CN107934926A - A kind of preparation method of two selenizings molybdenum nanotube - Google Patents

Abstract

The invention discloses a method for preparing molybdenum diselenide nanotubes, which comprises the following process steps: 1) laying molybdenum hexacarbonyl on the bottom of a ceramic crucible, and then placing the opening of a porous anodized aluminum template downward on the molybdenum hexacarbonyl Above, seal the crucible and place it in a tube furnace, sublimation deposition at low temperature under gas protection, and continue to heat up pyrolysis; 2) After the vacuum tube furnace drops to room temperature, place the template opening downwards in a ceramic crucible filled with selenium powder, After sealing the crucible, the temperature is raised to make the elemental selenium react directly with metal molybdenum; 3) remove the porous alumina template and excess selenium with dilute acid solution, and then carry out suction filtration and drying to obtain the finished product. The method of the invention has simple steps, no environmental pollution, and no need for complicated equipment. The prepared molybdenum diselenide nanotube powder material has strong size controllability, good crystallinity, and uniform nanotube wall shape, thereby greatly improving The comprehensive performance of the finished product of the molybdenum diselenide nanotube powder material. The invention has wide applicability and is beneficial to large-scale industrial production.

Description

A kind of preparation method of molybdenum diselenide nanotube

technical field

The invention relates to the field of semiconductor nanomaterials, in particular to a method for preparing semiconductor nanotubes.

Background technique

Two-dimensional semiconductor materials have been studied more and more because of their inherent large band gap. But for graphene, although it has great research value in electronics because of its remarkable carrier mobility, its application in optoelectronics is greatly limited due to the lack of band gap. Molybdenum diselenide is a transition metal selenide with a two-dimensional layered structure with a band gap. It is stacked by sandwich units composed of hexagonal X-M-X. Metal elements and selenium elements are combined into a single sandwich by covalent bonds unit, and different units are joined by weak van der Waals forces. This unique energy band structure determines that they have abundant electronic states, making them very suitable for applications in electronics, photonics and other fields. In addition, the molybdenum diselenide single-layer sheet has a three-dimensional porous structure and has good structural rigidity, which can significantly improve the thermal and mechanical properties of the device. Therefore, two-dimensional molybdenum diselenide crystals will have broad application prospects in the fields of solar cells, photocatalysts, phototransistors, light-emitting diodes, and light modulators. The current research reports mainly focus on the preparation and performance research of multilayer molybdenum diselenide, and there are few studies on one-dimensional materials, especially the preparation method.

Contents of the invention

The object of the present invention is to provide a method for preparing molybdenum diselenide nanotubes in view of the deficiencies in the prior art above. Electronic devices.

The technical solution adopted by the present invention is: a preparation method of molybdenum diselenide nanotubes, which comprises the following process steps:

1) Using molybdenum hexacarbonyl as raw material and porous anodized alumina as a template, the raw material is paved on the bottom of the ceramic crucible, and then the porous anodized aluminum template is placed on the raw material with the opening downward, and the crucible is sealed and placed in a vacuum tube furnace. Heating under gas protection, sublimation at low temperature, sublimates and deposits molybdenum hexacarbonyl in the porous anodized aluminum template, and continues to raise the temperature to thermally decompose the molybdenum hexacarbonyl deposited in the porous anodized aluminum template to obtain metal molybdenum deposition;

2) After the vacuum tube furnace in step 1) is down to room temperature, take out the alumina template, place its opening downwards in a ceramic crucible filled with selenium powder, place it in a vacuum tube furnace after sealing the crucible, and place it under gas protection Lower the temperature to make the elemental selenium react directly with metal molybdenum, stop heating, and cool the crucible to room temperature with the furnace;

3) Remove the porous alumina template and excess selenium with a dilute acid solution, wash with deionized water, perform suction filtration, and dry to obtain a finished product.

As a further improvement of the above solution, the pore diameter of the porous anodized alumina template described in step 1) is in the range of 10-200 nm. Specifically, the limitation of the pore size of the porous anodized aluminum template in the present invention can make the shape of the nanotubes more controllable.

As a further improvement of the above scheme, the temperature of the low-temperature sublimation described in step 1) is 50-150° C., and the sublimation time is 30-200 min. The present invention directly obtains deposits through low-temperature sublimation, and the limitation of sublimation temperature and holding time can make molybdenum hexacarbonyl deposit more fully.

As a further improvement of the above solution, the thermal decomposition temperature in step 1) is 200-420° C., and the thermal decomposition time is 30-100 min. Specifically, the limitation of the pyrolysis temperature and pyrolysis time in the present invention can effectively improve the crystallinity of metal molybdenum in the alumina template.

As a further improvement of the above scheme, the reaction temperature of elemental selenium and metal molybdenum in step 2) is 500-750° C., and the reaction time is 30-120 min. Specifically, the limitation of the reaction temperature and time of molybdenum diselenide in the present invention can make the reaction more complete.

As a further improvement of the above solution, the dilute acid solution in step 3) is a phosphoric acid solution with a concentration of 0.1-3 mol/L. Specifically, further confinement of the dilute acid solution allows for more efficient removal of the alumina template.

As a further improvement of the above scheme, the gas described in step 1) and step 2) is argon or nitrogen, the gas purity is 99.999%, and the gas flow rate of the gas protection is 10-500 SCCM.

The beneficial effects of the present invention are: the method of the present invention has simple steps, realizes the direct reaction of metal molybdenum and selenium powder in a confined space to prepare a molybdenum diselenide nanotube powder material, which has no environmental pollution and does not require complicated equipment. The prepared molybdenum diselenide nanotube powder material has strong size controllability, good crystallinity, and uniform nanotube wall shape, thereby greatly improving the comprehensive performance of the finished product of the molybdenum diselenide nanotube powder material. The invention has wide applicability and is beneficial to large-scale industrial production.

Detailed ways

The present invention will be specifically described below in conjunction with the embodiments, so that those skilled in the art can understand the present invention. It is necessary to point out here that the embodiments are only used to further illustrate the present invention, and cannot be interpreted as limiting the protection scope of the present invention. Those skilled in the art can make non-essential improvements and improvements to the present invention according to the above-mentioned content of the invention. Adjustment should still belong to the protection scope of the present invention. At the same time, if the raw materials mentioned below are not specified in detail, they are all commercially available products; the process steps or preparation methods not mentioned in detail are all process steps or preparation methods known to those skilled in the art.

Example 1

A preparation method for molybdenum diselenide nanotubes, comprising the following process steps:

1) Spread 5g of molybdenum hexacarbonyl on the bottom of a ceramic crucible, place a porous anodized aluminum template with a pore diameter of 40nm downwards on top of the molybdenum hexacarbonyl, seal the crucible and place it in a vacuum tube furnace, and feed it with 100 SCCM of argon Gas cleaning of the air in the furnace tubes. Under the protection of 100SCCM argon gas, raise the temperature to 100°C and keep it for 60 minutes, then continue to raise the temperature to 300°C and keep it for 40 minutes to get metal molybdenum deposition, stop heating;

2) After the vacuum tube furnace in step 1) is down to room temperature, take out the porous anodized aluminum template, place its opening downwards in a ceramic crucible filled with selenium powder, seal the crucible and place it in a vacuum tube furnace, Under the protection of 100SCCM argon gas, heat up to 250°C and keep it for 60 minutes, continue to heat up to 650°C and keep it for 90 minutes, then stop heating;

3) When the temperature of the ceramic crucible in step 2) drops to room temperature, take out the sample, remove the porous alumina template and excess selenium powder with a phosphoric acid solution with a concentration of 0.3mol/L, wash with deionized water, and then carry out suction filtration and drying Dry to obtain the finished product of molybdenum diselenide nanotube powder material in Example 1.

Example 2

A preparation method for molybdenum diselenide nanotubes, comprising the following process steps:

1) Spread 5g of molybdenum hexacarbonyl on the bottom of a ceramic crucible, place a porous anodized aluminum template with a pore size of 10nm downwards on top of the molybdenum hexacarbonyl, seal the crucible and place it in a vacuum tube furnace, and pass it into 100SCCM of argon Gas cleaning of the air in the furnace tubes. Under the protection of 100SCCM argon gas, raise the temperature to 50°C and keep it for 200min, then continue to raise the temperature to 300°C and keep it for 40min to get metal molybdenum deposition, stop heating;

2) After the vacuum tube furnace in step 1) is down to room temperature, take out the porous anodized aluminum template, place its opening downwards in a ceramic crucible filled with selenium powder, seal the crucible and place it in a vacuum tube furnace, Under the protection of 100SCCM argon gas, heat up to 220°C and keep it for 60 minutes, continue to heat up to 550°C and keep it for 120 minutes, then stop heating;

3) When the temperature of the ceramic crucible in step 2) drops to room temperature, take out the sample, remove the porous alumina template and excess selenium powder with a phosphoric acid solution with a concentration of 0.3mol/L, wash with deionized water, and then carry out suction filtration and drying Dry to obtain the finished product of the molybdenum diselenide nanotube powder material of Example 2.

Example 3

A preparation method for molybdenum diselenide nanotubes, comprising the following process steps:

1) Spread 5g of molybdenum hexacarbonyl on the bottom of a ceramic crucible, place a porous anodized aluminum template with a pore size of 200nm downwards on top of the molybdenum hexacarbonyl, seal the crucible and place it in a vacuum tube furnace, and feed it with 100 SCCM of argon Gas cleaning of the air in the furnace tubes. Under the protection of 100SCCM argon gas, raise the temperature to 150°C and keep it for 30 minutes, then continue to raise the temperature to 300°C and keep it for 40 minutes to get metal molybdenum deposition, stop heating;

2) After the vacuum tube furnace in step 1) is down to room temperature, take out the porous anodized aluminum template, place its opening downwards in a ceramic crucible filled with selenium powder, seal the crucible and place it in a vacuum tube furnace, Under the protection of 100SCCM argon gas, heat up to 220°C and keep it for 60 minutes, continue to heat up to 550°C and keep it for 120 minutes, then stop heating;

3) When the temperature of the ceramic crucible in step 2) drops to room temperature, take out the sample, remove the porous alumina template and excess selenium powder with a phosphoric acid solution with a concentration of 0.1mol/L, wash it with deionized water, and then carry out suction filtration and drying Dry to obtain the finished product of the molybdenum diselenide nanotube powder material of Example 3.

Example 4

A preparation method for molybdenum diselenide nanotubes, comprising the following process steps:

1) Spread 5g of molybdenum hexacarbonyl on the bottom of a ceramic crucible, place a porous anodized aluminum template with a pore diameter of 40nm downwards on top of the molybdenum hexacarbonyl, seal the crucible and place it in a vacuum tube furnace, and feed in 100 SCCM of nitrogen Purge air from furnace tubes. Under the protection of nitrogen at 100SCCM, raise the temperature to 100°C and keep it for 60 minutes, then continue to raise the temperature to 200°C and keep it for 100 minutes to get molybdenum metal deposition, stop heating;

2) After the vacuum tube furnace in step 1) is down to room temperature, take out the porous anodized aluminum template, place its opening downwards in a ceramic crucible filled with selenium powder, seal the crucible and place it in a vacuum tube furnace, Under the protection of 100SCCM nitrogen, raise the temperature to 220°C and keep it for 60 minutes, continue to raise the temperature to 550°C and keep it for 120 minutes, then stop heating;

3) When the temperature of the ceramic crucible in step 2) drops to room temperature, take out the sample, remove the porous alumina template and excess selenium powder with a phosphoric acid solution with a concentration of 3mol/L, wash with deionized water, perform suction filtration, and dry , to obtain the finished product of molybdenum diselenide nanotube powder material in Example 4.

Example 5

A preparation method for molybdenum diselenide nanotubes, comprising the following process steps:

1) Spread 5g of molybdenum hexacarbonyl on the bottom of a ceramic crucible, place a porous anodized aluminum template with a pore diameter of 40nm downwards on top of the molybdenum hexacarbonyl, seal the crucible and place it in a vacuum tube furnace, and feed it with 100 SCCM of argon Gas cleaning of the air in the furnace tubes. Under the protection of 100SCCM argon gas, raise the temperature to 100°C and keep it for 60 minutes, then continue to raise the temperature to 420°C and keep it for 30 minutes to get metal molybdenum deposition, stop heating;

2) After the vacuum tube furnace in step 1) is down to room temperature, take out the porous anodized aluminum template, place its opening downwards in a ceramic crucible filled with selenium powder, seal the crucible and place it in a vacuum tube furnace, Under the protection of 100SCCM argon gas, heat up to 300°C and keep it for 60 minutes, continue to heat up to 550°C and keep it for 120 minutes, then stop heating;

3) When the temperature of the ceramic crucible in step 2) drops to room temperature, take out the sample, remove the porous alumina template and excess selenium powder with a phosphoric acid solution with a concentration of 0.3mol/L, wash with deionized water, and then carry out suction filtration and drying Dry to obtain the finished product of the molybdenum diselenide nanotube powder material of Example 5.

Example 6

A preparation method for molybdenum diselenide nanotubes, comprising the following process steps:

1) Spread 5g of molybdenum hexacarbonyl on the bottom of a ceramic crucible, place a porous anodized aluminum template with a pore diameter of 40nm downwards on top of the molybdenum hexacarbonyl, seal the crucible and place it in a vacuum tube furnace, and feed it with 100 SCCM of argon Gas cleaning of the air in the furnace tubes. Under the protection of 100SCCM argon gas, raise the temperature to 100°C and keep it for 60 minutes, then continue to raise the temperature to 300°C and keep it for 40 minutes to get metal molybdenum deposition, stop heating;

2) After the vacuum tube furnace in step 1) is down to room temperature, take out the porous anodized aluminum template, place its opening downwards in a ceramic crucible filled with selenium powder, seal the crucible and place it in a vacuum tube furnace, Under the protection of 100SCCM argon gas, heat up to 300°C and keep it for 60 minutes, continue to heat up to 550°C and keep it for 120 minutes, then stop heating;

3) When the temperature of the ceramic crucible in step 2) drops to room temperature, take out the sample, remove the porous alumina template and excess selenium powder with a phosphoric acid solution with a concentration of 0.3mol/L, wash with deionized water, and then carry out suction filtration and drying Dry to obtain the finished product of the molybdenum diselenide nanotube powder material of Example 6.

Example 7

A preparation method for molybdenum diselenide nanotubes, comprising the following process steps:

1) Spread 5g of molybdenum hexacarbonyl on the bottom of a ceramic crucible, place a porous anodized aluminum template with a pore diameter of 40nm downwards on top of the molybdenum hexacarbonyl, seal the crucible and place it in a vacuum tube furnace, and pass it into 10SCCM of argon Gas cleaning of the air in the furnace tubes. Under the protection of 10SCCM argon gas, raise the temperature to 100°C and keep it for 60 minutes, then continue to raise the temperature to 300°C and keep it for 40 minutes to get metal molybdenum deposition, stop heating;

2) After the vacuum tube furnace in step 1) is down to room temperature, take out the porous anodized aluminum template, place its opening downwards in a ceramic crucible filled with selenium powder, seal the crucible and place it in a vacuum tube furnace, Under the protection of 10SCCM of argon gas, the temperature was raised to 220°C and kept for 120min, then the temperature was raised to 500°C and kept for 120min, and then the heating was stopped;

3) When the temperature of the ceramic crucible in step 2) drops to room temperature, take out the sample, remove the porous alumina template and excess selenium powder with a phosphoric acid solution with a concentration of 0.3mol/L, wash with deionized water, and then carry out suction filtration and drying Dry to obtain the finished product of the molybdenum diselenide nanotube powder material of Example 7.

Example 8

A preparation method for molybdenum diselenide nanotubes, comprising the following process steps:

1) Spread 5g of molybdenum hexacarbonyl on the bottom of a ceramic crucible, place a porous anodized aluminum template with a pore diameter of 40nm downwards on top of the molybdenum hexacarbonyl, seal the crucible and place it in a vacuum tube furnace, and pass it into 500SCCM of argon Gas cleaning of the air in the furnace tubes. Under the protection of argon gas at 500SCCM, raise the temperature to 100°C and keep it for 60 minutes, then continue to raise the temperature to 300°C and keep it for 40 minutes to get metal molybdenum deposition, stop heating;

2) After the vacuum tube furnace in step 1) is down to room temperature, take out the porous anodized aluminum template, place its opening downwards in a ceramic crucible filled with selenium powder, seal the crucible and place it in a vacuum tube furnace, Under the protection of 500SCCM argon gas, the temperature was raised to 220°C and kept for 60 minutes, then the temperature was raised to 750°C and kept for 30 minutes, and then the heating was stopped;

3) When the temperature of the ceramic crucible in step 2) drops to room temperature, take out the sample, remove the porous alumina template and excess selenium powder with a phosphoric acid solution with a concentration of 0.3mol/L, wash with deionized water, and then carry out suction filtration and drying Dry to obtain the finished product of the molybdenum diselenide nanotube powder material of Example 8.

Example 9

The finished molybdenum diselenide nanotube powder materials prepared in the above-mentioned Examples 1 to 8 were respectively observed with a scanning electron microscope, and it was observed that they all formed a one-dimensional tubular structure with uniform tube wall morphology and uniform diameter, and their crystallinity was good. , the shape of nanotubes is highly controllable.

The above-mentioned embodiments are preferred embodiments of the present invention, and all processes similar to those of the present invention and equivalent changes should all belong to the protection category of the present invention.

Claims (7)

1. a kind of preparation method of two selenizings molybdenum nanotube, it is characterised in that comprise the technical steps that：

1) using hexacarbonylmolybdenum as raw material, porous anodic aluminium oxide mats formation raw material in ceramic crucible bottom as template, after will Open Side Down is placed in above raw material for porous anodic alumina template, and sealed crucible is placed in vacuum tube furnace, in gas shield Lower heating, low-temperature distillation, makes hexacarbonylmolybdenum be deposited in porous anodic alumina template, continues to heat up, and makes to be deposited on porous sun Hexacarbonylmolybdenum thermal decomposition in the alumina formwork of pole, obtains metal molybdenum deposition；

2) treat that the vacuum tube furnace of step 1) is cooled to room temperature, take out porous anodic alumina template, and Open Side Down puts by it In the ceramic crucible equipped with selenium powder, sealed crucible is placed in vacuum tube furnace, is heated up under gas shield, make elemental selenium with Metal molybdenum is directly reacted, and stops heating after completion of the reaction, and crucible cools to room temperature with the furnace；

3) porous alumina formwork and unnecessary selenium are removed with dilute acid soln, deionized water cleaning, after carry out suction filtration processing, dry It is dry, obtain finished product.

A kind of 2. preparation method of two selenizings molybdenum nanotube according to claim 1, it is characterised in that：Described in step 1) Porous anodic alumina template aperture in the range of 10~200nm.

A kind of 3. preparation method of two selenizings molybdenum nanotube according to claim 1, it is characterised in that：Described in step 1) Low-temperature distillation temperature be 50~150 DEG C, sublimation time is 30~200min.

A kind of 4. preparation method of two selenizings molybdenum nanotube according to claim 1, it is characterised in that：Described in step 1) The temperature of thermal decomposition is 200~420 DEG C, and thermal decomposition time is 30~100min.

A kind of 5. preparation method of two selenizings molybdenum nanotube according to claim 1, it is characterised in that：Described in step 2) The reaction temperature of elemental selenium and metal molybdenum is 500~750 DEG C, and the reaction time is 30~120min.

A kind of 6. preparation method of two selenizings molybdenum nanotube according to claim 1, it is characterised in that：Described in step 3) Dilute acid soln be phosphoric acid solution that concentration is 0.1~3mol/L.

A kind of 7. preparation method of two selenizings molybdenum nanotube according to claim 1, it is characterised in that：Step 1) and step 2) gas described in is argon gas or nitrogen, gas purity 99.999%, the gas flow rate of the gas shield for 10~ 500SCCM。