Method for producing black phosphorus

Abstract

A method of producing black phosphorus which includes the steps of: weighing and mixing reaction raw materials which comprises metallic tin, red phosphorus and monocrystalline iodine, wherein a weight ratio of tin: red phosphorus: iodine is 0.6-3.5: 5-45: 0.1-0.8; feeding the mixture to a high-temperature resistant metal reaction tube; removing air by introducing inert gas and sealing the reaction tube tightly; placing the metal reaction tube inside a muffle furnace for carrying out calcination reaction by first increasing a temperature at a preset rate to a maximum temperature and keeping warm and then decreasing a temperature at a preset rate and keeping warm, then to room temperature so that the black phosphorus is produced. The conversion rate is very high and the quality of the produced product is classified as high quality.

Claims

1. A method of producing black phosphorus, comprising the steps of: (a) weighing reaction raw materials which comprises metallic tin, red phosphorus and monocrystalline iodine, wherein a weight ratio of tin: red phosphorus: iodine is 0.6-3.5: 5-45: 0.1-0.8; (b) mixing the reaction raw materials uniformly to form a mixture; (c) feeding the mixture to a glass tube, replacing air inside the glass tube by inert gas, closing a glass tube opening of the glass tube by a plug and then placing the glass tube inside a high-temperature resistant metal reaction tube; (d) introducing inert gas to the high-temperature resistant metal reaction tube to replace air inside the high-temperature resistant metal reaction tube with the inert gas; (e) closing and sealing the metal reaction tube tightly; and (f) placing the metal reaction tube inside a muffle furnace for carrying out calcination reaction by controlling a temperature increase at a rate 50-80° C./h from room temperature to a first reaction temperature, a second reaction temperature and then a third reaction temperature sequentially, and then by controlling a temperature decrease at a rate of 40-80° C./h to a first cooling temperature, a second cooling temperature, and finally to the room temperature sequentially, then obtaining a final product of black phosphorus, wherein the third reaction temperature is greater than the second reaction temperature; and the second reaction temperature is greater than the first reaction temperature; and the first reaction temperature is greater than the room temperature, wherein after reaching the first reaction temperature, the first reaction temperature is maintained for a first time period, after reaching the second reaction temperature, the second reaction temperature is maintained for a second time period, and after reaching the third reaction temperature, the third reaction temperature is maintained for a third time period, wherein after reaching the first cooling temperature, the first cooling temperature is maintained for a first cooling time period, after reaching the second cooling temperature, the second cooling temperature is maintained for a second cooling time period, wherein a total time of the first time period, the second time period and the third time period is approximately 3-8 hours and the third reaction temperature is 520° C.-760° C., wherein a weight ratio of tin: red phosphorus: iodine is 0.8-1.5: 15-25: 0.12-0.25, the reaction raw materials further comprise molybdenum or tungsten having a weight of 0.5-1% of a total weight of the reaction raw materials, the third reaction temperature is 580-660° C., and a volume of the high-temperature resistant metal reaction tube is about 1.5-5 times of a volume of the glass tube.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic diagram illustrating the apparatus and method for producing black phosphorus according to a preferred embodiment of the present invention.

(2) FIG. 2 is a schematic diagram illustrating the method for producing black phosphorus according to the preferred embodiment of the present invention.

(3) FIG. 3 is a photo illustrating the black phosphorus produced by the method of the present invention.

(4) FIG. 4 is a photo illustrating the black phosphorus produced by the method of the present invention.

(5) FIG. 5 is a photo illustrating the black phosphorus produced by the method of the present invention.

(6) FIG. 6 is a photo illustrating the black phosphorus produced by the method of the present invention.

(7) FIG. 7 is a photo illustrating the black phosphorus produced by the method of the present invention.

(8) FIG. 8 is a photo illustrating the black phosphorus produced by the method of the present invention.

(9) FIG. 9 is a photo illustrating the black phosphorus produced by the method of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

(10) Referring to FIG. 1 and FIG. 2 of the drawings, a method of producing black phosphorus comprises the steps of:

(11) (a) weighing reaction raw materials which comprises metallic tin, red phosphorus and monocrystalline iodine, wherein a weight ratio of tin: red phosphorus: iodine is 0.6-3.5: 5-45: 0.1-0.8; and weighing molybdenum or tungsten having a weight of 0.5˜1% of a total weight of the reaction raw materials;

(12) (b) mixing the reaction raw materials and molybdenum/tungsten uniformly to form a mixture;

(13) (c) feeding the mixture to a high-temperature resistant metal reaction tube 20, or alternately, (c′) feeding the mixture to a glass tube 40, replacing air inside the glass tube 40 by inert gas, closing a glass tube opening 44 of the glass tube 40 by a plug 42 and then placing the glass tube 40 inside a high-temperature resistant metal reaction tube 20;

(14) (d) introducing inert gas to the high-temperature resistant metal reaction tube 20 to replace air inside the high-temperature resistant metal reaction tube 20 with the insert gas;

(15) (e) closing and sealing the metal reaction tube 20 tightly by placing a high-temperature resistant metal gasket 24 on a flange member 22 of the metal reaction tube 20, covering the metal reaction tube 20 with the flange member 22 and tightening into position by a screw member 26;

(16) (f) placing the metal reaction tube 20 inside a muffle furnace 60 for carrying out calcination reaction by controlling a temperature increase at a rate 50-80° C./h to a first reaction temperature and keeping warm, to a second reaction temperature and keeping warm and to a third reaction temperature and keeping warm, and then by controlling a temperature decrease at a rate of 40-80° C./h to a first cooling temperature and keeping warm, then to a second cooling temperature and keeping warm, and finally to room temperature, then obtaining a final product of black phosphorus.

(17) Preferably, the step (f) is: placing the metal reaction tube 20 inside a muffle furnace 60 for carrying out calcination reaction by controlling a temperature increase at a rate 50-80° C./h to (i) a first reaction temperature of 500° C. and keeping warm for 10-30 minutes, (ii) a second reaction temperature of 550-580° C. and keeping warm for 30-60 minutes, and (iii) a third reaction temperature of 580-660° C. and keeping warm, and then by controlling a temperature decrease at a rate of 40-80° C./h to (i′) a first cooling temperature of 500° C. and keeping warm for 10-60 minutes, then (ii′) a second cooling temperature of 350° C. and keeping warm for 10-60 minutes, and finally (iii′) room temperature, then obtaining a final product of black phosphorus.

(18) Preferably, a weight ratio of tin: red phosphorus: iodine is 0.8-1.5: 15-25: 0.12-0.25. The third reaction temperature is 580-660° C. The high-temperature resistant metal reaction tube 20 is made of stainless steel, or iron, aluminum, copper, zinc, nickel, tin, antimony and/or lead and their metallic compound. The inert gas used in the glass tube 40 or the metal reaction tube 20 is argon or helium. The size of the high-temperature resistant metal reaction tube 20 is about 1.5˜5 times of a size of the glass tube 40 so that the glass tube 40 can be put in and out of the metal reaction tube 20 easily.

(19) It is worth mentioning that there is no particular pressure requirement for the calcination reaction. In general, the glass tube 40 is closed by the plug 42 during the reaction and the reaction occurs inside the glass tube 40. However, when the pressure is too high, the plug 42 of the glass tube 40 is capable of being unplugged from the glass tube opening 44 to release the pressure while all the reaction raw materials may spill inside the metal reaction tube 20.

Embodiment 1

(20) According to this preferred embodiment of the present invention, a method of producing black phosphorus comprises the steps of:

(21) (a) weighing reaction raw materials, wherein the reaction raw materials has a purity of 99.63% and comprises metallic tin in granular form having a particle size of 1.8 mm, red phosphorus in flake form and monocrystalline iodine in granular form having a particle size of 1.8 mm; and a weight ratio of tin: red phosphorus: iodine=1.4:16:0.24;

(22) (b) mixing the reaction raw materials uniformly to form a mixture;

(23) (c) feeding the mixture to a glass tube 40, replacing air inside the glass tube 40 by helium gas and close a glass tube opening 44 of the glass tube 40 by a plug 42 and then placing the glass tube 40 inside a high-temperature resistant metal reaction tube 20, wherein the high-temperature resistant metal reaction tube 20 is a rectangular tube made of stainless steel having a length of 165 cm, a width of 85 cm, a height of 85 cm and a volume of 4.5 times of a volume of the glass tube 40;

(24) (d) introducing helium gas to the high-temperature resistant metal reaction tube 20 to replace air inside the high-temperature resistant metal reaction tube 20 with the helium gas;

(25) (e) placing a high-temperature resistant metal gasket 24 on a flange member 22 of the metal reaction tube 20, covering the metal reaction tube 20 with the flange member 22 and tightening into position by a screw member 26;

(26) (f) placing the metal reaction tube 20 inside a muffle furnace 60 for carrying out calcination reaction by controlling a temperature increase at a rate 70° C./h to increase a reaction temperature to 500° C. and keeping warm for 15 minutes, then 580° C. and keeping warm for 35 minutes and 590° C. and keeping warm for 7.5 hours, and then by controlling a temperature decrease at a rate of 65° C./h to decrease a cooling temperature to 500° C. and keeping warm for 20 minutes, 350° C. and keeping warm for 45 minutes and to room temperature, and then obtaining a final product of black phosphorus.

(27) The final product of black phosphorus is in the flakes form and a conversion rate is 96.5%.

Embodiment 2

(28) According to this preferred embodiment of the present invention, a method of producing black phosphorus comprises the steps of:

(29) (a) weighing reaction raw materials, wherein the reaction raw materials have a purity of 99.51% and comprises metallic tin in granular form having a particle size of 1.3 mm, red phosphorus in flake form and monocrystalline iodine in granular form having a particle size of 1.5 mm; and a weight ratio of tin: red phosphorus: iodine=1.1:18:0.21;

(30) (b) mixing the reaction raw materials uniformly to form a mixture;

(31) (c) feeding the mixture to a high-temperature resistant metal reaction tube 20, wherein the high-temperature resistant metal reaction tube 20 is a rectangular tube made of Sb.sub.2O.sub.4 having a length of 85 cm, a width of 35 cm and a height of 35 cm;

(32) (d) introducing helium gas to the high-temperature resistant metal reaction tube 20 to replace air inside the high-temperature resistant metal reaction tube 20 with the helium gas;

(33) (e) placing a high-temperature resistant metal gasket 24 on a flange member 22 of the metal reaction tube 20, covering the metal reaction tube 20 with the flange member 22 and tightening into position by a screw member 26;

(34) (f) placing the metal reaction tube 20 inside a muffle furnace 60 for carrying out calcination reaction by controlling a temperature increase at a rate 68° C./h to increase a reaction temperature to 500° C. and keeping warm for 25 minutes, then 580° C. and keeping warm for 50 minutes and 630° C. and keeping warm for 5.5 hours, and then by controlling a temperature decrease at a rate of 65° C./h to decrease a cooling temperature to 500° C. and keeping warm for 18 minutes, 350° C. and keeping warm for 25 minutes and to room temperature, and then obtaining a final product of black phosphorus.

(35) The final product of black phosphorus is in the flakes form and a conversion rate is 97.2%.

Embodiment 3

(36) According to this preferred embodiment of the present invention, a method of producing black phosphorus comprises the steps of:

(37) (a) weighing reaction raw materials, wherein the reaction raw materials has a purity of 99.98% and comprises metallic tin in powder form, red phosphorus in flake form and monocrystalline iodine in granular form having a particle size of 1.5 mm; and a weight ratio of tin: red phosphorus: iodine=1.5:25:0.25;

(38) (b) mixing the reaction raw materials uniformly to form a mixture;

(39) (c) feeding the mixture a high-temperature resistant metal reaction tube 20, wherein the high-temperature resistant metal reaction tube 20 is a cylindrical tube made of stainless steel;

(40) (d) introducing helium gas to the high-temperature resistant metal reaction tube 20 to replace air inside the high-temperature resistant metal reaction tube 20 with the helium gas;

(41) (e) placing a high-temperature resistant metal gasket 24 on a flange member 22 of the metal reaction tube 20, covering the metal reaction tube 20 with the flange member 22 and tightening into position by a screw member 26;

(42) (f) placing the metal reaction tube 20 inside a muffle furnace 60 for carrying out calcination reaction by controlling a temperature increase at a rate 80° C./h to increase a reaction temperature to 500° C. and keeping warm for 10 minutes, then 580° C. and keeping warm for 30 minutes and 660° C. and keeping warm for 6.5 hours, and then by controlling a temperature decrease at a rate of 80° C./h to decrease a cooling temperature to 500° C. and keeping warm for 10 minutes, 350° C. and keeping warm for 10 minutes and to room temperature, and then obtaining a final product of black phosphorus.

(43) The final product of black phosphorus is in the flakes form and a conversion rate is 97.5%.

Embodiment 4

(44) According to this preferred embodiment of the present invention, a method of producing black phosphorus comprises the steps of:

(45) (a) weighing reaction raw materials, wherein the reaction raw materials have a purity of 99.99% and comprises metallic tin in powder form, red phosphorus in flake form and monocrystalline iodine in granular form having a particle size of 1.4 mm; and a weight ratio of tin: red phosphorus: iodine=1.0:20:0.18;

(46) (b) adding molybdenum to the reaction raw materials and mixing uniformly to form a mixture, wherein an amount of molybdenum being added is 0.8% of the total weight of the reaction raw materials;

(47) (c) feeding the mixture to a glass tube 40, replacing air inside the glass tube 40 by argon gas and close a glass tube opening 44 of the glass tube 40 by a plug 42 and then placing the glass tube 40 inside a high-temperature resistant metal reaction tube 20, wherein the high-temperature resistant metal reaction tube 20 is a cylindrical tube made of stainless steel having a diameter of 50 cm, a length of 165 cm, and a volume of 3.0 times of a volume of the glass tube 40;

(48) (d) introducing argon gas to the high-temperature resistant metal reaction tube 20 to replace air inside the high-temperature resistant metal reaction tube 20 with the argon gas;

(49) (e) placing a high-temperature resistant metal gasket 24 on a flange member 22 of the metal reaction tube 20, covering the metal reaction tube 20 with the flange member 22 and tightening into position by a screw member 26;

(50) (f) placing the metal reaction tube 20 inside a muffle furnace 60 for carrying out calcination reaction by controlling a temperature increase at a rate 65° C./h to increase a reaction temperature to 500° C. and keeping warm for 20 minutes, then 580° C. and keeping warm for 45 minutes and 620° C. and keeping warm for 5 hours, and then by controlling a temperature decrease at a rate of 60° C./h to decrease a cooling temperature to 500° C. and keeping warm for 35 minutes, 350° C. and keeping warm for 35 minutes and to room temperature, and then obtaining a final product of black phosphorus.

(51) The final product of black phosphorus is in the flakes form and a conversion rate is 99.1%.

Embodiment 5

(52) According to this preferred embodiment of the present invention, a method of producing black phosphorus comprises the steps of:

(53) (a) weighing reaction raw materials, wherein the reaction raw materials has a purity of 99.98% and comprises metallic tin in granular form having a particle size of 1.4 mm, red phosphorus in flake form and monocrystalline iodine in granular form having a particle size of 1.6 mm; and a weight ratio of tin: red phosphorus: iodine=1.2:20:0.17;

(54) (b) adding tungsten to the reaction raw materials and mixing uniformly to form a mixture, wherein an amount of molybdenum being added is 0.7% of the total weight of the reaction raw materials;

(55) (c) feeding the mixture to a glass tube 40, replacing air inside the glass tube 40 by argon gas and close a glass tube opening 44 of the glass tube 40 by a plug 42 and then placing the glass tube 40 inside a high-temperature resistant metal reaction tube 20, wherein the high-temperature resistant metal reaction tube 20 is a rectangular tube made of stainless steel having a length of 95 cm, a width of 50 cm, a height of 50 cm and a volume of 3.0 times of a volume of the glass tube 40;

(56) (d) introducing argon gas to the high-temperature resistant metal reaction tube 20 to replace air inside the high-temperature resistant metal reaction tube 20 with the argon gas;

(57) (e) placing a high-temperature resistant metal gasket 24 on a flange member 22 of the metal reaction tube 20, covering the metal reaction tube 20 with the flange member 22 and tightening into position by a screw member 26;

(58) (f) placing the metal reaction tube 20 inside a muffle furnace 60 for carrying out calcination reaction by controlling a temperature increase at a rate 65° C./h to increase a reaction temperature to 500° C. and keeping warm for 20 minutes, then 580° C. and keeping warm for 45 minutes and 620° C. and keeping warm for 5 hours, and then by controlling a temperature decrease at a rate of 60° C./h to decrease a cooling temperature to 500° C. and keeping warm for 35 minutes, to 350° C. and keeping warm for 35 minutes and to room temperature, and then obtaining a final product of black phosphorus.

(59) The final product of black phosphorus is in the flakes form and a conversion rate is 98.0%.

Embodiment 6

(60) According to this preferred embodiment of the present invention, a method of producing black phosphorus comprises the steps of:

(61) (a) weighing reaction raw materials, wherein the reaction raw materials have a purity of 99.98% and comprises metallic tin in powder form, red phosphorus in flake form and monocrystalline iodine in granular form having a particle size of 1.5 mm; and a weight ratio of tin: red phosphorus: iodine=1.5:25:0.25;

(62) (b) adding molybdenum to the reaction raw materials and mixing uniformly to form a mixture, wherein an amount of molybdenum being added is 1% of the total weight of the reaction raw materials;

(63) (c) feeding the mixture to a glass tube 40, replacing air inside the glass tube 40 by argon gas and close a glass tube opening 44 of the glass tube 40 by a plug 42 and then placing the glass tube 40 inside a high-temperature resistant metal reaction tube 20, wherein the high-temperature resistant metal reaction tube 20 is a cylindrical tube made of Fe.sub.3O.sub.4 having a diameter of 100 cm, a length of 200 cm, and a volume of 5 times of a volume of the glass tube 40;

(64) (d) introducing argon gas to the high-temperature resistant metal reaction tube 20 to replace air inside the high-temperature resistant metal reaction tube 20 with the argon gas;

(65) (e) placing a high-temperature resistant metal gasket 24 on a flange member 22 of the metal reaction tube 20, covering the metal reaction tube 20 with the flange member 22 and tightening into position by a screw member 26;

(66) (f) placing the metal reaction tube 20 inside a muffle furnace 60 for carrying out calcination reaction by controlling a temperature increase at a rate 80° C./h to increase a reaction temperature to 500° C. and keeping warm for 10 minutes, then 580° C. and keeping warm for 30 minutes and 660° C. and keeping warm for 3 hours, and then by controlling a temperature decrease at a rate of 80° C./h to decrease a cooling temperature to 500° C. and keeping warm for 10 minutes, to 350° C. and keeping warm for 10 minutes and to room temperature, and then obtaining a final product of black phosphorus.

(67) The final product of black phosphorus is in the flakes form and a conversion rate is 97.8%.

Embodiment 7

(68) According to this preferred embodiment of the present invention, a method of producing black phosphorus comprises the steps of:

(69) (a) weighing reaction raw materials, wherein the reaction raw materials have a purity of 99.98% and comprises metallic tin in powder form, red phosphorus in flake form and monocrystalline iodine in granular form having a particle size of 1.7 mm; and a weight ratio of tin: red phosphorus: iodine=0.8:15:0.12;

(70) (b) adding molybdenum to the reaction raw materials and mixing uniformly to form a mixture, wherein an amount of molybdenum being added is 0.5% of the total weight of the reaction raw materials;

(71) (c) feeding the mixture to a high-temperature resistant metal reaction tube 20, wherein the high-temperature resistant metal reaction tube 20 is a cylindrical tube made of Al.sub.2O.sub.3 having a diameter of 2.5 cm and a length of 10 cm;

(72) (d) introducing argon gas to the high-temperature resistant metal reaction tube 20 to replace air inside the high-temperature resistant metal reaction tube 20 with the argon gas;

(73) (e) placing a high-temperature resistant metal gasket 24 on a flange member 22 of the metal reaction tube 20, covering the metal reaction tube 20 with the flange member 22 and tightening into position by a screw member 26;

(74) (f) placing the metal reaction tube 20 inside a muffle furnace 60 for carrying out calcination reaction by controlling a temperature increase at a rate 50° C./h to increase a reaction temperature to 500° C. and keeping warm for 30 minutes, then 550° C. and keeping warm for 60 minutes and 580° C. and keeping warm for 4 hours, and then by controlling a temperature decrease at a rate of 40° C./h to decrease a cooling temperature to 500° C. and keeping warm for 60 minutes, to 350° C. and keeping warm for 60 minutes and to room temperature, and then obtaining a final product of black phosphorus.

(75) The final product of black phosphorus is in the flakes form and a conversion rate is 97.5%.

Embodiment 8

(76) According to this preferred embodiment of the present invention, a method of producing black phosphorus comprises the steps of:

(77) (a) weighing reaction raw materials, wherein the reaction raw materials have a purity of 99.96% and comprises metallic tin in granular form having a particle size of 1.2 mm, red phosphorus in flake form and monocrystalline iodine in granular form having a particle size of 1.2 mm; and a weight ratio of tin: red phosphorus: iodine=1.3:17:0.23;

(78) (b) adding tungsten to the reaction raw materials and mixing uniformly to form a mixture, wherein an amount of tungsten being added is 0.6% of the total weight of the reaction raw materials;

(79) (c) feeding the mixture to a high-temperature resistant metal reaction tube 20, wherein the high-temperature resistant metal reaction tube 20 is a rectangular tube made of CuO having a length of 45 cm, a width of 20 cm and a height of 20 cm;

(80) (d) introducing argon gas to the high-temperature resistant metal reaction tube 20 to replace air inside the high-temperature resistant metal reaction tube 20 with the argon gas;

(81) (e) placing a high-temperature resistant metal gasket 24 on a flange member 22 of the metal reaction tube 20, covering the metal reaction tube 20 with the flange member 22 and tightening into position by a screw member 26;

(82) (f) placing the metal reaction tube 20 inside a muffle furnace 60 for carrying out calcination reaction by controlling a temperature increase at a rate 75° C./h to increase a reaction temperature to 500° C. and keeping warm for 25 minutes, then 580° C. and keeping warm for 45 minutes and 600° C. and keeping warm for 4.5 hours, and then by controlling a temperature decrease at a rate of 55° C./h to decrease a cooling temperature to 500° C. and keeping warm for 25 minutes, to 350° C. and keeping warm for 55 minutes and to room temperature, and then obtaining a final product of black phosphorus.

(83) The final product of black phosphorus is in the flakes form and a conversion rate is 97.9%.

Embodiment 9

(84) According to this preferred embodiment of the present invention, a method of producing black phosphorus comprises the steps of:

(85) (a) weighing reaction raw materials, wherein the reaction raw materials have a purity of 99.95% and comprises metallic tin in powder form, red phosphorus in flake form and monocrystalline iodine in granular form having a particle size of 1.5 mm; and a weight ratio of tin: red phosphorus: iodine=1.2:19:0.19;

(86) (b) adding molybdenum to the reaction raw materials and mixing uniformly to form a mixture, wherein an amount of molybdenum being added is 0.8% of the total weight of the reaction raw materials;

(87) (c) feeding the mixture to a glass tube 40, replacing air inside the glass tube 40 by argon gas and close a glass tube opening 44 of the glass tube 40 by a plug 42 and then placing the glass tube 40 inside a high-temperature resistant metal reaction tube 20, wherein the high-temperature resistant metal reaction tube 20 is a cylindrical tube made of SnO.sub.2 having a diameter of 85 cm, a length of 165 cm, and a volume of 3.3 times of a volume of the glass tube 40;

(88) (d) introducing argon gas to the high-temperature resistant metal reaction tube 20 to replace air inside the high-temperature resistant metal reaction tube 20 with the argon gas;

(89) (e) placing a high-temperature resistant metal gasket 24 on a flange member 22 of the metal reaction tube 20, covering the metal reaction tube 20 with the flange member 22 and tightening into position by a screw member 26;

(90) (f) placing the metal reaction tube 20 inside a muffle furnace 60 for carrying out calcination reaction by controlling a temperature increase at a rate 55° C./h to increase a reaction temperature to 500° C. and keeping warm for 22 minutes, then 580° C. and keeping warm for 50 minutes and 640° C. and keeping warm for 4.5 hours, and then by controlling a temperature decrease at a rate of 66° C./h to decrease a cooling temperature to 500° C. and keeping warm for 32 minutes, to 350° C. and keeping warm for 42 minutes and to room temperature, and then obtaining a final product of black phosphorus.

(91) The final product of black phosphorus is in the flakes form and a conversion rate is 98.4%.

Embodiment 10

(92) According to this preferred embodiment of the present invention, a method of producing black phosphorus comprises the steps of:

(93) (a) weighing reaction raw materials, wherein the reaction raw materials have a purity of 99.93% and comprises metallic tin in granular form having a particle size of 1.3 mm, red phosphorus in flake form and monocrystalline iodine in granular form having a particle size of 1.2 mm; and a weight ratio of tin: red phosphorus: iodine=0.6:5:0.1;

(94) (b) adding tungsten to the reaction raw materials and mixing uniformly to form a mixture, wherein an amount of tungsten being added is 0.8% of the total weight of the reaction raw materials;

(95) (c) feeding the mixture to a high-temperature resistant metal reaction tube 20, wherein the high-temperature resistant metal reaction tube 20 is a rectangular tube made of stainless steel having a length of 125 cm, a width of 75 cm and a height of 75 cm;

(96) (d) introducing argon gas to the high-temperature resistant metal reaction tube 20 to replace air inside the high-temperature resistant metal reaction tube 20 with the argon gas;

(97) (e) placing a high-temperature resistant metal gasket 24 on a flange member 22 of the metal reaction tube 20, covering the metal reaction tube 20 with the flange member 22 and tightening into position by a screw member 26;

(98) (f) placing the metal reaction tube 20 inside a muffle furnace 60 for carrying out calcination reaction by controlling a temperature increase at a rate 60° C./h to increase a reaction temperature to 500° C. and keeping warm for 25 minutes, then 580° C. and keeping warm for 55 minutes and 730° C. and keeping warm for 4 hours, and then by controlling a temperature decrease at a rate of 50° C./h to decrease a cooling temperature to 500° C. and keeping warm for 25 minutes, to 350° C. and keeping warm for 30 minutes and to room temperature, and then obtaining a final product of black phosphorus.

(99) The final product of black phosphorus is in the flakes form and a conversion rate is 98.5%.

Embodiment 11

(100) According to this preferred embodiment of the present invention, a method of producing black phosphorus comprises the steps of:

(101) (a) weighing reaction raw materials, wherein the reaction raw materials has a purity of 99.84% and comprises red phosphorus in flake form, metallic tin in powder form and monocrystalline iodine in granular form having a particle size of 1.7 mm; and a weight ratio of tin: red phosphorus: iodine=3.5:45:0.8;

(102) (b) adding molybdenum to the reaction raw materials and mixing uniformly to form a mixture, wherein an amount of molybdenum being added is 0.9% of the total weight of the reaction raw materials;

(103) (c) feeding the mixture to a glass tube 40, replacing air inside the glass tube 40 by inert gas and close a glass tube opening 44 of the glass tube 40 by a plug 42 and then placing the glass tube 40 inside a high-temperature resistant metal reaction tube 20, wherein the high-temperature resistant metal reaction tube 20 is a cylindrical tube made of lead (Pb) having a diameter of 85 cm, a length of 165 cm and a volume of 3.3 times of a volume of the glass tube 40;

(104) (d) introducing inert gas to the high-temperature resistant metal reaction tube 20 to replace air inside the high-temperature resistant metal reaction tube 20 with the inert gas;

(105) (e) placing a high-temperature resistant metal gasket 24 on a flange member 22 of the metal reaction tube 20, covering the metal reaction tube 20 with the flange member 22 and tightening into position by a screw member 26;

(106) (f) placing the metal reaction tube 20 inside a muffle furnace 60 for carrying out calcination reaction by controlling a temperature increase at a rate 65° C./h to increase a reaction temperature to 500° C. and keeping warm for 26 minutes, then 580° C. and keeping warm for 36 minutes and 615° C. and keeping warm for 5 hours, and then by controlling a temperature decrease at a rate of 73° C./h to decrease a cooling temperature to 500° C. and keeping warm for 50 minutes, 350° C. and keeping warm for 30 minutes and to room temperature, and then obtaining a final product of black phosphorus.

(107) The final product of black phosphorus is in the flakes form and a conversion rate is 97.2%.

Embodiment 12

(108) According to this preferred embodiment of the present invention, a method of producing black phosphorus comprises the steps of:

(109) (a) weighing reaction raw materials, wherein the reaction raw materials have a purity of 99.77% and comprises red phosphorus in flake form, metallic tin in powder form and monocrystalline iodine in granular form having a particle size of 1.7 mm; and a weight ratio of tin: red phosphorus: iodine=1.4:16:0.23;

(110) (b) mixing uniformly to form a mixture;

(111) (c) feeding the mixture to a glass tube 40, replacing air inside the glass tube 40 by argon gas and close a glass tube opening 44 of the glass tube 40 by a plug 42 and then placing the glass tube 40 inside a high-temperature resistant metal reaction tube 20, wherein the high-temperature resistant metal reaction tube 20 is a cylindrical tube made of zinc (Zn) having a diameter of 25 cm, a length of 45 cm and a volume of 2.4 times of a volume of the glass tube 40;

(112) (d) introducing argon gas to the high-temperature resistant metal reaction tube 20 to replace air inside the high-temperature resistant metal reaction tube 20 with the argon gas;

(113) (e) placing a high-temperature resistant metal gasket 24 on a flange member 22 of the metal reaction tube 20, covering the metal reaction tube 20 with the flange member 22 and tightening into position by a screw member 26;

(114) (f) placing the metal reaction tube 20 inside a muffle furnace 60 for carrying out calcination reaction by controlling a temperature increase at a rate 63° C./h to increase a reaction temperature to 500° C. and keeping warm for 22 minutes, then 580° C. and keeping warm for 48 minutes and 650° C. and keeping warm for 3.5 hours, and then by controlling a temperature decrease at a rate of 54° C./h to decrease a cooling temperature to 500° C. and keeping warm for 54 minutes, 350° C. and keeping warm for 24 minutes and to room temperature, and then obtaining a final product of black phosphorus.

(115) The final product of black phosphorus is in the flakes form and a conversion rate is 97.6%.

(116) The final product of black phosphorus produced by embodiment 1-12 has a large surface area and a flaky structure with a metallic luster at the same time, thus classifying as high quality black phosphorus.

(117) The black phosphorus, which is of very high quality, produced by embodiments 1-12 are illustrated by FIGS. 3-9 of the drawings.

(118) One skilled in the art will understand that the embodiment of the present invention as shown in the drawings and described above is exemplary only and not intended to be limiting.

(119) It will thus be seen that the objects of the present invention have been fully and effectively accomplished. It embodiments have been shown and described for the purposes of illustrating the functional and structural principles of the present invention and is subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.