CN102817081B - Preparation method of flaky iron sulfide single crystal nano-material - Google Patents

Abstract

The present invention relates to a preparation method of flake iron ferric tetrasulfide nanometer single crystal. The method comprises the following steps: (1) mixing iron source with trioctyl phosphorus oxide, dissolving them in oleylamine, stirring and passing nitrogen or argon After the oxygen is removed by gas, the iron source precursor is obtained; (2) the iron source precursor is heated and stirred in an oil bath to obtain the iron source solution; (3) the sulfur source is dissolved in oleylamine, and the oxygen is removed by stirring and argon or nitrogen , to obtain the sulfur source solution; (4) extract the sulfur source solution with a needle after being heated, and quickly inject it into the iron source solution, and then heat up the oil bath for heating the iron source to react to obtain the colloid of sheet-shaped iron tetrasulfide nano single crystal; (5) When the colloid of flake-shaped iron tetrasulfide nano single crystal is cooled to room temperature, add chloroform-ethanol mixed solution to wash and centrifuge for several times until the upper layer of centrifugation liquid is colorless, and then obtain flake single-phase iron tetrasulfide nano single crystal. The product obtained by the invention has uniform particle size and shape, good process repeatability and stable quality.

Description

A kind of preparation method of flaky iron tetrasulfide nanometer single crystal

technical field

The invention relates to a preparation method of ferric tetrasulfide, in particular to a preparation method of sheet-shaped ferric ferric sulfide nano single crystal.

Background technique

As a magnetic material, iron tetrasulfide is a ferromagnetic material. Ferromagnetic materials are widely used in the industrial field, and can be used as microwave absorbing materials, magnetic recording materials, magnetic liquids, and also have a wide range of applications in the field of biomedicine. Iron tetrasulfide can be used in cancer hyperthermia therapy, and its magnetic properties make this material promising as a medium for targeted drug delivery, which can be used in the medical field in the near future (M. Posfai, P. R. Buseck, D. A. Bazylinski and R. B. Frankel, Iron sulfides from magnetotactic bacteria; structure, composition, and phase transitions [J]. Journal of the Mineralogical Society of America. 1998, 83 (11-12), 1469-1481; . S. Chang, S. Savitha, S. Sadhasivam, C. K. Hsu and F. H. Lin, Fabrication, characterization, and application of greigite nanoparticles for cancer hyperthermia [J]. Journal of Colloid and Interface Science. 2011, 363, 314-319.).

Thermal injection method is an effective method for easily synthesizing monodisperse and highly fluorescent semiconductor nanocrystalline materials (Z. T. Zhang, B. Zhao and L. M. Hu, PVP Protective Mechanism of Ultrafine Silver Powder Synthesized by Chemical Reduction Processes [J ]. Journal of solid state chemistry. 1996, 121, 105-110.). Researchers have successfully synthesized CdTe, CdSe, CdS, ZnS monodisperse nanocrystals by hot injection method (C. de. M. Doneg, P. Liljeroth and D. Vanmaekelbergh; Physicochemical Evaluation of the Hot-Injection Method, a Synthesis Route for Monodisperse Nanocrystal [J]. Small. 2005, 1(12), 1152-1162.; C. B. Murray, D. J. Norris and M. G. Bawendi, Synthesis and characterization of nearly monodisperse CdE ( E= sulfur, selenium, tellurium) semiconductor nanocrystallites [J]. J. Am. Chem. Soc. 1993, 115, 8706-8715.; J. V. Williams, N. A. Kotov and P. E. Savage, A Rapid Hot-Injection Method for the Improved Hydrothermal Synthesis of CdSe Nanoparticles [J]. Ind. Eng. Chem. Res. 2009, 48 (9), 4316-4321.; I. Sondi, O. Siiman, S. Koester and E . Matijevic, Preparation of aminodextran-CdS nanoparticle complexes and biologically active antibody-aminodextran-CdS nanoparticle conjugates [J]. Langmuir. 2000, 16, 3107-3118.). The hot injection method uses a high-boiling-point solvent to quickly inject the precursor reactant solution into another reactant solution at a higher reaction temperature, which is easy to synthesize small-sized nanocrystalline materials with zero defects and easy-to-control morphology.

Iron tetrasulfide is a multi-purpose functional material. Due to the variability of Fe:S ratio in the process of synthesizing iron sulfide, it is difficult to synthesize pure phase iron tetrasulfide (gregite), usually accompanied by two Production of ferrous sulfide. Although there are also studies on the synthesis of ferric sulfide in the current literature reports, the phase purity is generally poor, and most of them contain other sulfur iron compounds. At the same time, the morphology of ferric sulfide is also difficult to control in the reported synthesis process, and it is difficult to obtain ferric ferric sulfide nanocrystals with uniform size, regular shape and controllable shape. At present, there is no report on the preparation method of monodisperse, single phase, uniform size and controllable morphology of ferric iron tetrasulfide nano single crystal.

Contents of the invention

The technical problem to be solved by the present invention is to provide a method for preparing a sheet-shaped iron tetrasulfide nano single crystal with low cost and simple process.

In order to solve the above problems, the preparation method of a kind of flaky iron tetrasulfide nano single crystal of the present invention comprises the following steps:

⑴Mix the iron source and trioctylphosphine oxide (TOPO) at a molar ratio of 1:1.5~1:3, dissolve in oleylamine, stir and pass nitrogen or argon with a purity of more than 98.5% to remove oxygen , to obtain an iron source precursor; the mass volume ratio of the iron source to the oleylamine is 1:50 to 1:150;

(2) heating the iron source precursor to 120-170°C in an oil bath and stirring for 0.5-1.5 hours to obtain an iron source solution;

(3) Dissolving the sulfur source in oleylamine, stirring and passing argon or nitrogen with a purity of more than 98.5% to remove oxygen, to obtain a sulfur source solution; the mass volume ratio of the sulfur source to the oleylamine is 1:50 ~1:100;

(4) Heating the sulfur source solution to 60-90°C, then extracting it with a needle, injecting it quickly into the iron source solution, then raising the temperature of the oil bath for heating the iron source to 190-250°C and reacting for 1-3 hours to obtain Colloid of flaky ferric iron tetrasulfide nano single crystal; the volume ratio of the sulfur source solution to the iron source solution is 1:2 to 1:4;

(5) When the colloid of the flake-shaped iron tetrasulfide nano single crystal is cooled to room temperature, add chloroform-ethanol mixed solution for repeated washing and centrifugation until the upper layer of centrifuged liquid is colorless, and the flake single-phase tetrasulfide Triiron nano single crystal; the volume ratio of trichloromethane and ethanol in the trichloromethane-ethanol mixed solution is 1:0.5~1:1; the colloid of the flake ferric tetrasulfide nano single crystal and the The volume ratio of chloroform-ethanol mixture is 1:2~1:5.

The iron source in the step (1) refers to any one of ferrous chloride, ferric nitrate, and iron acetylacetonate whose concentration is 0.05 ~ 0.5 mol/L.

The sulfur source in the step (3) refers to sulfur powder or thiourea.

In the step (5), the mass concentration of ethanol in the chloroform-ethanol mixture is 50%.

Compared with the prior art, the present invention has the following advantages:

1. The present invention does not need complicated steps, does not use highly toxic solvents such as benzene, but uses a high boiling point solvent - oleylamine, and by selecting different sulfur sources and iron sources, the phase purity of the product can be controlled, so that the iron in the crystal structure The sulfur ratio is an ideal stoichiometric ratio (3:4), and it is a single-phase iron tetrasulfide without pyrite, siderite and other impurity phases.

2. The raw materials used in the present invention are cheap, therefore, the production cost is greatly reduced.

3. Compared with the existing wet chemical method, the preparation method of the present invention has a simple and convenient preparation process, and the synthesized product is a monodisperse sheet-like nano single crystal material with high phase purity, regular shape and uniform size, and the particle size of the synthesized product is the same as The advantages of controllable shape and so on.

4. The X-ray diffraction analysis of the product obtained by the method of the present invention shows that it is a single-phase ferric tetrasulfide (greigite) (see Fig. 1, Fig. 4, Fig. 8), which is different from the standard PDF of ferric tetrasulfide (gregite). The peaks of cards 42-1340 are in perfect agreement.

5. The hysteresis loop (VSM) test of the product obtained by the method of the present invention shows that (see Fig. 7 and Fig. 12), the obtained product is a good ferromagnetic material, and the triangular plate-shaped single-phase iron tetrasulfide nanocrystal is saturated The magnetization (Ms) is 17.07 emu/g, the residual magnetization (Mr) is 7.303 emu/g, and the coercive force (Hc) is 296.02 Oe; the triangular and strip-shaped mixed sheet-like single-phase iron tetrasulfide nanocrystals are saturated The magnetization is 19.05emu/g, the residual magnetization is 5.909 emu/g, and the coercive force is 150.332 Oe; the saturation magnetization (Ms) of the sheet-like intercalated single-phase iron tetrasulfide is 29.02 emu/g, and the residual magnetization (Mr) is 16.51 emu/g, coercivity (Hc) is 566.79 Oe.

6. The product obtained by adopting the method of the present invention is tested by X-ray diffraction, and it can be found that the prepared product is single-phase iron tetrasulfide (see Fig. 1, Fig. 4, Fig. 8).

7. The product obtained by the method of the present invention is tested by transmission electron microscope and scanning electron microscope, and it can be found that the prepared product is monodisperse, regular in appearance, and relatively uniform sheet-like iron tetrasulfide nano single crystal (see Fig. 2 and Fig. 3 ). , Figure 5, Figure 6, Figure 9, Figure 10, Figure 11).

8. The product obtained in the present invention has uniform particle size and shape, good process repeatability, and stable quality, and is expected to be used in medical fields such as cancer hyperthermia therapy and targeted drug delivery medium.

Description of drawings

The specific implementation manners of the present invention will be further described in detail below in conjunction with the accompanying drawings.

Fig. 1 is the X-ray diffraction spectrum of the triangular monolithic single-phase iron tetrasulfide nanocrystal of the present invention.

Fig. 2 is a transmission electron micrograph of a triangular monolithic single-phase iron tetrasulfide nanocrystal of the present invention (the scale bar in the figure is 100nm).

Fig. 3 is a transmission electron micrograph of a triangular monolithic single-phase iron tetrasulfide nanocrystal of the present invention (the scale bar in the figure is 20nm).

Fig. 4 is the X-ray diffraction spectrum of the triangular and strip-shaped mixed flaky single-phase iron tetrasulfide nanocrystals of the present invention.

Fig. 5 is a transmission electron micrograph of a triangular and strip-shaped mixed flake-shaped single-phase iron tetrasulfide nanocrystal of the present invention (the scale bar in the figure is 100nm).

Fig. 6 is a transmission electron micrograph of a triangular and strip-shaped mixed flake-shaped single-phase iron tetrasulfide nanocrystal of the present invention (the scale bar in the figure is 20nm).

Fig. 7 is the VSM diagram of triangular monolithic and triangular and strip-shaped mixed flaky single-phase iron tetrasulfide nanocrystals of the present invention (a-triangular monolithic b-mixed flaky).

Fig. 8 is the X-ray diffraction spectrum of the sheet-like intercalation single-phase iron tetrasulfide nanocrystal of the present invention.

Fig. 9 is a scanning electron micrograph of a sheet-like intercalated single-phase iron tetrasulfide nanocrystal of the present invention (the scale bar in the figure is 200nm).

Fig. 10 is a transmission electron micrograph of a sheet-like intercalated single-phase iron tetrasulfide nanocrystal of the present invention (the scale bar in the figure is 0.5 μm).

Fig. 11 is a transmission electron micrograph of a sheet-like intercalated single-phase iron tetrasulfide nanocrystal of the present invention (the scale bar in the figure is 100nm).

Fig. 12 is a VSM diagram of a sheet-like intercalation single-phase iron tetrasulfide nanocrystal of the present invention.

Detailed ways

Embodiment 1 A kind of preparation method of flaky iron tetrasulfide nanometer single crystal, comprises the following steps:

⑴Mix the iron source—ferrous chloride with a concentration of 0.05mol/L and trioctylphosphine oxide (TOPO) at a molar ratio of 1:1.5, and dissolve in oleylamine, stir and pass the purity to 98.5% After removing oxygen from the above nitrogen or argon gas, an iron source precursor is obtained.

Among them: the mass volume ratio (g/ml) of iron source and oleylamine is 1:50.

(2) Heating the iron source precursor to 120° C. in an oil bath and stirring for 1.5 hours to obtain an iron source solution.

(3) Dissolve the sulfur source—sulfur powder in oleylamine, and after stirring and passing argon or nitrogen with a purity of more than 98.5% to remove oxygen, obtain a sulfur source solution.

Among them: the mass volume ratio (g/ml) of sulfur source and oleylamine is 1:50.

(4) Heating the sulfur source solution to 60°C, then extracting it with a needle tube, quickly injecting it into the iron source solution, and then raising the temperature of the oil bath for heating the iron source to 190°C for 3 hours to obtain flaky iron tetrasulfide nano single crystal colloid.

Among them: the volume ratio of sulfur source solution to iron source solution (ml/ml) is 1:2.

(5) When the colloid of flaky ferric iron tetrasulfide nano single crystal is cooled to room temperature, add chloroform-ethanol mixed solution for repeated washing and centrifugation until the upper layer of centrifuged liquid is colorless, that is, flake single phase ferric ferric sulfide Nano single crystal.

Among them: the volume ratio (ml/ml) of chloroform to ethanol in the chloroform-ethanol mixture is 1:0.5; The ratio (ml/ml) is 1:2; the mass concentration of ethanol in the chloroform-ethanol mixture is 50%.

Embodiment 2 A kind of preparation method of flaky iron tetrasulfide nanometer single crystal, comprises the following steps:

⑴Mix the iron source—ferrous chloride with a concentration of 0.5 mol/L and trioctylphosphine oxide (TOPO) at a molar ratio of 1:3, and dissolve it in oleylamine, stir and pass the purity to 98.5% After removing oxygen from the above nitrogen or argon gas, an iron source precursor is obtained.

Among them: the mass volume ratio (g/ml) of iron source and oleylamine is 1:150.

(2) Heating the iron source precursor to 170° C. in an oil bath and stirring for 0.5 hours to obtain an iron source solution.

(3) Dissolve the sulfur source—thiourea in oleylamine, and after stirring and passing argon or nitrogen with a purity of more than 98.5% to remove oxygen, obtain a sulfur source solution.

Among them: the mass volume ratio (g/ml) of sulfur source to oleylamine is 1:100.

(4) Heating the sulfur source solution to 90°C, then extracting it with a needle tube, quickly injecting it into the iron source solution, and then raising the temperature of the oil bath for heating the iron source to 250°C for 1 hour to obtain flaky iron tetrasulfide nano single crystal colloid.

Among them: the volume ratio of sulfur source solution to iron source solution (ml/ml) is 1:4.

(5) When the colloid of flaky ferric iron tetrasulfide nano single crystal is cooled to room temperature, add chloroform-ethanol mixed solution for repeated washing and centrifugation until the upper layer of centrifuged liquid is colorless, that is, flake single phase ferric ferric sulfide Nano single crystal.

Among them: the volume ratio (ml/ml) of chloroform and ethanol in the chloroform-ethanol mixture is 1:1; The ratio (ml/ml) is 1:5; the mass concentration of ethanol in the chloroform-ethanol mixture is 50%.

Embodiment 3 A kind of preparation method of flaky iron tetrasulfide nanometer single crystal, comprises the following steps:

⑴Mix the iron source—ferrous chloride with a concentration of 0.25 mol/L and trioctylphosphine oxide (TOPO) at a molar ratio of 1:2.5, dissolve in oleylamine, stir and pass the purity to 98.5% After removing oxygen from the above nitrogen or argon gas, an iron source precursor is obtained.

Among them: the mass volume ratio (g/ml) of iron source and oleylamine is 1:100.

(2) Heating the iron source precursor to 150° C. in an oil bath and stirring for 1 hour to obtain an iron source solution.

(3) Dissolve the sulfur source—sulfur powder in oleylamine, and after stirring and passing argon or nitrogen with a purity of more than 98.5% to remove oxygen, obtain a sulfur source solution.

Among them: the mass volume ratio (g/ml) of sulfur source to oleylamine is 1:75.

(4) Heating the sulfur source solution to 80°C, then extracting it with a needle, quickly injecting it into the iron source solution, and then raising the temperature of the oil bath for heating the iron source to 220°C and reacting for 2 hours to obtain flaky iron tetrasulfide nano single crystal colloid.

Among them: the volume ratio of sulfur source solution to iron source solution (ml/ml) is 1:3.

(5) When the colloid of flaky ferric iron tetrasulfide nano single crystal is cooled to room temperature, add chloroform-ethanol mixed solution for repeated washing and centrifugation until the upper layer of centrifuged liquid is colorless, that is, flake single phase ferric ferric sulfide Nano single crystal.

Among them: the volume ratio (ml/ml) of chloroform to ethanol in the chloroform-ethanol mixture is 1:0.75; The ratio (ml/ml) is 1:3.5; the mass concentration of ethanol in the chloroform-ethanol mixture is 50%.

Embodiment 4 A kind of preparation method of flaky iron tetrasulfide nanometer single crystal comprises the following steps:

⑴Mix the iron source—ferric nitrate with a concentration of 0.05mol/L and trioctylphosphine oxide (TOPO) at a molar ratio of 1:1.5, dissolve in oleylamine, stir and pass through the After oxygen is removed by nitrogen or argon, the iron source precursor is obtained.

Among them: the mass volume ratio (g/ml) of iron source and oleylamine is 1:50.

(2) Heating the iron source precursor to 120° C. in an oil bath and stirring for 1.5 hours to obtain an iron source solution.

(3) Dissolve the sulfur source—thiourea in oleylamine, and after stirring and passing argon or nitrogen with a purity of more than 98.5% to remove oxygen, obtain a sulfur source solution.

Among them: the mass volume ratio (g/ml) of sulfur source and oleylamine is 1:50.

(4) Heating the sulfur source solution to 60°C, then extracting it with a needle tube, quickly injecting it into the iron source solution, and then raising the temperature of the oil bath for heating the iron source to 190°C for 3 hours to obtain flaky iron tetrasulfide nano single crystal colloid.

Among them: the volume ratio of sulfur source solution to iron source solution (ml/ml) is 1:2.

(5) When the colloid of flaky ferric iron tetrasulfide nano single crystal is cooled to room temperature, add chloroform-ethanol mixed solution for repeated washing and centrifugation until the upper layer of centrifuged liquid is colorless, that is, flake single phase ferric ferric sulfide Nano single crystal.

Among them: the volume ratio (ml/ml) of chloroform to ethanol in the chloroform-ethanol mixture is 1:0.5; The ratio (ml/ml) is 1:2; the mass concentration of ethanol in the chloroform-ethanol mixture is 50%.

Embodiment 5 A kind of preparation method of flaky ferric iron tetrasulfide nanometer single crystal, comprises the following steps:

⑴Mix the iron source—ferric nitrate with a concentration of 0.5 mol/L and trioctylphosphine oxide (TOPO) at a molar ratio of 1:3, and dissolve it in oleylamine, stir and pass through the product with a purity of more than 98.5%. After oxygen is removed by nitrogen or argon, the iron source precursor is obtained.

Among them: the mass volume ratio (g/ml) of iron source and oleylamine is 1:150.

(2) Heating the iron source precursor to 170° C. in an oil bath and stirring for 0.5 hours to obtain an iron source solution.

(3) Dissolve the sulfur source—sulfur powder in oleylamine, and after stirring and passing argon or nitrogen with a purity of more than 98.5% to remove oxygen, obtain a sulfur source solution.

Among them: the mass volume ratio (g/ml) of sulfur source to oleylamine is 1:100.

(4) Heating the sulfur source solution to 90°C, then extracting it with a needle tube, quickly injecting it into the iron source solution, and then raising the temperature of the oil bath for heating the iron source to 250°C for 1 hour to obtain flaky iron tetrasulfide nano single crystal colloid.

Among them: the volume ratio of sulfur source solution to iron source solution (ml/ml) is 1:4.

(5) When the colloid of flaky ferric iron tetrasulfide nano single crystal is cooled to room temperature, add chloroform-ethanol mixed solution for repeated washing and centrifugation until the upper layer of centrifuged liquid is colorless, that is, flake single phase ferric ferric sulfide Nano single crystal.

Among them: the volume ratio (ml/ml) of chloroform and ethanol in the chloroform-ethanol mixture is 1:1; The ratio (ml/ml) is 1:5; the mass concentration of ethanol in the chloroform-ethanol mixture is 50%.

Embodiment 6 A kind of preparation method of flaky iron tetrasulfide nanometer single crystal, comprises the following steps:

⑴Mix the iron source—ferric nitrate with a concentration of 0.2 mol/L and trioctylphosphorus oxide (TOPO) at a molar ratio of 1:2, and dissolve in oleylamine, stir and pass through the After oxygen is removed by nitrogen or argon, the iron source precursor is obtained.

Among them: the mass volume ratio (g/ml) of iron source and oleylamine is 1:100.

(2) Heating the iron source precursor to 150° C. in an oil bath and stirring for 1 hour to obtain an iron source solution.

(3) Dissolve the sulfur source—thiourea in oleylamine, and after stirring and passing argon or nitrogen with a purity of more than 98.5% to remove oxygen, obtain a sulfur source solution.

Among them: the mass volume ratio (g/ml) of sulfur source and oleylamine is 1:80.

(4) Heating the sulfur source solution to 70°C, then extracting it with a needle tube, quickly injecting it into the iron source solution, and then raising the temperature of the oil bath for heating the iron source to 200°C for 2 hours to obtain flaky iron tetrasulfide nano single crystal colloid.

Among them: the volume ratio of sulfur source solution to iron source solution (ml/ml) is 1:3.

(5) When the colloid of flaky ferric iron tetrasulfide nano single crystal is cooled to room temperature, add chloroform-ethanol mixed solution for repeated washing and centrifugation until the upper layer of centrifuged liquid is colorless, that is, flake single phase ferric ferric sulfide Nano single crystal.

Among them: the volume ratio (ml/ml) of chloroform to ethanol in the chloroform-ethanol mixture is 1:0.65; The ratio (ml/ml) is 1:3; the mass concentration of ethanol in the chloroform-ethanol mixture is 50%.

Embodiment 7 A kind of preparation method of flaky iron tetrasulfide nano single crystal, comprises the following steps:

⑴Mix the iron source—iron acetylacetonate with a concentration of 0.05mol/L and trioctylphosphine oxide (TOPO) at a molar ratio of 1:1.5, and dissolve it in oleylamine, stir and pass the purity to more than 98.5% After removing oxygen from nitrogen or argon, the iron source precursor is obtained.

Among them: the mass volume ratio (g/ml) of iron source and oleylamine is 1:50.

(2) Heating the iron source precursor to 120° C. in an oil bath and stirring for 1.5 hours to obtain an iron source solution.

(3) Dissolve the sulfur source—thiourea in oleylamine, and after stirring and passing argon or nitrogen with a purity of more than 98.5% to remove oxygen, a sulfur source solution is obtained.

Among them: the mass volume ratio (g/ml) of sulfur source and oleylamine is 1:50.

(4) Heating the sulfur source solution to 60°C, then extracting it with a needle tube, quickly injecting it into the iron source solution, and then raising the temperature of the oil bath for heating the iron source to 190°C for 3 hours to obtain flaky iron tetrasulfide nano single crystal colloid.

Among them: the volume ratio of sulfur source solution to iron source solution (ml/ml) is 1:2.

(5) When the colloid of flaky ferric iron tetrasulfide nano single crystal is cooled to room temperature, add chloroform-ethanol mixed solution for repeated washing and centrifugation until the upper layer of centrifuged liquid is colorless, that is, flake single phase ferric ferric sulfide Nano single crystal.

Among them: the volume ratio (ml/ml) of chloroform to ethanol in the chloroform-ethanol mixture is 1:0.5; The ratio (ml/ml) is 1:2; the mass concentration of ethanol in the chloroform-ethanol mixture is 50%.

Embodiment 8 A kind of preparation method of flaky ferric iron tetrasulfide nanometer single crystal, comprises the following steps:

⑴Mix the iron source—iron acetylacetonate with a concentration of 0.5 mol/L and trioctylphosphine oxide (TOPO) at a molar ratio of 1:3, and dissolve it in oleylamine. After stirring, the purity is above 98.5%. After removing oxygen from nitrogen or argon, the iron source precursor is obtained.

Among them: the mass volume ratio (g/ml) of iron source and oleylamine is 1:150.

(2) Heating the iron source precursor to 170° C. in an oil bath and stirring for 0.5 hours to obtain an iron source solution.

(3) Dissolve the sulfur source—sulfur powder in oleylamine, and after stirring and passing argon or nitrogen with a purity of more than 98.5% to remove oxygen, obtain a sulfur source solution.

Among them: the mass volume ratio (g/ml) of sulfur source to oleylamine is 1:100.

(4) Heating the sulfur source solution to 90°C, then extracting it with a needle tube, quickly injecting it into the iron source solution, and then raising the temperature of the oil bath for heating the iron source to 250°C for 1 hour to obtain flaky iron tetrasulfide nano single crystal colloid.

Among them: the volume ratio of sulfur source solution to iron source solution (ml/ml) is 1:4.

(5) When the colloid of flake-shaped iron tetrasulfide nano single crystal is cooled to room temperature, add chloroform-ethanol mixed solution for repeated washing and centrifugation until the upper layer of centrifuged liquid is colorless, and the flake single-phase iron tetrasulfide is obtained Nano single crystal.

Among them: the volume ratio (ml/ml) of chloroform and ethanol in the chloroform-ethanol mixture is 1:1; The ratio (ml/ml) is 1:5; the mass concentration of ethanol in the chloroform-ethanol mixture is 50%.

Embodiment 9 A kind of preparation method of flake iron ferric sulfide nanometer single crystal, comprises the following steps:

⑴Mix the iron source—iron acetylacetonate with a concentration of 0.3 mol/L and trioctylphosphine oxide (TOPO) at a molar ratio of 1:2.5, dissolve in oleylamine, stir and pass the purity to 98.5% or more After removing oxygen from nitrogen or argon, the iron source precursor is obtained.

Among them: the mass volume ratio (g/ml) of iron source and oleylamine is 1:125.

(2) Heating the iron source precursor to 155° C. in an oil bath and stirring for 1 hour to obtain an iron source solution.

(3) Dissolve the sulfur source—thiourea in oleylamine, and after stirring and passing argon or nitrogen with a purity of more than 98.5% to remove oxygen, obtain a sulfur source solution.

Among them: the mass volume ratio (g/ml) of sulfur source to oleylamine is 1:85.

(4) Heating the sulfur source solution to 70°C, then extracting it with a needle, quickly injecting it into the iron source solution, and then raising the temperature of the oil bath heating the iron source to 200°C for 1.5 hours to obtain flaky iron tetrasulfide nano single crystal colloid.

Among them: the volume ratio of sulfur source solution to iron source solution (ml/ml) is 1:3.5.

(5) When the colloid of flaky ferric iron tetrasulfide nano single crystal is cooled to room temperature, add chloroform-ethanol mixed solution for repeated washing and centrifugation until the upper layer of centrifuged liquid is colorless, that is, flake single phase ferric ferric sulfide Nano single crystal.

Among them: the volume ratio (ml/ml) of chloroform to ethanol in the chloroform-ethanol mixture is 1:0.9; The ratio (ml/ml) is 1:4; the mass concentration of ethanol in the chloroform-ethanol mixture is 50%.

Claims (1)

1. a preparation method for flaky iron sulfide single crystal nano-material, comprises the following steps:

(1) source of iron and trioctylphosphine oxide are pressed the mixed in molar ratio of 1:1.5 ~ 1:3, and are dissolved in oleyl amine, through stir and logical purity be more than 98.5% nitrogen or argon gas removing oxygen after, obtain source of iron presoma; The mass volume ratio of described source of iron and described oleyl amine is 1:50 ~ 1:150; Described source of iron refers to that concentration is any one in the iron protochloride of 0.05 ~ 0.5 mol/L, iron nitrate, ferric acetyl acetonade;

(2) described source of iron presoma be heated to 120 ~ 170 DEG C in oil bath and stir 0.5 ~ 1.5 hour, obtaining source of iron solution;

(3) sulphur source is dissolved in oleyl amine, through stir and logical purity be more than 98.5% argon gas or nitrogen removing oxygen after, obtain sulphur source solution; The mass volume ratio of described sulphur source and described oleyl amine is 1:50 ~ 1:100; Described sulphur source refers to sulphur powder or thiocarbamide;

(4) described sulphur source solution is heated to 60 ~ 90 DEG C, then extract with needle tubing, fast injection is entered in source of iron solution, then the oil bath of described heating source of iron is warming up to 190 ~ 250 DEG C of reactions 1 ~ 3 hour, obtains the colloid of flaky iron sulfide single crystal nano-material; The volume ratio of described sulphur source solution and described source of iron solution is 1:2 ~ 1:4;

(5) when the colloid of described flaky iron sulfide single crystal nano-material being cooled to room temperature, add that trichloromethane-alcohol mixeding liquid repeatedly washs, centrifugal treating until upper strata centrifugate is colourless, obtain sheet single-phase iron sulfide single crystal nano-material; Trichloromethane in described trichloromethane-alcohol mixeding liquid and the volume ratio of ethanol are 1:0.5 ~ 1:1; The colloid of described flaky iron sulfide single crystal nano-material and the volume ratio of described trichloromethane-alcohol mixeding liquid are 1:2 ~ 1:5; In described trichloromethane-alcohol mixeding liquid, the mass concentration of ethanol is 50%.