CN105294706A - Iron phthalocyanine nanowire with new crystal structure and preparation method of iron phthalocyanine nanowire - Google Patents

Abstract

A kind of iron phthalocyanine nanowire, the X-ray diffraction spectrum of this iron phthalocyanine nanowire (test condition: Cu _Kα1 , , 0.02°/step/2s) have characteristic peaks at the following 2θ±0.10°: 6.92°, 8.70°, 9.88°, 15.67°, 24.11°, 26.06°; and corresponding to the above 2θ, the half peak widths are 0.562 .

Description

Iron phthalocyanine nanowires with new crystal structure and preparation method thereof

technical field

The embodiment of the present invention relates to a new crystal structure iron phthalocyanine nanowire and a preparation method thereof.

Background technique

The phthalocyanine ring is a large conjugated ring with 18 π electrons, and its structure is very similar to natural porphyrin, chlorophyll and heme. The hydrogen atom in the middle of the phthalocyanine ring is replaced by a metal element to form a phthalocyanine compound; iron, as the most abundant metal element on the earth, can replace the two hydrogen atoms of the phthalocyanine ring to form iron phthalocyanine. Iron phthalocyanine is an excellent functional material. Due to its unique properties such as catalytic activity, photosensitivity, photoconductivity, photostability and nonlinearity, it has been used in the fields of catalysts, fuel cells, photoconductive materials and optical discs.

In general, different preparation conditions and methods will result in iron phthalocyanine crystals with different crystal structures and sizes, and crystals with different structures and sizes will have essential differences in properties and functions. Usually, the methods for preparing iron phthalocyanine include concentrated sulfuric acid solution recrystallization method, physical vapor deposition method, electrochemical deposition method, alumina template method, solution gradient cooling method, microwave method of iron phthalocyanine and solid state thermal cracking method in a sealed system. Wait. These preparation methods can usually obtain iron phthalocyanine crystals with crystal forms of α and β, and these crystals are mainly needle-shaped, rod-shaped, etc. in shape.

Due to the shortcomings of iron phthalocyanine crystals with these shapes, such as coarse size and low solvent solubility, and the inability to effectively control their size and structure at the nanometer level, the application of iron phthalocyanine is limited. In this way, based on the research of organic semiconductor nanomaterials by organic vapor deposition method, it can be prepared in large quantities through the regulation of temperature, flow rate of carrier gas and other conditions by organic vapor deposition method, but it is different from the existing iron phthalocyanine structure. High-purity iron phthalocyanine nanowires with nano-scale and nano-wire bundles with millimeter-scale lengths. Furthermore, the new iron phthalocyanine can be applied in different fields such as nonlinear optics, electrochemistry, photodynamic therapy, and photoconductive materials.

Contents of the invention

The embodiment of the present invention relates to a kind of iron phthalocyanine nanowire, the X-ray diffraction spectrum of described iron phthalocyanine nanowire (test condition: Cu _Kα1 , 0.02°/step/2s) has characteristic peaks at the following 2θ±0.10°: 6.92°, 8.70°, 9.88°, 15.67°, 24.11°, 26.06°; and corresponding to the above 2θ, the half-peak widths are 0.562, 0.515, 0.324, 0.502, 0.336, 0.306; corresponding to the above 2θ respectively, the relative diffraction intensities are 100%, 6.5%, 4.7%, 18.2%, 4.4%, 8.7%.

Optionally, the iron phthalocyanine nanowires have the following Fourier transform infrared spectrum (FTIR) characteristic peaks: 725cm ^-1 , 752cm ^-1 , 775cm ^-1 , 1080cm ^-1 , 1118cm ^-1 , 1165cm ^-1 , 1288cm ^-1 , 1330cm ^-1 , 1419cm ^-1 , 1493cm ^-1 , 1512cm ^-1 , 1612cm ^-1 .

Optionally, the average diameter of the iron phthalocyanine nanowires is about 70 nm.

Embodiments of the present invention also provide a method for preparing iron phthalocyanine nanowires, comprising the following steps:

a) the iron phthalocyanine raw material is placed in the heating zone in the tube furnace;

b) under a carrier gas atmosphere, heating the iron phthalocyanine raw material to a maximum of 500°C to obtain sublimated gaseous iron phthalocyanine;

c) using the carrier gas to guide the sublimed gaseous iron phthalocyanine to leave the heating area to a growth area with a lower temperature than the heating area;

d) In the growth region, iron phthalocyanine nanowires are obtained.

Optionally, in said step b), the iron phthalocyanine raw material is heated up to 490°C, preferably up to 460°C.

Optionally, the temperature of the growth region is below 150°C, preferably below 100°C, more preferably below 50°C, and most preferably at room temperature.

Optionally, in the step b), heating is carried out in a stepwise manner, preheating to 400°C first, and then stepwise raising the temperature to the highest temperature, and the stepwise heating interval is 1°C-30°C, And the heating rate is 1°C-5°C/min.

Optionally, the flow rate of the carrier gas at the inlet is 0.2L/min-0.6L/min, and the flow rate of the carrier gas when passing through the iron phthalocyanine raw material is 0.2L/min-0.6L/min.

Optionally, a gap of 60-90 mm is set between the heating area and the growth area; wherein a heat insulating material is set in the gap, and a ventilation hole is set in the heat insulating material.

Optionally, the flow rate of the carrier gas in the vent hole is 1L/min-9L/min.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the accompanying drawings of the embodiments will be briefly introduced below. Obviously, the accompanying drawings in the following description only relate to some embodiments of the present invention, rather than limiting the present invention .

Fig. 1 is the iron phthalocyanine nanowire XRD pattern that one embodiment of the present invention provides;

Figure 2 is the XRD patterns of α-iron phthalocyanine and β-iron phthalocyanine

Fig. 3 is the FTIR spectrum of iron phthalocyanine raw material and iron phthalocyanine nanowire provided by one embodiment of the present invention;

Fig. 4 is an SEM spectrum of iron phthalocyanine nanowires provided by an embodiment of the present invention.

detailed description

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention more clear, the following will clearly and completely describe the technical solutions of the embodiments of the present invention in conjunction with the drawings of the embodiments of the present invention. Apparently, the described embodiments are some, not all, embodiments of the present invention. Based on the described embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Unless otherwise defined, the technical terms or scientific terms used in the present disclosure shall have the usual meanings understood by those skilled in the art to which the present invention belongs. "First", "second" and similar words used in the patent application specification and claims of the present invention do not indicate any sequence, quantity or importance, but are only used to distinguish different components. Likewise, words like "a" or "one" do not denote a limitation in quantity, but indicate that there is at least one. Words such as "connected" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

In one embodiment of the present invention, the X-ray diffraction spectrum (test condition: Cu _Kα1 , 0.02°/step/2s) has characteristic peaks at the following 2θ±0.10°: 6.92°, 8.70°, 9.88°, 15.67°, 24.11°, 26.06; and corresponding to the above 2θ, the half-peak widths are 0.562, 0.515 .

In one embodiment of the present invention, the iron phthalocyanine nanowires have the following Fourier transform infrared spectrum (FTIR) characteristic peaks: 725cm ^-1 , 752cm ^-1 , 775cm ^-1 , 1080cm ^-1 , 1118cm ^-1 , ^1165cm -1 ¹ , 1288cm ^-1 , 1330cm ^-1 , 1419cm ^-1 , 1493cm ^-1 , 1512cm ^-1 , 1612cm ^-1 .

Figure 1 shows the X-ray diffraction spectrum of iron phthalocyanine nanowires provided by an embodiment of the present invention. The SEM of the iron phthalocyanine nanowire obtained in an embodiment of the present invention is shown in FIG. 4 .

Embodiments of the present invention also provide a vapor deposition method for preparing iron phthalocyanine nanowires, comprising the following steps:

a) the iron phthalocyanine raw material is placed in the heating zone in the tube furnace;

b) under a carrier gas atmosphere, heating the iron phthalocyanine raw material to a maximum of 500°C to obtain sublimated gaseous iron phthalocyanine;

c) using the carrier gas to guide the sublimed gaseous iron phthalocyanine to leave the heating area to a growth area with a lower temperature than the heating area;

d) In the growth region, iron phthalocyanine nanowires are obtained.

In the preparation process, in the above step a), firstly, iron phthalocyanine is introduced into the heating area in the tube furnace. Optionally, the iron phthalocyanine is placed in a sealed tube located in a tube furnace. The sealed tube can be a quartz tube, or a tube made of any other material that does not affect the crystallinity of iron phthalocyanine, including, but not limited to, tubes made of stainless steel, silicon, alumina, ceramics, glass and other materials. These materials can also be placed in sealed tubes, such as quartz tubes, in the form of substrates.

After adding iron phthalocyanine, pass the carrier gas into the heating area. The carrier gas may be, for example, nitrogen (N ₂ ), argon (Ar) or helium (He). In the presence of the carrier gas, the iron phthalocyanine is heated to a predetermined target temperature. The choice of temperature only needs to enable the raw material of iron phthalocyanine to sublimate to gas without producing other crystal forms of iron phthalocyanine. In order to effectively prevent the formation of other crystal forms of iron phthalocyanine due to excessive heating temperature, for example, in the above step b), the iron phthalocyanine raw material is heated to a maximum of 500°C, preferably a maximum of 490°C, more preferably a maximum of 470°C, and further preferably a maximum of 470°C. 460°C.

In the step b), for example, heating may be carried out in a stepwise manner. For example, preheat to 400°C first, then raise the temperature stepwise to the target temperature, and keep at this temperature for a certain period of time. The temperature increase interval of the stepwise temperature increase can be set to, for example, 1°C-30°C, preferably at a temperature increase interval of 1°C, 2°C, 5°C, 8°C, 10°C, 15°C, 20°C, 25°C or 30°C , the heating rate can be set to, for example, 1°C-5°C/min. The meaning of the temperature rise interval is, for example, if the temperature rise interval is 1° C., after raising the temperature by 1° C., the temperature is kept for a certain period of time, and then the temperature is continued to rise. The effect of adopting staged heating is that the iron phthalocyanine can be sublimated more smoothly, and a more stable iron phthalocyanine gas can be obtained, which is more conducive to the formation of iron phthalocyanine nanowires with a new crystal structure.

In the above step c), the temperature of the growth region is below 150°C, preferably below 100°C, more preferably below 50°C, and most preferably at room temperature. The temperature of the growth region is lower than that of the heating region, so that the sublimated iron phthalocyanine gas can solidify into iron phthalocyanine crystals in the growth region. The temperature in the growing area should not be too high. If it is too high, iron phthalocyanine gas will crystallize to form other crystal structures, such as β crystal form.

In step c), the iron phthalocyanine gas obtained by sublimation is quickly transported to the iron phthalocyanine nanowire growth region through the carrier gas. During the transportation process, the iron phthalocyanine sublimation gas is operated quickly to prevent the iron phthalocyanine nanowires from growing other crystal forms of iron phthalocyanine outside the growth area. Optionally, the growth zone adjoins the heating zone. Alternatively the growth area can also be remote from the heating area. Optionally, there is a certain gap between the growing area and the heating area, for example, a gap of 40-100 mm, or a gap of 50-95 mm, or a gap of 60-90 mm. Insulation material can be filled in this gap. Insulation materials include, but are not limited to, calcium silicate, aluminum silicate, Teflon, or polyurethane. Holes are provided in the heat insulating material so that the carrier gas leading the iron phthalocyanine gas can pass through. The number and diameter of the holes can be set as required. For example, the number of holes is 1-12; the diameter of the holes is 3-8mm. Through the arrangement of the holes, the flow rate (L/min) of the carrier gas when passing through the holes is greatly improved compared with the flow rate (L/min) when passing through the iron phthalocyanine raw material. Thus, the sublimation gas carrying iron phthalocyanine can quickly reach the growth region. The iron phthalocyanine crystal in the embodiment of the present invention grows, for example, in a growth region lower than 150° C., or lower than 100° C., or lower than 50° C., or grows in a room temperature region.

In the process of preparing iron phthalocyanine nanowires, it can be carried out under normal pressure. The process of preparing iron phthalocyanine nanowires can also be carried out under vacuum or pressure as required. The flow of carrier gas needs to be kept constant throughout the preparation process. The flow rate of the carrier gas at the inlet is generally 0.1L/min-1L/min, or 0.2L/min-0.5L/min. When passing through the holes in the above-mentioned heat insulating material, the flow rate (velocity) of the carrier gas can be 1L/min-20L/min, or the flow rate of the carrier gas is 1L/min-9L/min, or the flow rate of the carrier gas is 2L/min-6L/min, or the flow rate of carrier gas is 3L/min-5L/min. The carrier gas guides the iron phthalocyanine sublimation gas to pass through each temperature zone quickly, reducing the growth of crystals in areas other than the growth area.

The method of the present invention also includes the step of cleaning the quartz tube before introducing iron phthalocyanine, including, but not limited to:

(1) Use organic solvent acetone, absolute ethanol, deionized water to clean the quartz tube and the substrate to remove impurities on the quartz tube and the substrate;

(2) Use high-purity nitrogen gas to dry up residual impurities and water on the quartz tube and substrate;

(3) Vacuumize the cavity of the quartz tube by using a vacuum system before preparation to remove impurities such as air in the quartz tube.

The physical and chemical properties of the iron phthalocyanine nanowires provided in the embodiments of the present invention remain stable after long-term storage.

The implementation of the present invention will be described in detail below through examples.

Example 1:

A single temperature section open-type tube furnace with programmable temperature control. The iron phthalocyanine raw material is placed in the central position of the high temperature section of the tube furnace. The flow rate of carrier gas _N2 was set at 0.4 L/min. After passing _N2 gas for 30 minutes, heat the raw material of iron phthalocyanine. First heat to 400°C, and then raise the temperature to 420°C at a rate of 4°C/min after reaching 400°C. After reaching 420°C, keep it warm for 20 minutes, and then raise the temperature to 440°C at a rate of 4°C/min. After reaching 440°C, keep it warm for 20 minutes, and then raise the temperature to 460°C at a rate of 2°C/min. Reach 460°C and hold for 180min. The sublimated iron phthalocyanine gas is transported by the carrier gas to the growth area. After the heat preservation is completed, the heating is stopped, and N ₂ is continuously passed through for 30 minutes to obtain iron phthalocyanine nanowires.

Example 2:

On the basis of Example 1, a programmable temperature-controlled single-temperature section open-type tube furnace is used, and the flow rate at the _N2 inlet is adjusted to 0.6L/min. ℃, 500°C stepwise heating method, heating up to 500°C, holding for 300min. The growth zone is connected to the heating zone by a quartz tube with an inner diameter of 5 mm. Through small-bore tubing, the flow rate of the carrier gas was increased to 3.6 L/min. After heating, continue to ventilate for 30 minutes, then stop ventilating, and the iron phthalocyanine nanowires grow at room temperature.

Example 3:

On the basis of Example 2, a programmable temperature-controlled single-temperature section open-type tube furnace is used, and the flow rate at the _N2 inlet is adjusted to 0.6L/min. The way of heating up is to raise the temperature to 460°C and keep it warm for 300min. Obtain iron phthalocyanine nanowires.

Example 4:

The experimental conditions were changed: the substrate material was ordinary glass, the temperature and heating method were repeated in Example 1, the temperature reached 460° C. and kept for 180 minutes, then the heating was stopped, and the preparation of the iron phthalocyanine nanowires was completed, and the iron phthalocyanine nanowires were collected.

The above descriptions are only exemplary implementations of the present invention, and are not intended to limit the protection scope of the present invention, which is determined by the appended claims.

Claims (10)

1. a kind of iron phthalocyanine nanowire, it is characterized in that the X-ray diffraction spectrum (test condition: Cu _{K α} 1 of described iron phthalocyanine nanowire, 0.02°/step/2s) has characteristic peaks at the following 2θ±0.10°: 6.92°, 8.70°, 9.88°, 15.67°, 24.11°, 26.06°; and corresponding to the above 2θ, the half-peak widths are 0.562, 0.515, 0.324, 0.502, 0.336, 0.306; corresponding to the above 2θ respectively, the relative diffraction intensities are 100%, 6.5%, 4.7%, 18.2%, 4.4%, 8.7%. 2. The iron phthalocyanine nanowire according to claim 1, characterized in that the iron phthalocyanine nanowire has the following Fourier transform infrared spectrum (FTIR) characteristic peaks: 725cm ^-1 , 752cm ^-1 , 775cm ^-1 , 1080cm ^-1 , 1118cm ^-1 , 1165cm ^-1 , 1288cm ^-1 , 1330cm ^-1 , 1419cm ^-1 , 1493cm ^-1 , 1512cm ^-1 , 1612cm ^-1 . 3. The iron phthalocyanine nanowire according to claim 1 or 2, characterized in that the average diameter of the iron phthalocyanine nanowire is about 70 nm. 4. A method for preparing iron phthalocyanine nanowires, comprising the following steps: a) the iron phthalocyanine raw material is placed in the heating zone in the tube furnace; b) under a carrier gas atmosphere, heating the iron phthalocyanine raw material to a maximum of 500°C to obtain sublimated gaseous iron phthalocyanine; c) using the carrier gas to guide the sublimed gaseous iron phthalocyanine to leave the heating area to a growth area with a lower temperature than the heating area; d) In the growth region, iron phthalocyanine nanowires are obtained. 5. The method according to claim 4, characterized in that in said step b), the iron phthalocyanine raw material is heated to a maximum of 490°C, preferably a maximum of 460°C. 6. The method according to claim 4, characterized in that the temperature of the growth region is below 150°C, preferably below 100°C, more preferably below 50°C, most preferably at room temperature. 7. The method according to any one of claims 4-6, characterized in that in the step b), heating is carried out in a stepwise manner, preheated to 400°C first, and then stepped up to the highest temperature , the heating interval of the stepwise heating is 1°C-30°C, and the heating rate is 1°C-5°C/min. 8. The method according to any one of claims 4-6, characterized in that, the flow rate of the carrier gas at the inlet is 0.2L/min-0.6L/min, and the carrier gas passes through the phthalein The flow rate of ferrocyanine raw material is 0.2L/min-0.6L/min. 9. The method according to claim 8, characterized in that, a gap of 60-90 mm is set between the heating zone and the growth zone; wherein a heat insulating material is set in the gap, and a through-hole is set in the heat insulating material. stomata. 10. The method according to claim 9, characterized in that, the flow rate of the carrier gas in the vent hole is 1 L/min-9 L/min.