CN1569368A - Method for preparing nm-class composite rare earth molybdenum material by sol-gal process - Google Patents
Method for preparing nm-class composite rare earth molybdenum material by sol-gal process Download PDFInfo
- Publication number
- CN1569368A CN1569368A CN 200410026104 CN200410026104A CN1569368A CN 1569368 A CN1569368 A CN 1569368A CN 200410026104 CN200410026104 CN 200410026104 CN 200410026104 A CN200410026104 A CN 200410026104A CN 1569368 A CN1569368 A CN 1569368A
- Authority
- CN
- China
- Prior art keywords
- rare earth
- molybdenum
- aqueous solution
- ammonium molybdate
- temperature
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000000463 material Substances 0.000 title claims abstract description 28
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 title claims abstract description 22
- 239000011733 molybdenum Substances 0.000 title claims abstract description 22
- 229910052761 rare earth metal Inorganic materials 0.000 title claims abstract description 16
- 238000000034 method Methods 0.000 title claims abstract description 15
- 239000002131 composite material Substances 0.000 title claims abstract description 13
- 229910052750 molybdenum Inorganic materials 0.000 title claims abstract description 13
- 150000002910 rare earth metals Chemical class 0.000 title claims abstract description 10
- MRELNEQAGSRDBK-UHFFFAOYSA-N lanthanum(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[La+3].[La+3] MRELNEQAGSRDBK-UHFFFAOYSA-N 0.000 claims abstract description 46
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 claims abstract description 42
- 239000007864 aqueous solution Substances 0.000 claims abstract description 39
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 24
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 24
- 239000001257 hydrogen Substances 0.000 claims abstract description 24
- 239000000843 powder Substances 0.000 claims abstract description 22
- 235000018660 ammonium molybdate Nutrition 0.000 claims abstract description 18
- APUPEJJSWDHEBO-UHFFFAOYSA-P ammonium molybdate Chemical compound [NH4+].[NH4+].[O-][Mo]([O-])(=O)=O APUPEJJSWDHEBO-UHFFFAOYSA-P 0.000 claims abstract description 17
- 229940010552 ammonium molybdate Drugs 0.000 claims abstract description 17
- 239000011609 ammonium molybdate Substances 0.000 claims abstract description 17
- 229910001404 rare earth metal oxide Inorganic materials 0.000 claims abstract description 12
- 239000002114 nanocomposite Substances 0.000 claims abstract description 11
- 238000003980 solgel method Methods 0.000 claims abstract description 7
- JKQOBWVOAYFWKG-UHFFFAOYSA-N molybdenum trioxide Chemical compound O=[Mo](=O)=O JKQOBWVOAYFWKG-UHFFFAOYSA-N 0.000 claims abstract description 6
- -1 rare earth nitrate Chemical class 0.000 claims abstract description 6
- 229910002651 NO3 Inorganic materials 0.000 claims abstract description 5
- 239000011259 mixed solution Substances 0.000 claims abstract description 3
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 26
- 229910017604 nitric acid Inorganic materials 0.000 claims description 26
- QGAVSDVURUSLQK-UHFFFAOYSA-N ammonium heptamolybdate Chemical compound N.N.N.N.N.N.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.O.[Mo].[Mo].[Mo].[Mo].[Mo].[Mo].[Mo] QGAVSDVURUSLQK-UHFFFAOYSA-N 0.000 claims description 22
- XUFUCDNVOXXQQC-UHFFFAOYSA-L azane;hydroxy-(hydroxy(dioxo)molybdenio)oxy-dioxomolybdenum Chemical compound N.N.O[Mo](=O)(=O)O[Mo](O)(=O)=O XUFUCDNVOXXQQC-UHFFFAOYSA-L 0.000 claims description 18
- 238000007731 hot pressing Methods 0.000 claims description 14
- 238000001035 drying Methods 0.000 claims description 12
- 235000005979 Citrus limon Nutrition 0.000 claims 1
- 244000248349 Citrus limon Species 0.000 claims 1
- 239000002253 acid Substances 0.000 claims 1
- 239000010406 cathode material Substances 0.000 abstract description 13
- 239000000203 mixture Substances 0.000 abstract description 11
- 239000003870 refractory metal Substances 0.000 abstract description 2
- 239000013078 crystal Substances 0.000 abstract 1
- YXEUGTSPQFTXTR-UHFFFAOYSA-K lanthanum(3+);trihydroxide Chemical compound [OH-].[OH-].[OH-].[La+3] YXEUGTSPQFTXTR-UHFFFAOYSA-K 0.000 abstract 1
- 239000002105 nanoparticle Substances 0.000 abstract 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract 1
- FYDKNKUEBJQCCN-UHFFFAOYSA-N lanthanum(3+);trinitrate Chemical compound [La+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O FYDKNKUEBJQCCN-UHFFFAOYSA-N 0.000 description 19
- 239000000243 solution Substances 0.000 description 19
- NCUIHVUMEAKBHH-UHFFFAOYSA-N [Mo+4].[O-2].[La+3] Chemical compound [Mo+4].[O-2].[La+3] NCUIHVUMEAKBHH-UHFFFAOYSA-N 0.000 description 11
- 238000003825 pressing Methods 0.000 description 11
- 238000005245 sintering Methods 0.000 description 11
- 238000002679 ablation Methods 0.000 description 10
- 238000001816 cooling Methods 0.000 description 10
- 238000001704 evaporation Methods 0.000 description 10
- 238000002474 experimental method Methods 0.000 description 10
- 238000010438 heat treatment Methods 0.000 description 10
- 230000015556 catabolic process Effects 0.000 description 9
- KTUFCUMIWABKDW-UHFFFAOYSA-N oxo(oxolanthaniooxy)lanthanum Chemical compound O=[La]O[La]=O KTUFCUMIWABKDW-UHFFFAOYSA-N 0.000 description 9
- 238000003756 stirring Methods 0.000 description 9
- 238000005303 weighing Methods 0.000 description 9
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- BABYXVRSXZSKEF-UHFFFAOYSA-N [W+4].[O-2].[Th+4].[O-2].[O-2].[O-2] Chemical compound [W+4].[O-2].[Th+4].[O-2].[O-2].[O-2] BABYXVRSXZSKEF-UHFFFAOYSA-N 0.000 description 4
- 238000002360 preparation method Methods 0.000 description 4
- 238000000498 ball milling Methods 0.000 description 2
- QXYJCZRRLLQGCR-UHFFFAOYSA-N dioxomolybdenum Chemical compound O=[Mo]=O QXYJCZRRLLQGCR-UHFFFAOYSA-N 0.000 description 2
- 238000010304 firing Methods 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- ZSLUVFAKFWKJRC-IGMARMGPSA-N 232Th Chemical compound [232Th] ZSLUVFAKFWKJRC-IGMARMGPSA-N 0.000 description 1
- 229910052776 Thorium Inorganic materials 0.000 description 1
- CBPOHXPWQZEPHI-UHFFFAOYSA-N [Mo].[La] Chemical compound [Mo].[La] CBPOHXPWQZEPHI-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229910000476 molybdenum oxide Inorganic materials 0.000 description 1
- 239000002086 nanomaterial Substances 0.000 description 1
- PQQKPALAQIIWST-UHFFFAOYSA-N oxomolybdenum Chemical compound [Mo]=O PQQKPALAQIIWST-UHFFFAOYSA-N 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
Landscapes
- Inorganic Compounds Of Heavy Metals (AREA)
Abstract
本发明公开了一种难熔金属材料，属于复合纳米材料领域。特别涉及利用溶胶－凝胶法制备纳米复合稀土钼材料的方法。其方法为，在钼酸铵水溶液中，先加入柠檬酸，再将稀土硝酸盐水溶液加入到钼酸铵及柠檬酸混合溶液中。在烘箱中温度为烘干水分，形成干凝胶。然后将干凝胶在马弗炉中灼烧，形成三氧化钼及氧化镧或氢氧化镧混合物。最后在氢气炉中400－450℃及800℃－900℃各还原1.5－2.5小时。将还原后的复合稀土氧化镧钼粉在压力下冷压成形，然后在氢气炉中高温加压条件下，热压烧结成形。该材料晶粒细小，密度可达钼理论密度的95％，稀土氧化物以纳米粒子存在，发射能力强，可作为新型阴极材料。The invention discloses a refractory metal material and belongs to the field of composite nanometer materials. In particular, it relates to a method for preparing nanocomposite rare earth molybdenum materials by using a sol-gel method. The method is as follows: in the ammonium molybdate aqueous solution, citric acid is first added, and then the rare earth nitrate aqueous solution is added to the ammonium molybdate and citric acid mixed solution. The temperature in the oven is to dry the water and form a xerogel. The xerogel is then fired in a muffle furnace to form a mixture of molybdenum trioxide and lanthanum oxide or lanthanum hydroxide. Finally, reduce in a hydrogen furnace for 1.5-2.5 hours at 400-450°C and 800-900°C respectively. The reduced composite rare-earth lanthanum-molybdenum oxide powder is cold-pressed and formed under pressure, and then hot-pressed and sintered in a hydrogen furnace under high-temperature and high-pressure conditions. The crystal grain of the material is fine, and the density can reach 95% of the theoretical density of molybdenum. The rare earth oxide exists in the form of nanoparticles and has strong emission ability, which can be used as a new cathode material.
Description
Technical Field
The invention relates to a refractory metal material, belongs to the field of composite nano materials, and particularly relates to a method for preparing a nano composite rare earth molybdenum material by using sol-gel.
Background
The traditional hot cathode material adopts tungsten-thorium oxide material. The working characteristics are as follows: the working temperature is over 1800 ℃, and the thorium element has radioactivity. The rare earth molybdenum material is prepared by doping a certain amount of rare earth oxide in molybdenum and performing plastic processing, so that the excellent cathode material can be prepared, and has the characteristics of environment friendliness, high toughness and strong emission capability, and the working temperature is below 1500 ℃.
At present, the unit molybdenum lanthanum oxide material is researched at home and abroad. In a japanese patent (JP59-17954) it is mentioned that a lanthanum-molybdenum material is both a structural material and a thermionic emission material. The domestic Beijing industry university starts to comprehensively research the thermionic emission performance of the molybdenum lanthanum oxide material and the related mechanism problem thereof, and makes some progress in the aspects of material preparation, cathode structure and electron emission mechanism research. Their studies were published in the "journal of the university of Industrial Beijing" (volume 27, pp290-293, 2001).
Research on the preparation method of the molybdenum oxide powder is that Nie \31066ofBeijing university of industry, Keren and the like adopt a conventional doping method, namely molybdenum dioxide powder and a lanthanum nitrate solution in a certain proportion are mixed in a solid-liquid manner, stirred, sintered and ground. Reducing to form micron-sized rare earth molybdenum composite powder. The cathode material is prepared by conventional pressing and sintering (see patent CN 1360079A). The presence of nano lanthanum oxide was unexpectedly found in experiments, which were believed to be beneficial for hot cathode emission, but was not further investigated. The problem group of the teaching of the T-bit Jun in the great of the Western-Ann intersection has published the preparation of the nano-composite tungsten-thorium oxide material by the ball milling method on materials letters (pp 2776-2779 in 57 year 2003). The 0-3 type nanometer composite tungsten-thorium oxide is successfully prepared at home and abroad by a vacuum hot pressing method for the first time, the emission performance of the material is obviously improved compared with the conventional emission performance, and the nano rare earth oxide can obviously improve the emission performance of the material. However, iron impurities are inevitably introduced into the tungsten-thorium oxide prepared by the ball milling method, which affects further improvement of the emission performance of the cathode, reduces the processing performance of the material, increases the brittleness of the material, and the use of the material in vacuum is affected by low content of iron impurities.
Disclosure of Invention
The invention aims to provide a method for preparing a nano composite rare earth molybdenum material by using a sol-gel method, which has strong thermionic emission capability, strong ablation resistance capability, fine tissue and good strength plasticity.
The technical scheme of the invention is realized as follows: the method is realized by the following steps:
(1) preparing an ammonium molybdate aqueous solution with the concentration of 17.5-26.1%, adding citric acid with the mass equal to that of ammonium molybdate into the ammonium molybdate aqueous solution, adding lanthanum oxide into nitric acid according to the mass of 1.39-2.97% of ammonium molybdate, wherein the concentration of the nitric acid is 55-70%, and the mass of the nitric acid is 6.95-17.82% of the mass of ammonium molybdate, and preparing a rare earth nitrate aqueous solution; adding the rare earth nitrate aqueous solution into a mixed solution of ammonium molybdate aqueous solution and citric acid, adding nitric acid to adjust the pH to 0.7-3, heating in a stirrer and a water-soluble pot, keeping the constant temperature at 80-90 ℃, evaporating and crystallizing to obtain sol, cooling to room temperature at 23-27 ℃ to obtain gel, drying moisture in a drying oven at the temperature of 100-125 ℃ until the gel turns blue, firing in a muffle furnace at the firing temperature of 400-450 ℃ to obtain molybdenum trioxide and rare earth oxide nano composite powder;
(2) heating and reducing the obtained powder in a hydrogen furnace at the temperature of 400-450 DEG C The reaction is carried out at the temperature of 800-900 DEG C Reacting, and reducing for 1.5-2.5 hours respectively to obtain nano molybdenum-rare earth oxide composite powder;
(3) the reduced composite nano molybdenum-rare earth oxide composite powder is formed by cold pressing under the pressure of 450MPa-550MPa, then is formed by hot pressing in a hydrogen furnace, and is formed by hot pressing sintering under the hot pressing temperature of 1400-1600 ℃ and the pressure of 45MPa-55 MPa.
The ammonium molybdate refers to ammonium dimolybdate or ammonium heptamolybdate.
The utility model discloses utilize the sol-gel method to prepare out the even nanocomposite that the rare earth oxide crystalline grain is littleer that contains, because the existence of nanometer lanthanum oxide is favorable to the hot cathode emission, consequently prepare out the even nanocomposite that the rare earth oxide crystalline grain is littleer with the sol-gel method, the block material is prepared out through the metallurgical method to the nanometer composite powder, and the granularity of rare earth oxide through in the molybdenum substrate of final preparation is less than 90nm, the nanometer composite rare earth molybdenum material of making, the transmitting power is strong.
Detailed Description
The present invention will be described in further detail with reference to the following examples:
the first embodiment is as follows:
88.32 g of ammonium heptamolybdate were weighed out to prepare a 17.5% ammonium heptamolybdate aqueous solution, and 88.32 g of citric acid was weighed out and completely dissolved in the ammonium heptamolybdate aqueous solution. Weighing 1.28 g of lanthanum oxide, completely dissolving the lanthanum oxide in 7ml of nitric acid to prepare a lanthanum nitrate solution, and pouring the prepared lanthanum nitrate solution into an ammonium heptamolybdate aqueous solution; nitric acid was added to adjust the pH to 1.5. Heating to 90 deg.C in water-soluble pot, stirring with electric stirrer, evaporating to obtain sol, and cooling to obtain gel at room temperature. Drying in an oven at 110 ℃. Putting the mixture into a muffle furnace to be burned at 450 ℃. Reducing the burned powder in a hydrogen furnace at 450 ℃ and 850 ℃ in two sections to obtain the molybdenum/lanthanum oxide nano powder. Thencold pressing and forming are carried out under the pressure of 500MPa, and then hot pressing and sintering forming are carried out in a hydrogen furnace at 1500 ℃ and under the pressure of 45 MPa. After the breakdown experiment, the nano molybdenum lanthanum oxide cathode material has many emission points and small ablation degree.
Example two:
85.00 g of ammonium dimolybdate is weighed to prepare an ammonium dimolybdate aqueous solution with the concentration of 18 percent, and 85.00 g of citric acid is weighed and completely dissolved in the ammonium dimolybdate aqueous solution. Weighing 1.36 g of lanthanum oxide, completely dissolving the lanthanum oxide in 8ml of nitric acid to prepare a lanthanum nitrate solution, and then adding the prepared lanthanum nitrate solution into an ammonium dimolybdate aqueous solution; nitric acid was added to adjust the pH to 1.2. Heating to 85 deg.C in water-soluble pot, stirring with electric stirrer, evaporating to obtain sol, and cooling to obtain gel at room temperature. Drying in an oven at 115 ℃. Putting the mixture into a muffle furnace to be burned at the temperature of 420 ℃. And reducing the burned powder in a hydrogen furnace at 420 ℃ and 860 ℃ for two sections to obtain the molybdenum/lanthanum oxide nano powder. Then cold pressing and forming are carried out under 480MPa, and then hot pressing and sintering forming are carried out in a hydrogen furnace at 1450 ℃ and under 50 MPa. After the breakdown experiment, the nano molybdenum lanthanum oxide cathode material has many emission points and small ablation degree.
Example three:
126.96 g of ammonium dimolybdate was weighed out to prepare an ammonium dimolybdate aqueous solution with a concentration of 18.6%, and 126.96 g of citric acid was weighed out and completely dissolved in the ammonium dimolybdate aqueous solution. Weighing 2.3 g of lanthanum oxide, completely dissolving the lanthanum oxide in 13ml of nitric acid to prepare a lanthanum nitrate solution, and then adding the prepared lanthanum nitrate solution into an ammonium dimolybdate aqueous solution; nitric acid was added and the pH was adjusted to 2. Heating to 83 deg.C in water-soluble pot, stirring with electric stirrer, evaporating to obtain sol, and cooling to obtain gel at room temperature. Drying in an oven at 115 ℃. Putting the mixture into a muffle furnace to be burned at 430 ℃. And reducing the burned powder in a hydrogen furnace at 430 ℃ and 870 ℃ in two sections to obtain the molybdenum/lanthanum oxide nano powder. Then cold pressing and forming are carried out under the pressure of 470MPa, and then hot pressing and sintering forming are carried out in a hydrogen furnace at 1550 ℃ and under the pressure of 55 MPa. After the breakdown experiment, the nano molybdenum lanthanum oxide cathode material has many emission points and small ablation degree.
Example four:
176.64 g of ammonium heptamolybdate were weighed out to prepare a 19.2% strength aqueous solution of ammonium heptamolybdate, and 176.64 g of citric acid was weighed out and completely dissolved in the aqueous solution of ammonium heptamolybdate. Weighing 3.5 g of lanthanum oxide, completely dissolving the lanthanum oxide in 20ml of nitric acid to prepare a lanthanum nitrate solution, and then adding the prepared lanthanum nitrate solution into an ammonium heptamolybdate aqueous solution; nitric acid was added and the pH was adjusted to 2.3. Heating to 87 deg.C in water-soluble pot, stirring with electric stirrer, evaporating to obtain sol, and cooling to obtain gel at room temperature. Drying in an oven at 105 ℃. Putting the mixture into a muffle furnace to be burned at the temperature of 410 ℃. And reducing the burned powder in a hydrogen furnace at 435 ℃ and 860 ℃ for two sections to obtain the molybdenum/lanthanum oxide nano powder. Then cold pressing and forming are carried out under the pressure of 520MPa, and then hot pressing and sintering forming are carried out in a hydrogen furnace at the temperature of 1570 ℃ under the pressure of 60 MPa. After the breakdown experiment, the nano molybdenum lanthanum oxide cathode material has many emission points and small ablation degree.
Example five:
106.53 g of ammonium heptamolybdate were weighed out to prepare a 19.7% strength aqueous solution of ammonium heptamolybdate, and 106.53 g of citric acid was weighed out and dissolved completely in the aqueous solution of ammonium heptamolybdate. Weighing 2.4 g of lanthanum oxide, completely dissolving the lanthanum oxide in 14ml of nitric acid to prepare a lanthanum nitrate solution, and then adding the prepared lanthanum nitrate solution into an ammonium heptamolybdate aqueous solution; nitric acid was added and the pH was adjusted to 2.5. Adding into water-soluble pot, adding into 90 deg.C, stirring with electric stirrer, evaporating to obtain sol, and cooling at room temperature to obtain gel. Drying in an oven at 105 ℃. Putting the mixture into a muffle furnace to be burned at 415 ℃. Reducing the burned powder in a hydrogen furnace at 500 ℃ and 800 ℃ in two stages to obtain the molybdenum/lanthanum oxide nano powder. Then cold pressing and forming are carried out under 540MPa pressure, and then hot pressing and sintering forming are carried out in a hydrogen furnace at 1560 ℃ under 48MPa pressure. After the breakdown experiment, the nano molybdenum lanthanum oxide cathode material has many emission points and small ablation degree.
Example six:
84.10 g of ammonium dimolybdate were weighed out to prepare a 22.3% strength aqueous solution of ammonium dimolybdate, and 84.10 g of citric acid was weighed out and dissolved completely in the aqueous solution of ammonium dimolybdate. Weighing 2.0 g of lanthanum oxide, completely dissolving the lanthanum oxide in 12ml of nitric acid to prepare a lanthanum nitrate solution, and then adding the prepared lanthanum nitrate solution into an ammonium dimolybdate aqueous solution; adding nitric acid, adjusting pH to 2.7, heating to 85 deg.C in water-soluble pot, stirring with electric stirrer, evaporating to obtain sol, and cooling to obtain gel at room temperature. Drying in an oven at 115 ℃. Putting the mixture into a muffle furnace, and burning the mixture at 435 ℃. Reducing the burned powder in a hydrogen furnace at 445 ℃ and 840 ℃ for two sections to obtain the molybdenum/lanthanum oxide nano powder. Then cold pressing and forming are carried out under the pressure of 470MPa, and then hot pressing and sintering forming are carried out in a hydrogen furnace at 1520 ℃ under the pressure of 45 MPa. After the breakdown experiment, the nano molybdenum lanthanum oxide cathode material has many emission points and small ablation degree.
Example seven:
178.66 g of ammonium heptamolybdate were weighed out to prepare a 23.5% strength aqueous solution of ammonium heptamolybdate, and 178.66 g of citric acid was weighed out and dissolved completely in the aqueous solution of ammonium heptamolybdate. Weighing 4.6 g of lanthanum oxide, completely dissolving the lanthanum oxide in 28ml of nitric acid to prepare a lanthanum nitrate solution, and then adding the prepared lanthanum nitrate solution into an ammonium heptamolybdate aqueous solution; adding nitric acid, adjusting pH to 3, heating to 90 deg.C in water-soluble pot, stirring with electric stirrer, evaporating to obtain sol, and cooling to obtain gel at room temperature. Drying in an oven at 120 ℃. Putting the mixture into a muffle furnace to be burned at 400 ℃. And reducing the burned powder in a hydrogen furnace at 450 ℃ and 830 ℃ in two stages to obtain the molybdenum/lanthanum oxide nanopowder. Then cold pressing and forming are carried out under the pressure of 500MPa, and then hot pressing and sintering forming are carried out in a hydrogen furnace at 1500 ℃ and under the pressure of 50 MPa. After the breakdown experiment, the nano molybdenum lanthanum oxide cathode material has many emission points and small ablation degree.
Example eight:
171.41 g of ammonium dimolybdate were weighed out to prepare a 25.3% strength aqueous solution of ammonium dimolybdate, and 171.41 g of citric acid was weighed out and dissolved completely in the aqueous solution of ammonium dimolybdate. Weighing 4.8 g of lanthanum oxide, completely dissolving the lanthanum oxide in 30ml of nitric acid to prepare a lanthanum nitrate solution, and then adding the prepared lanthanum nitrate solution into an ammonium dimolybdate aqueous solution; adding nitric acid, adjusting pH to 0.9, heating to 85 deg.C in water-soluble pot, stirring with electric stirrer, evaporating to obtain sol, and cooling to obtain gel at room temperature. Drying in an oven at 115 ℃. Putting the mixture into a muffle furnace to be burned at 405 ℃. Reducing the burned powder in a hydrogen furnace at 450 ℃ and 810 ℃ in two stages to obtain the molybdenum/lanthanum oxide nano powder. Then cold pressing and forming are carried out under the pressure of 550MPa, and then hot pressing and sintering forming are carried out in a hydrogen furnace at 1550 ℃ and under the pressure of 55 MPa. After the breakdown experiment, the nano molybdenum lanthanum oxide cathode material has many emission points and small ablation degree.
Example nine:
175.90 g of ammonium heptamolybdate were weighed out to prepare a 26.1% ammonium heptamolybdate aqueous solution, and 175.90 g of citric acid was weighed out and completely dissolved in the ammonium heptamolybdate aqueous solution. Weighing 5.2 g of lanthanumoxide, completely dissolving the lanthanum oxide in 34ml of nitric acid to prepare a lanthanum nitrate solution, and then adding the prepared lanthanum nitrate solution into an ammonium heptamolybdate aqueous solution; adding nitric acid, adjusting pH to 2.5, heating to 90 deg.C in water-soluble pot, stirring with electric stirrer, evaporating to obtain sol, and cooling at room temperature to obtain gel. Drying in an oven at 125 ℃. Putting the mixture into a muffle furnace to be burned at 440 ℃. Reducing the burned powder in a hydrogen furnace at 480 ℃ and 880 ℃ for two sections to obtain the molybdenum/lanthanum oxide nano powder. Then cold pressing and forming are carried out under the pressure of 530MPa, and then hot pressing and sintering forming are carried out in a hydrogen furnace at the temperature of 1560 ℃ and under the pressure of 45 MPa. After the breakdown experiment, the nano molybdenum lanthanum oxide cathode material has many emission points and small ablation degree.
As the ammonium molybdate, various conventional ammonium molybdates can be used.
Claims (2)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200410026104 CN1244428C (en) | 2004-05-10 | 2004-05-10 | Method for preparing nm-class composite rare earth molybdenum material by sol-gal process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200410026104 CN1244428C (en) | 2004-05-10 | 2004-05-10 | Method for preparing nm-class composite rare earth molybdenum material by sol-gal process |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1569368A true CN1569368A (en) | 2005-01-26 |
| CN1244428C CN1244428C (en) | 2006-03-08 |
Family
ID=34480588
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200410026104 Expired - Fee Related CN1244428C (en) | 2004-05-10 | 2004-05-10 | Method for preparing nm-class composite rare earth molybdenum material by sol-gal process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1244428C (en) |
Cited By (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100409981C (en) * | 2005-10-27 | 2008-08-13 | 江苏大学 | A kind of method that organic gel-thermal reduction method prepares fine metal fiber |
| CN100439522C (en) * | 2006-12-15 | 2008-12-03 | 西部金属材料股份有限公司 | Process for preparing molybdenum-lanthanum alloy |
| CN100462457C (en) * | 2007-05-25 | 2009-02-18 | 株洲硬质合金集团有限公司 | Method for preparing dipping molybdenum alloy |
| CN101353264B (en) * | 2008-09-26 | 2010-04-21 | 北京科技大学 | A method for improving the microstructure of ceramic metallization layer |
| CN102896317A (en) * | 2012-10-23 | 2013-01-30 | 上海大学 | Method for preparing Mo-ZrO2 cermet electrode by sol-gel method |
| WO2013117080A1 (en) * | 2012-02-09 | 2013-08-15 | 华为技术有限公司 | Heterojunction nanomaterial, cathode pole piece for lithium-ion batteries, and lithium-ion battery |
| US8591773B2 (en) | 2012-02-09 | 2013-11-26 | Huawei Technologies Co., Ltd. | Heterojunction nano material, negative pole piece of lithium ion battery, and lithium ion battery |
| CN104294133A (en) * | 2014-01-21 | 2015-01-21 | 河南科技大学 | A kind of ZrO2 ceramic particle reinforced molybdenum-based composite material and preparation method thereof |
| CN104328301A (en) * | 2014-07-18 | 2015-02-04 | 河南科技大学 | Preparation method of particular-reinforced molybdenum-based composite material |
| CN104470658A (en) * | 2012-05-29 | 2015-03-25 | H·C·施塔克公司 | Metal crucible and method of forming same |
| CN106363166A (en) * | 2016-09-12 | 2017-02-01 | 厦门理工学院 | A kind of nano-La2O3 uniformly doped nano-molybdenum composite powder and its preparation method |
| CN108149042A (en) * | 2017-12-22 | 2018-06-12 | 北京工业大学 | A kind of cryogenic activating sintering preparation method of high-compactness molybdenum material |
| CN108439469A (en) * | 2018-02-13 | 2018-08-24 | 浙江大学 | A kind of preparation of silver molybdate nano-powder in subsphaeroidal structure and application process |
| CN111187958A (en) * | 2020-02-19 | 2020-05-22 | 西安交通大学 | Method for preparing nano-lanthanum oxide molybdenum alloy by doping Mo powder/MoO2 and lanthanum molybdate powder |
| CN112176236A (en) * | 2020-10-19 | 2021-01-05 | 北京工业大学 | La2O3W-Mo-doped alloy material and preparation method thereof |
| CN113549456A (en) * | 2021-08-18 | 2021-10-26 | 北京工业大学 | A kind of preparation method of multiphase lanthanum molybdate mixed luminescent material without rare earth doping that can emit light at room temperature |
| CN113798504A (en) * | 2021-09-17 | 2021-12-17 | 郑州大学 | Preparation method of rare earth oxide dispersion reinforced tungsten powder for 3D printing |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101698919B (en) * | 2009-11-04 | 2012-07-18 | 河南科技大学 | Particle-reinforced molybdenum-base composite material and preparation method thereof |
-
2004
- 2004-05-10 CN CN 200410026104 patent/CN1244428C/en not_active Expired - Fee Related
Cited By (25)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100409981C (en) * | 2005-10-27 | 2008-08-13 | 江苏大学 | A kind of method that organic gel-thermal reduction method prepares fine metal fiber |
| CN100439522C (en) * | 2006-12-15 | 2008-12-03 | 西部金属材料股份有限公司 | Process for preparing molybdenum-lanthanum alloy |
| CN100462457C (en) * | 2007-05-25 | 2009-02-18 | 株洲硬质合金集团有限公司 | Method for preparing dipping molybdenum alloy |
| CN101353264B (en) * | 2008-09-26 | 2010-04-21 | 北京科技大学 | A method for improving the microstructure of ceramic metallization layer |
| WO2013117080A1 (en) * | 2012-02-09 | 2013-08-15 | 华为技术有限公司 | Heterojunction nanomaterial, cathode pole piece for lithium-ion batteries, and lithium-ion battery |
| US8591773B2 (en) | 2012-02-09 | 2013-11-26 | Huawei Technologies Co., Ltd. | Heterojunction nano material, negative pole piece of lithium ion battery, and lithium ion battery |
| CN104470658A (en) * | 2012-05-29 | 2015-03-25 | H·C·施塔克公司 | Metal crucible and method of forming same |
| CN102896317A (en) * | 2012-10-23 | 2013-01-30 | 上海大学 | Method for preparing Mo-ZrO2 cermet electrode by sol-gel method |
| CN104294133A (en) * | 2014-01-21 | 2015-01-21 | 河南科技大学 | A kind of ZrO2 ceramic particle reinforced molybdenum-based composite material and preparation method thereof |
| CN104294133B (en) * | 2014-01-21 | 2016-08-17 | 河南科技大学 | A kind of ZrO2 ceramic particle reinforced molybdenum-based composite material and preparation method thereof |
| CN104328301A (en) * | 2014-07-18 | 2015-02-04 | 河南科技大学 | Preparation method of particular-reinforced molybdenum-based composite material |
| CN104328301B (en) * | 2014-07-18 | 2016-08-31 | 河南科技大学 | A kind of preparation method of particle-reinforced molybdenum-base composite material |
| CN106363166A (en) * | 2016-09-12 | 2017-02-01 | 厦门理工学院 | A kind of nano-La2O3 uniformly doped nano-molybdenum composite powder and its preparation method |
| CN106363166B (en) * | 2016-09-12 | 2019-03-01 | 厦门理工学院 | A kind of nanometer of La2O3Uniform Doped nanometer molybdenum composite powder and preparation method thereof |
| CN108149042A (en) * | 2017-12-22 | 2018-06-12 | 北京工业大学 | A kind of cryogenic activating sintering preparation method of high-compactness molybdenum material |
| CN108149042B (en) * | 2017-12-22 | 2020-04-14 | 北京工业大学 | A low-temperature activation sintering preparation method of high-density molybdenum material |
| CN108439469A (en) * | 2018-02-13 | 2018-08-24 | 浙江大学 | A kind of preparation of silver molybdate nano-powder in subsphaeroidal structure and application process |
| CN108439469B (en) * | 2018-02-13 | 2019-12-20 | 浙江大学 | Preparation and application method of silver molybdate nano powder with nearly spherical structure |
| CN111187958A (en) * | 2020-02-19 | 2020-05-22 | 西安交通大学 | Method for preparing nano-lanthanum oxide molybdenum alloy by doping Mo powder/MoO2 and lanthanum molybdate powder |
| CN111187958B (en) * | 2020-02-19 | 2021-01-19 | 西安交通大学 | Mo powder/MoO2Method for preparing nano lanthanum-molybdenum oxide alloy by doping with lanthanum ammonium molybdate powder |
| CN112176236A (en) * | 2020-10-19 | 2021-01-05 | 北京工业大学 | La2O3W-Mo-doped alloy material and preparation method thereof |
| CN113549456A (en) * | 2021-08-18 | 2021-10-26 | 北京工业大学 | A kind of preparation method of multiphase lanthanum molybdate mixed luminescent material without rare earth doping that can emit light at room temperature |
| CN113549456B (en) * | 2021-08-18 | 2023-08-04 | 北京工业大学 | Preparation method of rare earth-free doped room-temperature luminous multiphase lanthanum molybdate mixed luminescent material |
| CN113798504A (en) * | 2021-09-17 | 2021-12-17 | 郑州大学 | Preparation method of rare earth oxide dispersion reinforced tungsten powder for 3D printing |
| CN113798504B (en) * | 2021-09-17 | 2023-08-22 | 郑州大学 | Preparation method of rare earth oxide dispersion reinforced tungsten powder for 3D printing |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1244428C (en) | 2006-03-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1244428C (en) | Method for preparing nm-class composite rare earth molybdenum material by sol-gal process | |
| CN102584231B (en) | Preparation method of ion-doped double perovskite structure tungsten molybdate oxide powder | |
| CN108821777A (en) | Graphene/carbon SiClx composite ceramics and preparation method thereof | |
| CN104328301B (en) | A kind of preparation method of particle-reinforced molybdenum-base composite material | |
| CN101698919B (en) | Particle-reinforced molybdenum-base composite material and preparation method thereof | |
| CN106623960B (en) | A kind of preparation method of zirconium boride dispersion-strengtherning tungsten powder | |
| CN111408714B (en) | Preparation method of graphene reinforced copper-based composite material with dual-scale structure and in-situ growth | |
| CN110256075B (en) | A kind of doping modified Gd2Zr2O7 ceramic material and preparation method thereof | |
| CN108580917B (en) | A method for preparing tungsten dispersion-strengthened copper ultrafine powder by low-temperature combustion synthesis | |
| CN108439977B (en) | A kind of high temperature and low thermal conductivity hafnium oxide-based thermal barrier coating material and preparation method thereof | |
| CN115010491B (en) | A kind of high entropy rare earth tantalate ceramic material and preparation method thereof | |
| CN108946812A (en) | Alkali tungsten bronze nanometer rods and its preparation method and application | |
| CN1341576A (en) | Preparation of high-purity titanium biboride ceramic micropowder by using self-spreading high-temp. reduction synthesis process | |
| CN1300061C (en) | Preparation method of silica alumina gel bonding agent for corundum-mullite composite ceramic | |
| CN110695372B (en) | A kind of preparation method of rare earth element improving copper-graphene interface | |
| CN115448717B (en) | Rare earth-based molybdate high-entropy negative thermal expansion ceramic material and preparation method thereof | |
| CN101066869A (en) | A kind of synthesis method of silicon carbide titanium ceramic powder without TiC impurity phase | |
| CN104326500B (en) | A kind of preparation method of fluffy state nano yttrium oxide powder | |
| CN114671679B (en) | Zirconium pyrophosphate complex phase ceramic material and preparation method thereof | |
| CN111112641A (en) | Preparation method of nano molybdenum-rhenium alloy powder | |
| CN100537083C (en) | Preparation method of Ag composite (Ca0.95Bi0.05)3Co4O9 based oxide thermoelectric material | |
| CN1772610A (en) | Preparation of LaB6 powder by self-propagating metallurgy | |
| CN117532006A (en) | A method for preparing highly dispersed nano-tungsten/rhenium/lanthanum oxide composite powder | |
| CN115894023A (en) | Lamellar Cu @ La assembled from nanoparticles 1/2 Sr 1/2 CoO 3 Preparation method of conductive ceramic powder | |
| CN107573071B (en) | Monodisperse spherical Y2O3And Al2O3Powder preparation (Y)1-xYbx) Method for preparing AG transparent ceramic |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20060308 Termination date: 20100510 |