Metal oxide (at) ZTC composite nanomaterial and application thereof in catalysis of thermal decomposition of ammonium perchlorate

Abstract

The invention discloses a metal oxide (at) ZTC composite nanomaterial and application thereof in catalysis of thermal decomposition of ammonium perchlorate, and belongs to the technical field of nanostructure materials. The invention provides a metal oxide doped nano ZTC and a method for catalyzing decomposition of ammonium perchlorate by using the metal oxide doped nano ZTC. Nanometer ZTC doped with different metal oxides is added into ammonium perchlorate to serve as a catalyst, the thermal decomposition reaction of ammonium perchlorate is promoted, and the purpose of reducing the thermal decomposition temperature of ammonium perchlorate is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of nanostructured materials, and in particular relates to a method for catalyzing the thermal decomposition of ammonium perchlorate by using metal oxide-doped nano-template carbon. Background Art

[0002] In recent years, nanomaterials including carbon materials, metals, alloys and transition metal oxides have shown excellent catalytic performance in the thermal decomposition of ammonium perchlorate (AP). Transition metal particles have nanoscale size, a large number of lattice defects and a large number of coordinated unsaturated atoms on their surface, and have great potential in promoting the decomposition of AP. Transition metal oxides show excellent catalytic activity in the thermal decomposition of AP, among which Fe, Zn and Cu show good AP thermal decomposition catalytic performance due to their unique electron transfer properties derived from 3d orbitals and abundant surface defects. However, metal oxides are prone to agglomeration during the catalytic process. The present invention loads the metal oxide on a carrier with a high specific surface area, which increases the contact area with AP and improves the catalytic effect.

[0003] Carbon materials have excellent chemical stability, high electron mobility, strong adsorption capacity, high specific surface area and easy modification, so they are often used as substrate materials for fixing various metal nanoparticles. They can retain metal catalytic active sites at the microscopic level, limit the distribution of nanoparticles and reduce agglomeration, thereby significantly improving the catalytic performance of AP. However, the widespread application of carbon materials as burning rate catalysts in the field still encounters major challenges. The main obstacle comes from the high cost of materials such as carbon nanotubes and graphene, and the large-scale production and preparation that has not yet been achieved. In addition, due to the large specific surface area of ​​carbon materials, more binders are required, which in turn reduces the solid content of the propellant and has an adverse effect on its energy performance. Therefore, the development of nanocarbon substrate materials with high catalytic activity and large-scale preparation is a promising research direction.

[0004] In recent years, zeolite template carbon (ZTC) materials that can be prepared on a large scale have become a research hotspot in material design. ZTC has a three-dimensional single-layer curved graphene structure, mainly composed of four-membered rings, five-membered rings, six-membered rings and seven-membered rings, and has a large number of SP 3 The structure has edge defect carbon structure and the specific surface area can be as high as 4000m 2 However, there is no report on the use of ZTC as a defective carbon material to prepare supported transition metal nanoparticle catalysts for catalytic AP decomposition. Summary of the invention

[0005] In view of the defects existing in the above-mentioned prior art, in order to solve the problems that nanocarbon as a base material for fixing various metal nanoparticles is high in cost, cannot be mass-produced, and has limited catalytic effect, the purpose of the present invention is to design and provide a metal oxide-doped nano ZTC and its application and method in catalyzing AP decomposition, a method for promoting AP decomposition by metal oxide @ ZTC composite nanomaterials, which is added to AP to carry out thermal decomposition reaction of AP to achieve the purpose of lowering the thermal decomposition temperature and increasing the heat release, providing a new idea for the application of other types of oxides in thermal catalysis.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] In one aspect, the present invention provides a metal oxide@ZTC composite nanomaterial, comprising nano ZTC and metal oxide filled in the pores of the nano ZTC.

[0008] The metal oxide doped nano ZTC composite material, the metal oxide is Fe 2 O 3 、ZnO、CuO、Cu 2 O, Cu 2+1 O、MnO 2 , one of CoO, NiO, CaO or MgO.

[0009] In a second aspect, the present invention provides a method for preparing the metal oxide-doped nano ZTC composite material, comprising the following steps:

[0010] (1) weighing a metal nitrate compound and dissolving it in dilute nitric acid to obtain a solution 1;

[0011] (2) Weigh nano ZTC, dissolve it in water, add a surfactant, and stir to obtain solution 2;

[0012] (3) adding the above solution 1 to solution 2, stirring to dissolve, adjusting the pH to 8.5-10.5, stirring at room temperature and then raising the temperature, and continuing stirring to obtain a precursor solution;

[0013] (4) filtering the precursor solution obtained above, washing, drying, grinding, and calcining under a nitrogen or inert gas atmosphere to obtain a metal oxide@ZTC composite nanomaterial.

[0014] The preparation method, the metal nitrate compound is Fe(NO 3 ) 3 9H 2 O、Zn(NO 3 ) 2 6H 2 O, Cu(NO3 ) 2 6H 2 O、Mn(NO 3 ) 2 6H 2 O、Co(NO 3 ) 2 6H 2 O.Ni(NO 3 ) 2 6H 2 O, Ca(NO 3 ) 2 ·4H 2 O or Mg(NO 3 ) 2 6H 2 O.

[0015] The metal ion concentration in the solution 1 is 5-10 mmol / L.

[0016] The specific preparation method of the nano ZTC in step (2) is as follows:

[0017] The zeolite template is placed in a tube furnace and heated in a pure nitrogen or inert gas atmosphere, the pure nitrogen or inert gas is turned off, a carbon source is introduced, deposition is performed, the temperature is increased for heating, and after cooling to room temperature, a mixed solution of HCl and HF is added, stirred, acid washed, filtered, washed to neutrality, and dried to obtain nano ZTC.

[0018] In the preparation method, the zeolite template is NaX or NaY zeolite;

[0019] Preferably, the zeolite template is NaX zeolite;

[0020] The conditions for the heating treatment in a pure nitrogen or inert gas atmosphere are: a flow rate of pure nitrogen or inert gas of 200-1000 mL / min, a heating rate of 2-10° C. / min, and heating to 550-650° C.;

[0021] The carbon source is 2%-5% C 2 H 2 Mixed gas with pure nitrogen or inert gas, or 2%-5% C 3 H 6 Mixed gas with pure nitrogen or inert gas;

[0022] The deposition conditions are: flow rate 200-1000 mL / min, temperature 550-650° C., time 3-6 h;

[0023] The conditions for heating the sample by increasing the temperature are as follows: heating rate 2-10°C / min, heating to 800-900°C, and maintaining the temperature in a pure nitrogen or inert gas atmosphere for 2-4 hours;

[0024] The stirring time is 6-12h;

[0025] The concentration of HCl is 5-10 wt %, and the concentration of HF is 5-10 wt %.

[0026] In the preparation method, the surfactant is polyethylene glycol or ethanol;

[0027] The conditions for raising the temperature after stirring at room temperature in step (3) are: stirring at 25-35° C. for 1-2 h, and then stirring at 80-95° C. for 1-2 h;

[0028] The calcination conditions are: calcination temperature 450-550° C., calcination time 1-3 h.

[0029] In a third aspect, the present invention provides the use of the metal oxide @ ZTC composite nanomaterial, or the metal oxide @ ZTC composite nanomaterial obtained by any one of the preparation methods described in catalyzing the thermal decomposition of ammonium perchlorate.

[0030] In a fourth aspect, the present invention provides a method for decomposing ammonium perchlorate, comprising weighing the metal oxide@ZTC composite nanomaterial, adding it to ammonium perchlorate, and performing thermal decomposition.

[0031] In the decomposition method, the metal oxide@ZTC composite nanomaterial accounts for 1-5% of the mass of ammonium perchlorate.

[0032] The metal oxide is Fe 2 O 3 , the synthetic compound is Fe 2 O 3 @ When the doping amount of ZTC is 5%, that is, 5% Fe 2 O 3 @ZTC catalyst can reduce the high temperature decomposition peak of AP by 27℃ and 52℃ respectively.

[0033] When the metal oxide is ZnO and the compound is ZnO@ZTC with a doping amount of 5%, the high temperature decomposition peaks of AP can be reduced by 35° C. and 89° C. respectively using 5% ZnO@ZTC catalyst.

[0034] The metal oxide is Cu 2+1 O, the composite is Cu 2+1 When the doping amount of O@ZTC is 5%, that is, 5% Cu 2+ 1O@ZTC catalyst can reduce the high temperature decomposition peak of AP by 130℃.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] ZTC materials have abundant intrinsic defect carbon, which can accelerate the initial decomposition of AP. Adding 5% ZTC can reduce the high-temperature decomposition peak of AP by 46°C. After compounding with metal oxides, the catalytic performance of ZTC-based composite materials on AP is further improved. 2 O 3 @ZTC and 1% ZnO@ZTC catalysts, the high temperature decomposition peak of AP decreased by 39℃ and 76℃, respectively. When the ratio of the two catalysts increased to 5%, the high temperature decomposition peak of AP decreased by 52℃ and 89℃, respectively. 2+1 The O@ZTC sample has the best catalytic performance with only 1% Cu addition 2+1 O@ZTC can reduce the high-temperature decomposition temperature of AP by 122°C. 2+1 O@ZTC can reduce the high temperature decomposition temperature of AP by 130℃. 2+1 During the preparation of O@ZTC catalyst, the defective carbon structure of ZTC can in situ reduce Cu 2+ Cu 2+1 O and Cu, Cu 2+1 O and Cu play an important role in improving the thermal decomposition performance of AP. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 The Fe prepared in Example 1 of the present invention 2 O 3 @ZTC’s X-ray diffraction spectrum;

[0038] Figure 2 This is the X-ray diffraction spectrum of ZnO@ZTC prepared in Example 2 of the present invention;

[0039] Figure 3 The Cu prepared in Example 3 of the present invention 2+1 X-ray diffraction spectrum of O@ZTC;

[0040] Figure 4 The Cu prepared in Example 3 of the present invention 2+1 SEM image of O@ZTC;

[0041] Figure 5 is the DSC graph of pure AP;

[0042] Figure 6 DSC diagram of 5% ZTC-AP;

[0043] Figure 71%Fe 2 O 3 @ZTC-DSC diagram of AP;

[0044] Figure 8 5%Fe 2 O 3 @ZTC-DSC diagram of AP;

[0045] Fig. 9 DSC diagram of 1% ZnO@ZTC-AP;

[0046] Fig.10 DSC diagram of 5% ZnO@ZTC-AP;

[0047] Fig.11 1%Cu 2+1 DSC graph of O@ZTC-AP;

[0048] Fig.12 5%Cu 2+1 DSC graph of O@ZTC-AP. DETAILED DESCRIPTION

[0049] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings and embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] Embodiment 1:

[0051] (1) 10 g of NaX zeolite was placed in a tube furnace and heated to 600 °C at a heating rate of 2 °C / min in an inert gas atmosphere with a flow rate of 200 mL / min;

[0052] (2) Turn off the inert gas and use 2% C 2 H 2 (The rest is N 2 ), the flow rate is 200 mL / min, and the deposition process is maintained at 600 °C for 5 h;

[0053] (3) The sample was further heated to 800°C at a rate of 2°C / min and maintained in an inert gas atmosphere for 3 h;

[0054] (4) adding the obtained carbon and zeolite mixture into 500 mL of HCl / HF (10 / 30 wt%) solution and stirring for 12 h, and acid washing to remove the zeolite template;

[0055] (5) Filter the solution, wash the sample with deionized water until it is neutral, and dry it at 100° C. for 12 h to prepare a ZTC sample;

[0056] (6) Take 136.4 mg of Fe(NO 3 ) 3 9H 2 O were washed with 50 mL 5% diluted HNO 3 Dissolve to obtain solution 1, wherein the metal ion concentration is 6.76mmol / L;

[0057] (7) 50 mg ZTC powder was dispersed in 40 mL deionized water in a beaker, and then 5 mL PEG-400 was added as a surfactant and stirred for 1 h to obtain solution 2;

[0058] (8) Then, the above solution 1 was added to solution 2 and stirred at 25°C for 1 hour to obtain solution 3. Diluted NaOH solution (1 g NaOH, 80 mL water) was added dropwise to solution 3 to adjust the pH value of the mixture to 10.5;

[0059] (9) Then continue stirring at 25°C for 1 h;

[0060] (10) Then stirred at 95 °C for 1 h;

[0061] (11) The final precursor was filtered, washed, dried, and ground, and then calcined at 500 °C for 2 h under an inert gas atmosphere to obtain Fe 2 O 3 @ZTC composite nanopowder. The Fe 2 O 3 @ZTC composite nanopowder X-ray diffraction spectrum Figure 1 shown. Figure 1 The sharp peaks in the figure indicate that the metal oxide nanoparticles in the catalyst material are well crystallized, while the broad peaks clearly indicate the presence of small-sized nanocrystals in the sample. 2 O 3 Standard card (JCPDS#39-1346) for comparison, Fe 2 O 3 The characteristic peaks of @ZTC sample at 2θ=30.24°, 35.63°, 43.28°, 53.73°, 57.27° and 62.93° are consistent with the standard card, representing γ-Fe (220), (311), (222), (400), (422), (511), (440) and (533), respectively. 2 O 3 Characteristic peak. The position and relative intensity of the peak are consistent with the structure of hematite, confirming that γ-Fe 2 O 3Successful doping of nanocrystals in ZTC samples.

[0062] Embodiment 2:

[0063] The ZTC powder sample preparation process is the same as steps (1) to (5) in Example 1 and will not be repeated here;

[0064] (1) Take 100.6 mg of Zn(NO 3 ) 2 6H 2 O were washed with 50 mL 5% diluted HNO 3 Dissolve to obtain solution 1, wherein the metal ion content is 6.76mmol / L;

[0065] (2) 50 mg ZTC powder was dispersed in 40 mL deionized water in a beaker, and then 5 mL PEG-400 was added as a surfactant and stirred for 1 h to obtain solution 2;

[0066] (3) Then, the above solution 1 was added to solution 2 and stirred at 25°C for 1 hour to obtain solution 3. Diluted NaOH solution (1 g NaOH, 80 mL water) was added dropwise to solution 3 to adjust the pH value of the mixture to 10.5;

[0067] (4) Then continue stirring at 25°C for 1 h;

[0068] (5) Then stir at 95°C for 1 h;

[0069] (6) The final precursor was filtered, washed, dried and ground, and then calcined at 350°C for 2 h under an inert gas atmosphere to obtain ZnO-ZTC composite nanopowder. The X-ray diffraction spectrum of the ZnO-ZTC composite nanopowder is shown in Figure 2 As shown in the figure, after comparison with the ZnO standard card (JCPDS#36-1451), the characteristic peaks at 2θ=31.77°, 34.42°, 36.25°, 47.54°, 56.60°, 66.38°, 67.96° and 69.10 in the ZnO@ZTC sample are consistent with the standard card, representing the characteristic peaks of the (100), (002), (101), (102), (110), (103), (112) and (201) crystal planes of ZnO. All diffraction peaks correspond to the hexagonal wurtzite structure of ZnO, excluding the possibility of impurities, confirming that ZTC samples are successfully doped with ZnO nanocrystals.

[0070] Embodiment 3:

[0071] The ZTC powder sample preparation process is the same as steps (1) to (5) in Example 1 and will not be repeated here;

[0072] (1) Take 100.1 mg of Cu(NO 3 ) 2 6H 2 O were washed with 50 mL 5% diluted HNO 3 Dissolve to obtain solution 1, wherein the metal ion content is 6.76mmol / L;

[0073] (2) 50 mg ZTC powder was dispersed in 40 mL deionized water in a beaker, and then 5 mL PEG-400 was added as a surfactant and stirred for 1 h to obtain solution 2;

[0074] (3) Then, the above solution 1 was added to solution 2 and stirred at 25°C for 1 hour to obtain solution 3. Diluted NaOH solution (1 g NaOH, 80 mL water) was added dropwise to solution 3 to adjust the pH value of the mixture to 10.5;

[0075] (4) Then continue stirring at 25°C for 1 h;

[0076] (5) Then stir at 65°C for 1 h;

[0077] (6) The final precursor was filtered, washed, dried, and ground, and then calcined at 250 °C for 2 h under an inert gas atmosphere to obtain Cu 2+1 O@ZTC composite nanopowder. 2+1 The X-ray diffraction spectrum of O@ZTC composite nanopowder is shown in Figure 3 As shown, with Cu 2+1 OO standard card (JCPDS#05-0667), Cu 2+1 The characteristic peaks of O@ZTC sample at 2θ=36.42°, 42.30°, 61.34° and 73.32° are consistent with the standard card, representing Cu 2+1 The characteristic peaks of the (111), (200), (220) and (311) crystal planes of O. In addition, Cu 2+1 The O@ZTC sample also exhibits obvious characteristic peaks at 2θ=43.29°, 50.43° and 74.13°. Compared with Cu (JCPDS04-0836), the diffraction peaks are consistent with Cu (111), (200) and (220). 2+1 O composition, Cu 2+1 O represents Cu with excess metal defects 2 O. The results show that during the preparation process, the edge unsaturated carbon defects of ZTC catalyze the metal excess defect Cu 2+1 Synthesis of O, Cu 2+1 O is embedded in the microporous carbon framework of ZTC.

[0078] Figure 4 Cu 2+1 SEM image of O@ZTC sample and EDS images of Cu, O, and C elements. The SEM image shows that ZTC is composed of octahedral crystals similar to the original morphology of zeolite crystals. 2+1 O loading, its outer surface is rough and covered with tiny particles. In addition, EDX element mapping images confirm the uniform distribution of Cu and O atoms in ZTC, indicating that Cu 2+1 O is uniformly doped on the surface of ZTC.

[0079] Comparative Example 1:

[0080] Weigh ZTC and AP in a mass ratio of 5:95, mix them, place them in a mortar and grind them for 15-30 minutes to obtain a 5% ZTC-AP sample. Use a thermogravimetric analyzer to conduct a pyrolysis experiment to evaluate the performance of the ZTC catalyst. The specific operation is as follows:

[0081] 5-10 mg of pure AP or 5% ZTC-AP sample was placed in a crucible, and the temperature was raised from 25°C to 550°C in a nitrogen atmosphere at a heating rate of 2-10°C / min, and the TG / DTG and DSC curves were measured.

[0082] The results are as follows Figure 5 As shown in Figure 2, an endothermic peak of AP is found at 239°C, which is caused by the lattice transformation of AP. The other three exothermic peaks are at 288°C, 375°C and 442°C, representing the decomposition exotherm of AP in the low-temperature phase and the high-temperature phase, respectively.

[0083] Figure 6 The DSC curve of 5% ZTC-AP decomposition shows an endothermic peak at 238°C, indicating that 5% ZTC catalyst does not affect the lattice transformation of AP. The high-temperature decomposition peaks decreased from 375°C and 442°C to 358°C and 396°C, respectively, down 17°C and 46°C, indicating that ZTC has a certain catalytic effect on the decomposition of AP.

[0084] Embodiment 4:

[0085] 1. Weigh 1 mg of Fe prepared in Example 1 above. 2 O 3 @ZTC, mixed with 99mgAP, ground in a mortar for 15-30min, to obtain 1%Fe 2 O 3 @ZTC-AP sample;

[0086] Weigh 5 mg of Fe prepared in Example 1 above 2 O 3 @ZTC, mixed with 95mgAP, ground in a mortar for 15-30min to obtain 5%Fe2 O 3 @ZTC-AP sample;

[0087] Weigh 1 mg of the ZnO@ZTC prepared in Example 2 above, mix it with 99 mg of AP, and grind it in a mortar for 15-30 min to obtain a 1% ZnO@ZTC-AP sample;

[0088] Weigh 5 mg of the ZnO@ZTC prepared in Example 2 above, mix it with 95 mg of AP, and grind it in a mortar for 15-30 min to obtain a 5% ZnO@ZTC-AP sample;

[0089] Weigh 1 mg of Cu prepared in Example 3 above 2+1 O@ZTC was mixed with 99 mg AP and ground in a mortar for 15-30 min to obtain 1% Cu 2+1 O@ZTC-AP sample;

[0090] Weigh 5 mg of Cu prepared in Example 3 above 2+1 O@ZTC was mixed with 95 mg AP and ground in a mortar for 15-30 min to obtain 5% Cu 2+1 O@ZTC-AP sample.

[0091] 2. Use a thermogravimetric analyzer to carry out a pyrolysis experiment to evaluate the performance of the catalyst. The specific operations are as follows:

[0092] 5-10 mg of the samples prepared above were respectively taken and placed in a crucible, and the temperature was raised from 25° C. to 550° C. under a nitrogen atmosphere at a heating rate of 10° C. / min, and the TG / DTG and DSC curves were measured.

[0093] Figure 7 1% Fe shown 2 O 3 @ZTC-AP sample decomposition DSC curve. It can be seen that an endothermic peak appears at 238°C, indicating that 1% Fe 2 O 3 @ZTC catalyst does not affect AP lattice transformation. Compared with pure AP ( Figure 5 ), 1%Fe 2 O 3 The high-temperature pyrolysis peaks of @ZTC-AP decreased from 375°C and 442°C to 345°C and 403°C, respectively, with decreases of 30°C and 39°C.

[0094] Figure 8 5%Fe 2 O 3 @ZTC-AP sample decomposition DSC curve, an endothermic peak appears at 238 ° C, indicating that 5% Fe 2 O 3The other two exothermic peaks at 348℃ and 390℃ further indicate that the addition of 5% Fe 2 O 3 @ZTC has a significant catalytic effect on the decomposition of AP, and the high-temperature decomposition peak temperatures of AP are reduced by 27℃ and 52℃, respectively.

[0095] Fig. 9 The DSC curve of the decomposition of 1% ZnO@ZTC-AP sample is shown. The addition of 1% ZnO@ZTC has a significant catalytic effect on the decomposition of AP, reducing the high-temperature decomposition peak temperature by 44°C and 76°C, respectively.

[0096] Fig.10 The DSC curves of the decomposition of 5% ZnO@ZTC-AP samples are shown in Figure 2. The low-temperature decomposition peak of 5% ZnO@ZTC-AP sample is 286°C, which is 8°C lower than that of 1% ZnO@ZTC-AP sample, and the high-temperature decomposition peaks are 340°C and 353°C, which are 35°C and 89°C lower than AP.

[0097] Fig.11 1%Cu 2+1 DSC curve of O@ZTC-AP sample decomposition. An endothermic peak appears at 238℃, indicating that 1% Cu 2+1 O@ZTC catalyst has no effect on AP lattice transformation. Its low temperature decomposition peak is 287℃, which shows that it has almost no effect on the low temperature decomposition of AP. The high temperature decomposition peak is reduced from 375℃ and 442℃ to 310℃ and 320℃, which is a decrease of 65℃ and 122℃. It further shows that adding 1% Cu 2+1 O@ZTC has a significant catalytic effect on the decomposition of AP.

[0098] Fig.12 5%Cu 2+1 The DSC curve of the decomposition of the O@ZTC-AP sample shows that the low-temperature decomposition peak of the sample is 280°C, which is 7°C lower than that of the pure AP sample. The high-temperature decomposition peaks merge into a single peak at 312°C, which is 130°C lower than that of the pure AP sample.

[0099] In summary, the Cu prepared by the present invention 2+1 O@ZTC catalyst has strong AP catalytic performance, especially in reducing the initial decomposition temperature of AP.

[0100] The above specific implementation method part specifically introduces the analytical method involved in the present invention. It should be noted that the above introduction is only to help those skilled in the art better understand the method and ideas of the present invention, rather than limiting the relevant content. Without departing from the principle of the present invention, those skilled in the art may also make appropriate adjustments or modifications to the present invention, and the above adjustments and modifications shall also fall within the scope of protection of the present invention.

Claims

1. A metal oxide @ ZTC composite nanomaterial, characterized in that: The invention comprises nano ZTC and metal oxide filled in the pores of the nano ZTC.

2. The metal oxide-doped nano ZTC composite material according to claim 1, characterized in that: The metal oxide is Fe2O3, ZnO, CuO, Cu2O, Cu 2+1 One of O, MnO2, CoO, NiO, CaO or MgO.

3. The method for preparing a metal oxide-doped nano ZTC composite material according to claim 1 or 2, characterized in that: The following steps are involved: (1) Weigh a metal nitrate compound and dissolve it in dilute nitric acid to obtain a solution 1; (2) Weigh nano ZTC, dissolve it in water, add a surfactant, and stir to obtain solution 2; (3) adding the above solution 1 to solution 2, stirring to dissolve, adjusting the pH to 8.5-10.5, stirring at room temperature and then raising the temperature, and continuing stirring to obtain a precursor solution; (4) filtering the precursor solution obtained above, washing, drying, grinding, and calcining under a nitrogen or inert gas atmosphere to obtain a metal oxide@ZTC composite nanomaterial.

4. The preparation method according to claim 3, characterized in that: The metal nitrate compound is Fe(NO3)3·9H2O, Zn(NO3)2·6H2O, Cu(NO3)2·6H2O, Mn(NO3)2·6H2O, Co(NO3)2·6H2O, Ni(NO3)2·6H2O, Ca(NO3)2·4H2O or Mg(NO3)2·6H2O; The metal ion concentration in the solution 1 is 5-10 mmol / L.

5. The preparation method according to claim 3, characterized in that: The specific preparation method of the nano ZTC in step (2) is: The zeolite template is placed in a tube furnace and heated in a pure nitrogen or inert gas atmosphere, the pure nitrogen or inert gas is turned off, a carbon source is introduced, deposition is performed, the temperature is increased for heating, and after cooling to room temperature, a mixed solution of HCl and HF is added, stirred, acid washed, filtered, washed to neutrality, and dried to obtain nano ZTC.

6. The preparation method according to claim 5, characterized in that: The zeolite template is NaX type or NaY zeolite; Preferably, the zeolite template is NaX zeolite; The conditions for the heating treatment in a pure nitrogen or inert gas atmosphere are: a pure nitrogen or inert gas flow rate of 200-1000 mL / min, a heating rate of 2-10° C. / min, and heating to 550-650° C.; The carbon source is a mixed gas of 2%-5% C2H2 and pure nitrogen or an inert gas, or a mixed gas of 2%-5% C3H6 and pure nitrogen or an inert gas; The deposition conditions are: flow rate 200-1000 mL / min, temperature 550-650° C., time 3-6 h; The conditions for heating the material at elevated temperature are as follows: heating rate 2-10°C / min, heating to 800-950°C, and maintaining the temperature in pure nitrogen or inert gas atmosphere for 2-4 hours; The stirring time is 6-12h; The concentration of HCl is 5-10 wt%; The concentration of HF is 5-10 wt%.

7. The preparation method according to claim 3, characterized in that: The surfactant is polyethylene glycol or ethanol; The conditions for raising the temperature after stirring at room temperature in step (3) are: stirring at 25-35° C. for 1-2 h, and then stirring at 80-95° C. for 1-2 h; The calcination conditions are: calcination temperature 450-550° C., calcination time 1-3 h.

8. Use of the metal oxide @ ZTC composite nanomaterial as claimed in claim 1 or 2, or the metal oxide @ ZTC composite nanomaterial obtained by the preparation method as claimed in any one of claims 1 to 7 in catalyzing the thermal decomposition of ammonium perchlorate.

9. A method for decomposing ammonium perchlorate, characterized in that: Weigh the metal oxide@ZTC composite nanomaterial as claimed in claim 1 or 2, add it into ammonium perchlorate, and perform thermal decomposition.

10. The decomposition method according to claim 9, characterized in that: The metal oxide@ZTC composite nanomaterial accounts for 1-5% of the mass of ammonium perchlorate.

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