Iron oxide / neodymium oxide / iron neodymate composite nanowire and preparation method thereof

Abstract

The present invention discloses an iron oxide / neodymium oxide / iron neodymium oxide composite nanowire and a preparation method thereof, belonging to the technical field of composite materials. The composite nanowire is composed of rhombohedral Fe2O3, hexagonal Nd2O3, and orthorhombic FeNdO3 crystal phases; the diameter of the composite nanowire is 20 to 100 nm and the length is greater than 5 μm. The composite nanowire is prepared by placing potassium ferrate, neodymium nitrate, and water into a quartz glass flask, stirring and mixing them uniformly with a magnetic stirrer, and then placing the mixture in an oil bath to react to obtain an iron oxide / neodymium oxide / iron neodymium oxide precursor; the precursor is placed in a corundum crucible to react and finally obtain the composite nanowire. The preparation process of the present invention is easy to control, and the resulting composite nanowire has a large number of catalytically active sites, is expected to have good interface properties and photocatalytic properties, and has good application prospects in the fields of catalysts, electrochemical sensors, and optical devices.

Description

Technical Field

[0001] The present invention belongs to the technical field of composite materials, and in particular relates to an iron oxide / neodymium oxide / iron neodymate composite nanowire and a preparation method thereof. Background Art

[0002] Iron- and neodymium-based nanocomposites are important metal composites with large active surface areas, excellent interfacial properties, catalytic activity, electron transport, magnetic properties, and high chemical and thermal stability. They hold broad application prospects in lithium-ion batteries, supercapacitors, magnetic devices, electrochemical sensors, photocatalytic wastewater treatment, glass, and ceramics. Iron oxide, neodymium oxide, and iron neodymite, as important metal oxide materials, have attracted widespread research interest.

[0003] The national invention patent "Method for Preparing Titanium Dioxide / Iron Oxide Composite Anode Material" (National Invention Patent No.: ZL201510149172.X) discloses a method for preparing a titanium dioxide / iron oxide composite anode material. The raw materials used are titanyl sulfate, ferric chloride, polyvinyl pyrrolidone, and formamide. The material is heated at 500-800°C for 22-26 hours in an air atmosphere. This titanium dioxide / iron oxide composite material has high specific capacity and stable cycling performance. The national invention patent "Graphene / polyaniline / iron oxide composite material for supercapacitors and its preparation method" (National Invention Patent No.: ZL201410221388.8) reports the preparation of a graphene / polyaniline / iron oxide composite material using aniline, graphite oxide, hydrochloric acid, and iron salts (ferric chloride, ferric chloride) as the main raw materials, at 120-180°C for 1-6 hours. This composite material has broad application prospects in supercapacitors, solar cells, and other fields. The national invention patent, "Method for Preparing Neodymium Oxide-Cerium Oxide Composite Nanomaterials" (National Invention Patent Application No. 201010620810.9), reports a method for preparing silicon nitride ceramics through pressureless sintering using cerium oxide and neodymium oxide as additives. The composition comprises 3% to 7% cerium oxide, 5% to 8% neodymium oxide, and 85% to 92% silicon nitride. This method of pressureless sintering silicon nitride ceramics using neodymium oxide and cerium oxide as additives can be applied to the preparation of components in the chemical, mechanical, and aerospace industries. Combining iron oxide with neodymium oxide and iron neodymium oxide to form an iron oxide / neodymium oxide / iron neodymium oxide composite nanomaterial increases the number of catalytically active sites in the composite material, resulting in excellent interfacial and photocatalytic properties. This material has promising applications in catalysts, electrochemical sensors, and optical devices. Summary of the Invention

[0004] The object of the present invention is to provide an iron oxide / neodymium oxide / iron neodymate composite nanowire and a preparation method thereof.

[0005] The present invention is achieved through the following technical solutions.

[0006] The present invention discloses an iron oxide / neodymium oxide / iron neodymate composite nanowire, which is composed of rhombohedral Fe2O3, hexagonal Nd2O3 and orthorhombic FeNdO3 crystal phases; the diameter of the composite nanowire is 20-100nm and the length is greater than 5μm.

[0007] The present invention also provides a method for preparing the above-mentioned iron oxide / neodymium oxide / iron neodymate composite nanowires, which specifically comprises the following steps:

[0008] (1) Potassium ferrate, neodymium nitrate and water are placed in a quartz glass flask, stirred and mixed evenly with a magnetic stirrer, and then placed in an oil bath at a temperature of 100-150° C. for 1-6 hours. The water evaporated during the heating process flows back into the flask through a reflux device. After cooling and drying, an iron oxide / neodymium oxide / iron neodymium oxide precursor is obtained;

[0009] (2) The iron oxide / neodymium oxide / iron neodymium oxide precursor was placed in a corundum crucible, heated to a temperature of 1000-1300°C, kept warm for 5-10 hours, cooled, centrifuged, and washed with ethanol to obtain iron oxide / neodymium oxide / iron neodymium oxide composite nanowires.

[0010] The molar ratio of potassium ferrate to neodymium nitrate is 1:1; the total weight of potassium ferrate and neodymium nitrate accounts for 3-10% of the weight of water; and the total amount of potassium ferrate, neodymium nitrate and water accounts for 50-70% of the filling degree of the flask.

[0011] As an optimization, the total weight of the potassium ferrate and neodymium nitrate accounts for 5% of the weight of water; the total weight of the potassium ferrate, neodymium nitrate and water accounts for 60% of the filling degree of the flask.

[0012] Innovation of the present invention:

[0013] The present invention uses uniform heating in an oil bath. At a certain temperature, potassium ferrate reacts with neodymium nitrate and water to generate a precursor of iron oxide / neodymium oxide / iron neodymate. The precursor of iron oxide / neodymium oxide / iron neodymate reacts at a temperature of 1000-1300°C for 5-10 hours. Under the action of iron oxide and neodymium oxide, iron oxide / neodymium oxide / iron neodymate composite nanowires composed of rhombohedral Fe2O3, hexagonal Nd2O3 and orthorhombic FeNdO3 crystal phases are formed through an oxide-assisted growth process.

[0014] Compared with the prior art, the present invention has the following technical effects:

[0015] 1. The present invention adopts a two-step preparation process, which is easy to control and has good repeatability, providing conditions for the practical application of iron oxide / neodymium oxide / iron neodymate composite nanowires.

[0016] 2. The raw materials used in the present invention are potassium ferrate, neodymium nitrate and water, which do not produce any toxic or harmful gases and are environmentally friendly.

[0017] 3. Iron oxide / neodymium oxide / iron neodymate composite nanowires have a large number of catalytic active sites and are expected to have good interfacial properties and photocatalytic properties, and have good application prospects in catalysts, electrochemical sensors, and optical devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The X-ray diffraction (XRD) pattern of the iron oxide / neodymium oxide / iron neodymate composite nanowires prepared in Example 1;

[0019] According to the JCPDS PDF card, it can be retrieved that the obtained iron oxide / neodymium oxide / iron neodymate composite nanowires are composed of rhombohedral Fe2O3 (JCPDS card, card number: 33~0664), hexagonal Nd2O3 (JCPDS card, card number: 40~1282) and orthorhombic FeNdO3 (JCPDS card, card number: 25~1149) crystal phases.

[0020] Figure 2 This is a scanning electron microscope (SEM) image of the iron oxide / neodymium oxide / iron neodymate composite nanowires prepared in Example 1;

[0021] It can be seen from the figure that the product is composed of nanowires with a diameter of 20 to 100 nm and a length greater than 5 μm.

[0022] Figure 3 Transmission electron microscope (TEM) image of the iron oxide / neodymium oxide / iron neodymate composite nanowires prepared in Example 1 ( Figure 3 (a)) and high-resolution TEM (HRTEM) images ( Figure 3 (b));

[0023] It can be seen from the figure that the product is composed of iron oxide / neodymium oxide / iron neodymate composite nanowires. Some nanowires gather together to form a nanowire bundle morphology. The nanowires are polycrystalline with interplanar spacings of 0.37nm, 0.34nm, and 0.39nm, which correspond to the interplanar spacings of the (012) crystal plane of the rhombohedral Fe2O3 crystal phase, the (100) crystal plane of the hexagonal Nd2O3 crystal phase, and the (101) crystal plane of the orthorhombic FeNdO3 crystal phase, respectively. DETAILED DESCRIPTION

[0024] The present invention is described in detail below with reference to specific embodiments, but the present invention is not limited to the following embodiments.

[0025] Example 1

[0026] (1) Potassium ferrate, neodymium nitrate and water are placed in a quartz glass flask, wherein the molar ratio of potassium ferrate to neodymium nitrate is 1:1, the total weight of potassium ferrate and neodymium nitrate accounts for 10% of the weight of water, and the total amount of potassium ferrate, neodymium nitrate and water accounts for 70% of the filling degree of the flask. After being stirred and mixed uniformly with a magnetic stirrer, the mixture is placed in an oil bath pot and kept at a temperature of 150° C. for 6 hours. The water evaporated during the heating process flows back into the flask through a reflux device. After cooling and drying, an iron oxide / neodymium oxide / iron neodymium oxide precursor is obtained;

[0027] (2) The iron oxide / neodymium oxide / iron neodymium oxide precursor was placed in a corundum crucible, heated to 1300°C, kept warm for 10 hours, cooled, centrifuged, and washed with ethanol to obtain iron oxide / neodymium oxide / iron neodymium oxide composite nanowires.

[0028] Example 2

[0029] (1) Potassium ferrate, neodymium nitrate and water are placed in a quartz glass flask, wherein the molar ratio of potassium ferrate to neodymium nitrate is 1:1, the total weight of potassium ferrate and neodymium nitrate accounts for 3% of the weight of water, and the total amount of potassium ferrate, neodymium nitrate and water accounts for 50% of the filling degree of the flask. After being stirred and mixed evenly with a magnetic stirrer, the mixture is placed in an oil bath at a temperature of 100° C. and kept warm for 1 hour. The water evaporated during the heating process is refluxed into the flask through a reflux device. After cooling and drying, an iron oxide / neodymium oxide / iron neodymium oxide precursor is obtained;

[0030] (2) The iron oxide / neodymium oxide / iron neodymium oxide precursor was placed in a corundum crucible, heated to 1000°C, kept warm for 5 hours, cooled, centrifuged, and washed with ethanol to obtain iron oxide / neodymium oxide / iron neodymium oxide composite nanowires.

[0031] Example 3

[0032] (1) Potassium ferrate, neodymium nitrate and water are placed in a quartz glass flask, wherein the molar ratio of potassium ferrate to neodymium nitrate is 1:1, the total weight of potassium ferrate and neodymium nitrate accounts for 4% of the weight of water, and the total amount of potassium ferrate, neodymium nitrate and water accounts for 55% of the filling degree of the flask. After being stirred and mixed uniformly with a magnetic stirrer, the mixture is placed in an oil bath pot and kept at a temperature of 120°C for 2 hours. The water evaporated during the heating process flows back into the flask through a reflux device. After cooling and drying, an iron oxide / neodymium oxide / iron neodymium oxide precursor is obtained;

[0033] (2) The iron oxide / neodymium oxide / iron neodymium oxide precursor was placed in a corundum crucible, heated to 1100°C, kept warm for 6 hours, cooled, centrifuged, and washed with ethanol to obtain iron oxide / neodymium oxide / iron neodymium oxide composite nanowires.

[0034] Example 4

[0035] (1) Potassium ferrate, neodymium nitrate and water are placed in a quartz glass flask, wherein the molar ratio of potassium ferrate to neodymium nitrate is 1:1, the total weight of potassium ferrate and neodymium nitrate accounts for 5% of the weight of water, and the total amount of potassium ferrate, neodymium nitrate and water accounts for 60% of the filling degree of the flask. After being stirred and mixed evenly with a magnetic stirrer, the mixture is placed in an oil bath at a temperature of 130° C. and kept warm for 3 hours. The water evaporated during the heating process flows back into the flask through a reflux device. After cooling and drying, an iron oxide / neodymium oxide / iron neodymium oxide precursor is obtained;

[0036] (2) The iron oxide / neodymium oxide / iron neodymium oxide precursor was placed in a corundum crucible, heated to 1100°C, kept warm for 7 hours, cooled, centrifuged, and washed with ethanol to obtain iron oxide / neodymium oxide / iron neodymium oxide composite nanowires.

[0037] Example 5

[0038] (1) Potassium ferrate, neodymium nitrate and water are placed in a quartz glass flask, wherein the molar ratio of potassium ferrate to neodymium nitrate is 1:1, the total weight of potassium ferrate and neodymium nitrate accounts for 6% of the weight of water, and the total amount of potassium ferrate, neodymium nitrate and water accounts for 65% of the filling degree of the flask. After being stirred and mixed evenly with a magnetic stirrer, the mixture is placed in an oil bath pot and kept at a temperature of 140°C for 4 hours. The water evaporated during the heating process flows back into the flask through a reflux device. After cooling and drying, an iron oxide / neodymium oxide / iron neodymium oxide precursor is obtained;

[0039] (2) The iron oxide / neodymium oxide / iron neodymium oxide precursor was placed in a corundum crucible, heated to 1200°C, kept warm for 8 hours, cooled, centrifuged, and washed with ethanol to obtain iron oxide / neodymium oxide / iron neodymium oxide composite nanowires.

[0040] Example 6

[0041] (1) Potassium ferrate, neodymium nitrate and water are placed in a quartz glass flask, wherein the molar ratio of potassium ferrate to neodymium nitrate is 1:1, the total weight of potassium ferrate and neodymium nitrate accounts for 7% of the weight of water, and the total amount of potassium ferrate, neodymium nitrate and water accounts for 70% of the filling degree of the flask. After being stirred and mixed uniformly with a magnetic stirrer, the mixture is placed in an oil bath pot and kept at a temperature of 140°C for 5 hours. The water evaporated during the heating process flows back into the flask through a reflux device. After cooling and drying, an iron oxide / neodymium oxide / iron neodymium oxide precursor is obtained;

[0042] (2) The iron oxide / neodymium oxide / iron neodymium oxide precursor was placed in a corundum crucible, heated to 1200°C, kept warm for 9 hours, cooled, centrifuged, and washed with ethanol to obtain iron oxide / neodymium oxide / iron neodymium oxide composite nanowires.

[0043] Example 7

[0044] (1) Potassium ferrate, neodymium nitrate and water are placed in a quartz glass flask, wherein the molar ratio of potassium ferrate to neodymium nitrate is 1:1, the total weight of potassium ferrate and neodymium nitrate accounts for 8% of the weight of water, and the total amount of potassium ferrate, neodymium nitrate and water accounts for 65% of the filling degree of the flask. After being stirred and mixed uniformly with a magnetic stirrer, the mixture is placed in an oil bath pot and kept at a temperature of 130°C for 5 hours. The water evaporated during the heating process flows back into the flask through a reflux device. After cooling and drying, an iron oxide / neodymium oxide / iron neodymium oxide precursor is obtained;

[0045] (2) The iron oxide / neodymium oxide / iron neodymium oxide precursor was placed in a corundum crucible, heated to 1250°C, kept warm for 8 hours, cooled, centrifuged, and washed with ethanol to obtain iron oxide / neodymium oxide / iron neodymium oxide composite nanowires.

[0046] Example 8

[0047] (1) Potassium ferrate, neodymium nitrate and water are placed in a quartz glass flask, wherein the molar ratio of potassium ferrate to neodymium nitrate is 1:1, the total weight of potassium ferrate and neodymium nitrate accounts for 9% of the weight of water, and the total amount of potassium ferrate, neodymium nitrate and water accounts for 60% of the filling degree of the flask. After being stirred and mixed uniformly with a magnetic stirrer, the mixture is placed in an oil bath pot and kept at a temperature of 120°C for 5 hours. The water evaporated during the heating process flows back into the flask through a reflux device. After cooling and drying, an iron oxide / neodymium oxide / iron neodymium oxide precursor is obtained;

[0048] (2) The iron oxide / neodymium oxide / iron neodymium oxide precursor was placed in a corundum crucible, heated to 1250°C, kept warm for 9 hours, cooled, centrifuged, and washed with ethanol to obtain iron oxide / neodymium oxide / iron neodymium oxide composite nanowires.

Claims

1. A method for preparing iron oxide / neodymium oxide / iron neodymate composite nanowires, characterized in that: The iron oxide / neodymium oxide / iron neodymate composite nanowires are composed of rhombohedral Fe2O3, hexagonal Nd2O3 and orthorhombic FeNdO3 crystal phases; the diameter of the composite nanowires is 20 to 100 nm and the length is greater than 5 μm; The preparation of the iron oxide / neodymium oxide / iron neodymate composite nanowires comprises the following steps: (1) Potassium ferrate, neodymium nitrate and water were placed in a quartz glass flask, stirred and mixed evenly with a magnetic stirrer, and then placed in an oil bath at a temperature of 100-150°C for 1-6 hours. The evaporated water during the heating process was refluxed back into the flask through a reflux device. After cooling and drying, an iron oxide / neodymium oxide / iron neodymium oxide precursor was obtained. (2) The iron oxide / neodymium oxide / iron neodymium oxide precursor was placed in a corundum crucible, heated to a temperature of 1000-1300°C, kept warm for 5-10 hours, cooled, centrifuged, and washed with ethanol to obtain iron oxide / neodymium oxide / iron neodymium oxide composite nanowires; The molar ratio of potassium ferrate to neodymium nitrate is 1:1; The total weight of the potassium ferrate and neodymium nitrate accounts for 3-10% of the weight of water; The total amount of potassium ferrate, neodymium nitrate and water accounts for 50-70% of the filling degree of the flask.

2. The method for preparing the iron oxide / neodymium oxide / iron neodymate composite nanowires according to claim 1, wherein: The total weight of the potassium ferrate and neodymium nitrate accounts for 5% of the weight of water; The total amount of potassium ferrate, neodymium nitrate and water accounts for 60% of the filling degree of the flask.

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