in KGM-1 is confirmed from results from high resolution transmission electron microscopy (HRTEM), elemental analysis, ultraviolet-visible spectroscopy, and cyclic voltmmetry.

KGM -1 and Fired KGM -1 High Resolution Transmission Electron Microscopy ( HRTEM ) image

3 shows a high resolution transmission electron microscope (HRTEM) image of the KGM-1 and calcined KGM-1. The particles of KGM-1 are spherical in shape with a diameter in the range of 0.5-1.5 μm (FIG. 3A). Due to the presence of amorphous PANI in the pores of silica, an amorphous phase-like structure is seen in the particles of KGM-1 (FIG. 3C). HRTEM images of calcined KGM-1 (FIGS. 3B, 3D, 3E) show the presence of well bounded, uniform, aligned nanosized pores similar to the MCM-41 type porous channel structure of nanospheres. The firing of KGM-1 breaks the PANI chains and improves the contrast and stability of the sample to the electron beam. As a result, nanoscale structures can be seen in the holes. In the fired KGM-1, the structure of the holes is hexagonal and it is clear that they are aligned (Fig. 3E).

KGM -1's Si Ratio of: N

KGM-1 has a Si: N ratio 10 that is much greater than the ratio of Si: N (˜2.0) of trimethoxysilylpropylaniline (TMSPA). This clearly demonstrates the formation of a three-dimensional silicate network as depicted in FIG. 1. The wall thickness (74 ms) for KGM-1, which is very large compared to MCM-41, ensures the larger Si: N ratio (10). KGM-1 has a clear ratio of S and a ratio of Si: N of 0.4. Element K in KGM-1 is derived from sulfonate ions present as dopant ions for the protonated amine / imine units of PANI. This indicates that PANI chains are doped in KGM-1. Many factors affecting the electrical properties of PANI, such as crystal structure, Polaron mobility, concentration of grain boundaries, the presence of ionic species, and doping levels, are considered as dominant regulators of electrical conductivity. Can be. It is interesting that KGM-1 is an electrical conductor with an electrical conductivity of 8 X 10 ⁴ S / cm. The electrical conductivity of KGM-1 is much higher than pure silica and relatively lower than conventional PANI with similar range of doping. This may be due to the presence of an insulated silicate network in KGM-1.

KGM - 1 of  pellicle

An interesting feature for KGM-1 is that it can be obtained with thin films of the desired thickness. KGM-1 is deposited into a thin film by an electrochemical (cyclic voltammetry) method. 4 shows a cyclic voltage-current diagram (CV) showing a film by film growth of KGM-1 on the surface of an indium tin oxide (ITO) working electrode. In the anodic scan of the first potential, a peak corresponding to the oxidation of the -NH ₂ group in TMSPA was observed at 0.80 V. In the reverse scan, two peaks corresponding to the reduction of the oligomer or polymer chains of the aniline units appeared at 0.32 V and 0.50 V. For the second and successive potential cycles, positive peaks at ˜0.52 V and ˜0.66 V were observed with complementary reducing waves at ˜0.43 V and ˜0.58 V, respectively. The gradual increase in the peak current values for these redox processes suggests a continuous production of electrically active KGM-1 at the surface of the working electrode. The KGM-1's cyclic voltammetry has several interesting features. First, the redox peaks are from the PANI units present in KGM-1 to the intermediate reduction (E) structure of the leuco emeraldine (LE) structure and of the intermediate reduction (E) structure. Can be assigned to a reversible conversion to a pernigraniline (P) type structure. The positions of these redox interconversion peaks of PANI units in KGM-1 differ markedly from those known for conventional PANI. For conventional PANI, the transition from LE to E occurs at ˜0.1 to 0.3 V. However, for KGM-1, the interconversion from LE to E occurs at much higher positive potential (0.52 V). Secondly, the film of KGM-1 is formed by the film by film deposition. Second, at the end of the potential cycle, the film thickness of KGM-1 was estimated to be ˜15 nm. For successive cycles, the film thickness continued to increase by 80-100 nm for one cycle. These observations indicate the formation of a film of nanolayers of KGM-1 on the surface of the working electrode.

KGM -1 membrane properties

Membrane of KGM-1 has electric activity as confirmed by cyclic voltammetry. CV of the membrane of KGM-1 on the surface of the ITO electrode shows reversible electrochemical properties in the potential range of 0.0-1.0 V (FIG. 4). CV of the membrane of KGM-1 shows two redox waves at 0.40 to 0.50 V and 0.58 to 0.62 V, respectively (FIG. 4, inset). The redox properties of KGM-1 originate from the PANI units therein. However, the redox process for membranes of KGM-1 occurs in different potential regions compared to conventional PANI with linear chains of aniline units. For conventional PANI, peaks are observed in the potential range of 0.18-0.25 V and 0.60-0.80 V, respectively, corresponding to polaronic emaraldine formation and dipolaronic pernigraniline formation.

However, the conversion of the PANI units in KGM-1 to the polar form occurs at much higher oxidation potentials (0.50 V) compared to linear PANI chains. Some reasons for this phenomenon are considered as follows. The electron band confinement effect of the PANI unit due to the insulating silica backbone, the presence of PANI units in other structural arrangements, and the presence of PANI units in silica nanochannels is considered for that reason. Importantly, the redox process in KGM-1 is electrochemically reversible (FIG. 4, inset), which implies the suitability of KGM-1 for application in secondary cells and the like. For various scan rates, the membrane CV _S of KGM-1 recorded in TMSPA free from backgrounded electrolyte indicates the electrochemical stability of the membrane. The redox peak positions do not shift with changes in scan speed. The peak current versus scan rate configuration at the redox peaks is linear indicating that the membrane of KGM-1 is confined, electrochemically stable and electroactive.

KGM -1 ultraviolet light Line of sight  spectrum

The ultraviolet-visible spectrum of KGM-1 indicates that the PANI unit in KGM-1 has an electron band different from that of the PANI chain in conventional PANI. The spectrum of KGM-1 in DMF shows three peaks with a center of approximately 350 nm, 420 nm and 590 nm (FIG. 5). In addition, long absorption tails are observed that extend beyond 700 nm. The approximate electron bands of 420 nm and 590 nm are ΠΠ * polarons, respectively. It corresponds to a polaron excitation transition and the excitation transition of quinoid rings of the PANI chain. There are two prominent electronic features for KGM-1 that suggest that PANI in KGM-1 has a different chain arrangement than conventional PANI. First, the [pi] * transition band appears at 350 nm for KGM-1 as opposed to the band at 320 nm for conventional PANI. The red shift in the ΠΠ * transition to KGM-1 suggests a long chain length of aniline units in PANI. Perhaps the aniline units in KGM-1 are linked in a ring / cycle form in a spherical silicate network (FIG. 1C). This interesting feature of the PANI chain in KGM-1 causes the ΠΠ * transition of KGM-1 to shift at longer wavelengths compared to the linear PANI chain for the initial PANI. Second, there is a continuous free carrier tail in the ultraviolet-visible spectrum of KGM-1. This free carrier tail is believed to result from the confinement effect of other types of PANI chains in KGM-1 and / or PANI chains in the silica nanochannels.

KGM Electrochromic behavior of -1 membrane

The KGM-1 membrane changes color from yellow at −0.10 V to cyan at +0.5 V and dark green at +0.70 V and exhibits reversible electrochromic behavior. Ultraviolet-visible spectroscopic electrochemical data was collected by recording the ultraviolet-visible spectrum in real time for KGM-1 while maintaining the potential at different values (FIG. 5, inset). The electrochromic change in the PANI unit of KGM-1 differs significantly from the conventional linear PANI. KGM-1 is yellow corresponding to PANI in LE form at -0.10 V, and green corresponding to E form of PANI whose potential exceeds 0.6V. The discoloration change of LE and E forms of PANI is consistent with the redox transition known for KGM-1 by cyclic voltammetry (CV) (FIG. 4). The electrochromic change from LE (yellow) form to E (green) form for KGM-1 occurs above 0.50 V, whereas the electrochromic change from LE form to E form for conventional PANI has a very low potential. Occurs at (~ + 0.2 V).

KGM -1 spectroscopic electrochemical properties

The KGM-1 spectroscopic electrochemical properties are described in detail. The yellow film of KGM-1 (LE form) (+0.1) has an absorption band around 410 nm, around 530 nm and greater than 800 nm. The blue-green film of KGM-1 (form E) has electron bands around 440 nm, 590 nm, and 790 nm. And the dark green film of KGM-1 (P form) shows bands at 370 nm and 780 nm. However, linear PANI (conventional) shows a peak at 320 nm for the LE form, a broad band above 700 nm, a peak at 320 nm, 420 nm for the E form, and a wide band above 700 nm. Peaks at 310 nm and 600 nm for the P form. In addition, the significant difference between the electrochemical behavior of PANI units and linear PANI (conventional) in the KGM-1 supports other types of arrangement (ring / cycle) of aniline units in KGM-1. In addition, the restraining effect that may affect the electron band in the PANI unit in KGM-1 cannot be excluded. As far as the inventors are aware, this is the first report on the electrochemical behavior of silica-polyaniline hybrid nanostructure materials. The KGM-1 membrane also exhibits a reversible color change from yellow to green for pH changes from 10 to 2 and vice versa due to the quantization-dequantization process.

KGM Conclusion for -1

Therefore, KGM-1 is similar to MCM-41 type silica material and exhibits the electroactivity, electrochromic, and pH sensitivity of conductive polymers in silica-conductive polymers, and is a novel material with an ordered hexagonal arrangement of nanoporous. It is clear that KGM-1 type materials can be prepared by tunable textural parameters applied in biomolecule detection and optoelectronics. KGM-1 also represents a reversible redox transition that can be effectively used for drug delivery means and energy devices.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the following examples are provided to illustrate the present invention, and the present invention is not limited to the following examples and may be variously modified and changed.

Example  One: KGM -1 Preparation of Powder (Chemical Method)

In the present invention, trimethoxysilylpropylaniline (TMSPA), ammonium persulfate (APS) and β-naphthalene sulfonic acid (NSA) were purchased from Aldrich.

50 mM TMSPA was dissolved in 50 mM NSA and the solution was stirred for 2 hours. 10 mL of 0.5 M APS solution was added dropwise for 2 hours with stirring at 5 ° C. at constant rate. A dark green precipitate, KGM-1, was obtained. The precipitate was washed with distilled water and dried in a vacuum oven at 60 ℃.

Example  2: KGM Preparation of --1 Membrane (electrochemical method)

Cyclic voltammetry was performed using an EG & G PAR 283 constant voltage / constant current device (Potentiostat / Galvanostat). TMSPA solution (50 mM) in NSA (1M) was in the range of 0.0 V to +1.0 V in three electrode cell assemblies consisting of an ITO working electrode, Ag / AgCl reference electrode, and a platinum wire auxiliary electrode, respectively. It was delivered by reversibly circulating the potential. A green colored film (KGM-1) was formed on the surface of the ITO electrode. The thickness of the KGM-1 membrane was measured by schematic integration of that region under the CV. The electroactivity and stability of the coated KGM-1 membrane was studied by recording the cyclic voltammetry curve of the KGM-1 membrane in 1 M NSA at different potential scan rates.

Test Example  One: KGM The organization of -1 (powder) morphology And structure observation

The grain structure of KGM-1 powder was investigated by a high resolution transmission electron microscope (HRTEM) (JEOL, JEM-ARM1300S) with a field emission electron gun operated at 1250 kV. X-rey diffraction patterns of the samples were collected using a D8-Advanced Bruker AXS diffractometer using Cu Kα radiation. N ₂ adsorption-desorption isotherms (Brunauer-Emmett-Teller) measurements were performed using Quantachrome Autosorb-1 with nitrogen as adsorbent at 77 K. The samples were degassed for 2 hours at 200 ° C. under vacuum prior to measurement. Ultraviolet-vis spectroscopy was recorded using a Shimadzu UV-2101 spectrophotometer at room temperature in the range of 300-800 nm.

Test Example  2: KGM -1 electrochromic of membrane

A KGM-1 film having a thickness of about 15 to 100 nm was coated on the surface of ITO by cyclic voltammetry. Spectroelectrochemical experiments were performed in a quartz cuvette 1 cm path length by assembling a cell with ITO as working electrode, Ag / AgCl as reference electrode and platinum wire as auxiliary electrode. Ultraviolet-vis spectroscopy was recorded simultaneously, maintaining the potential in the range of -0.1 V to 0.7 V.

The nanoporous silica-polyaniline hybrid material of the present invention has high periodicity, electroactivity, electrochromicity, and pH sensitivity of polyaniline (PANI) chains in silica nanochannels, and higher loading of polyaniline (PANI) in silica nanochannels As it is possible to load, it can be used for various applications such as light emitting diodes, field effect transistors, solar cells, memory devices, secondary batteries, energy / electron transfer nano devices, chemical sensors, and the like. In addition, the nanoporous silica-polyaniline hybrid material of the present invention can be effectively used for drug delivery means and energy devices.

1 illustrates the formation mechanism of the nanoporous silica-polyaniline hybrid material of the present invention.

(a) Spherical micelles (partial) of NSA-TMSPA self-assembly

(b) simultaneous polymerisation and condensation

(c) polyaniline in nanochannels of silica

Figure 2 graphically depicts the small angle XRD pattern and the wide angle XRD pattern (inset) of the nanoporous silica-polyaniline hybrid material of the present invention.

FIG. 3 shows high resolution transmission electron microscopy (HRTEM) images of nanoporous silica-polyaniline hybrids and calcined nanoporous silica-polyaniline hybrids [a, c: Images for nanoporous silica-polyaniline hybrids ( c different magnification picture); b, d, e: Images of calcined nanoporous silica-polyaniline hybrids (d is another magnification of b, e is an enlarged image of the box area of d).

FIG. 4 shows a cyclic voltammogram (CV) showing a film by film growth of nanoporous silica-polyaniline hybrid material on the surface of an indium tin oxide (ITO) working electrode. Recorded during formation of the silica-polyaniline hybrid (TMSPA = 50 mM, NSA = 1 M, scan rate; 100 mV / sec), insertability: cyclic voltage-current diagram (NSA = 1 M, scan rate) of the membrane of KGM-1 ; 100 mV / sec).

FIG. 5 shows the ultraviolet-visible spectrum of a nanoporous silica-polyaniline hybrid material, and the inserted graph is a real-time spectroscopic electrochemical analysis graph of the nanoporous silica-polyaniline hybrid material (ultraviolet-visible spectra are respectively a:- Collected at an application potential of 0.1 V, b: 0.1 V, c; 0.3 V, d: 0.5 V, e: 0.7 V).

Claims (11)

Nano-channel silica skeleton, by silicate network A polyaniline (PANI) chain comprising a nitrogen atom (N) connected by Si in the silica skeleton and a straight chain hydrocarbon having 1 to 5 carbon atoms, and A micelle formed by β-naphthalene sulfonic acid (NSA) bonded in an electrostatic interaction with the polyaniline chain, And wherein said polyaniline chain forms a uniform film inside said nanochannel wall. The nanoporous silica-polyaniline hybrid material of claim 1, wherein the nanoporous silica-polyaniline hybrid material has an aligned hexagonal arrangement. The nanoporous silica-polyaniline hybrid material according to claim 1, wherein the C1-5 straight chain hydrocarbon is propylene. The nanoporous silica-polyaniline hybrid material of claim 1, wherein a uniform film inside the nanochannel wall does not completely block the nanochannel holes. Dissolving trimethoxysilylpropylaniline (TMSPA) in β-naphthalene sulfonic acid (NSA) and stirring; Adding ammonium persulfate (APS) to the solution prepared above; And A method for producing a nanoporous silica-polyaniline hybrid material comprising recovering, washing and drying the precipitate formed in the step. 6. The method of claim 5, wherein ammonium persulfate (APS) is added dropwise with stirring at a constant rate. 7. A process according to claim 6, wherein the addition of ammonium persulfate (APS) is carried out at 2-8 < 0 > C. 7. The trimethoxysilylpropylaniline (TMSPA) molecules of claim 6, wherein the trimethoxysilylpropylaniline (TMSPA) molecules are spherical by an electrostatic interaction between the —NH ₂ group in TMSPA and the SO ^{3 −} group in the β-naphthalene sulfonic acid (NSA). A method for producing a nanoporous silica-polyaniline hybrid material, characterized in that the self-assembly is performed in a micelle. A nanoporous silica-polyaniline hybrid material membrane formed from the nanoporous silica-polyaniline hybrid material of any one of claims 1 to 4. Dissolving trimethoxysilylpropylaniline (TMSPA) in β-naphthalene sulfonic acid (NSA); Electrolyzing the solution prepared in three electrode cell assemblies consisting of an indium tin oxide (ITO) working electrode, an Ag / AgCl reference electrode, and a platinum wire auxiliary electrode; And Recovering the film formed on the surface of the ITO working electrode. The method of claim 10, wherein the electrolysis is performed by reversibly circulating a potential in the range of 0.0 V to +1.0 V. 12.

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