CN103553150B - Preparation method of Co-Fe LDH (layered double hydroxide) - Google Patents

Preparation method of Co-Fe LDH (layered double hydroxide) Download PDF

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CN103553150B
CN103553150B CN201310465245.7A CN201310465245A CN103553150B CN 103553150 B CN103553150 B CN 103553150B CN 201310465245 A CN201310465245 A CN 201310465245A CN 103553150 B CN103553150 B CN 103553150B
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hydrate
fecl
cocl
reaction solution
preparation
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CN103553150A (en
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王银玲
李发骏
焦守峰
李茂国
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Anhui Normal University
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Anhui Normal University
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Abstract

The invention discloses a preparation method of Co-Fe LDH (layered double hydroxide). The preparation method comprises the following steps: (1) stirring CoCl2 hydrate and FeCl2 hydrate with water for mixing to obtain a mixed solution; and (2) under stirring and sealing conditions, successively adding the mixed solution and an alkaline buffer agent to a reactor to obtain a reaction solution, heating up to 100-120 DEG C for reaction for 3-5h, and contacting the reaction system with air for cooling to 20-30 DEG C. The molar concentration of the CoCl2 hydrate in the reaction solution is 0.0067-0.0333mol / L; the molar concentrations of the FeCl2 hydrate in the reaction solution is 0.0033-0.0167mol / L; and the molar concentration ratio of the CoCl2 hydrate to the FeCl2 hydrate in the reaction solution is (10:1)-(2:5). The preparation method has the advantages of simple operation and high crystallinity, and can greatly improve the yield of the product.

Description

The preparation method of Co-Fe LDH
Technical field
The present invention relates to the preparation method of a kind of Co-Fe LDH.
Background technology
Layered double-hydroxide (LDH) material is mainly by salt and alkali reaction, and salt and oxide compound react and ion exchange reaction obtains.In theory, as long as divalent ion radius and Mg 2+radius close, be not too little or too large, the radius of trivalent ion and Al 3+radius is close, can with the Mg on laminate 2+, Al 3+isomorphous substitution, obtains the houghite of laminate structure, and therefore, the kind of double-hydroxide cannot be estimated in theory.According to its component feature, according between laminate whether containing variable valency metal ions, LDH can be divided into have electroactive, electroactive little and without electroactive three classes.And electroactive LDH has the range of application widening LDH to a certain extent, therefore become the focus of research in recent years.
We know, structure and pattern are one of principal elements affecting material property, and therefore, the layered double-hydroxide of synthesis high-crystallinity has great importance to its physico-chemical property of research.Find through literature survey, the pattern of employing Co deposited synthesis is homogeneous and the LDH material that degree of crystallinity is high is all generally Al 3+base LDH, as Mg-Al LDH, Co-Al, Fe-Al or even ternary M-M '-Al LDH.The composition of the main body laminate of layered double-hydroxide has adjustable sex change, and main body laminate composition changes, and its performance also can change thereupon.Therefore, in LDH main body laminate, introduce transition metal ion, expect that the characteristics such as its potential optical, electrical, magnetic can give the performance of some uniquenesses of LDH.
But, so far, about non-Al 3+the report of base LDH, especially structure and pattern good transition metal base LDH is less.In order to obtained desirable transition metal based hydrotalcite, research worker both domestic and external has done a large amount of exploration work: the people such as Ma adopt homogeneous co-precipitation process to synthesize stratiform Co 2+-Fe 2+lDH, then at CHCl 3in use I 2by Fe 2+be oxidized to Fe 3+, finally obtain the Co of hexagon high-crystallinity 2+-Fe 3+lDH, this seminar adopts again same local synthesis oxidation style to obtain the higher single double hydroxide Co of degree of crystallinity subsequently 2+-Co 3+lDH.But the synthesis condition of these synthetic methods is extremely harsh, be difficult in laboratory repeat, major cause is that the absolute anaerobic in the aqueous solution is difficult to reach.The people such as Liu do sequestrant with trisodium citrate, adopt ureal antigen to synthesize the good Ni of pattern 2+-Fe 3+layered double-hydroxide, this method is difficult to be generalized to other divalent ion as contained Co 2+lDH synthesis.
Document J.AM.CHEM.SOC.2011,133, P613-620:Topochemical Synthesisof Co-Fe Layered DoubleHydroxides at Varied Fe/Co Ratios:UniqueIntercalation of Triiodide and Its Profound Effect discloses the preparation method of Co-Fe LDH: by CoCl 26H 2o, FeCl 24H 2o deionized water is dissolved in three-necked flask, adds hexamethylenetetramine (HMT) after strict deoxygenation, and then evaporation backflow 5h, uses I after being separated the series of processes such as drying 2/ CHCl 3in iodine as the Fe in oxidizing complex hydroxide 2+, make it change Fe into 3+, obtain Co-Fe LDH, its reaction process and last handling process all strictly must keep anaerobic.The method, due to experiment condition harshness, is difficult to repeat in the lab.
Homogeneous co-precipitation process is by two metal ion species salts solution mixing under general state, add two or more the positively charged ion coprecipitation that precipitation agent makes to contain in solution again to get off, generate precipitation mixture or sosoloid presoma, refilter, wash and thermolysis, obtain the method for composite oxides.Its shortcoming is, the impact of air (referring generally to oxygen) makes the product obtained have multiple valence state as Fe 2+and Fe 3+, and the effect of precipitation agent is uneven, makes the product synthesized also can heterogeneity.Visible, use the difficult point of Co deposited synthesis transition metal base LDH to be to be difficult to the valence state of the metallic cation controlled in building-up process.
Summary of the invention
Technical problem to be solved by this invention is to overcome the loaded down with trivial details and not high defect of product crystallinity of preparation technology's synthetic method of Co-Fe LDH in prior art, provides the preparation method of a kind of simple to operate, Co-Fe LDH that crystallinity is high.
Contriver is found by large quantity research, in the preparation process of Co-Fe LDH, must pass through FeCl 2hydrate directly generates Fe (OH) 2, and be oxidized to Fe 3+after be then difficult to prepare target product, this with regard to need ensure reaction carry out in the environment of strict anaerobic, but " strict oxygen-free environment " is difficult to reach and controls well; Ensure absolute anaerobic when reacting, simple method is difficult to coordinate harsh reaction conditions, and the present inventor furthers investigate through great many of experiments, solves the problems of the technologies described above eventually through following technical proposals.
The invention provides the preparation method of a kind of Co-Fe LDH, it comprises the steps:
(1) by CoCl 2hydrate, FeCl 2hydrate and water are uniformly mixed, and obtain mixed solution;
(2) under stirring, air-proof condition, in reactor, add the mixed solution described in step (1) and ealkaline buffer successively, obtain reaction solution, be warming up to 100 DEG C ~ 120 DEG C, reaction 3h-5h, reaction system contacts with air, be cooled to 20 DEG C ~ 30 DEG C;
CoCl in described reaction solution 2the volumetric molar concentration of hydrate is 0.0067mol/L-0.0333mol/L, the FeCl in described reaction solution 2the volumetric molar concentration of hydrate is 0.0033mol/L-0.0167mol/L; CoCl described in described reaction solution 2hydrate and FeCl 2the ratio of the volumetric molar concentration of hydrate is (10:1)-(2:5).
In step (1), preferably, described water is the deionized water after deoxidation.
In step (1) and step (2), preferably, described CoCl 2hydrate, FeCl 2hydrate, reductive agent and ealkaline buffer add in form of an aqueous solutions.The preparation process of the aqueous solution of each material is: by CoCl 2hydrate or FeCl 2hydrate or reductive agent or ealkaline buffer are dissolved in the deionized water after deoxidation.
Wherein, preferably, this preparation process is carried out in water bath with thermostatic control, and Keep agitation; The time of described Keep agitation is preferably 5min-20min, and that better is 10min.The temperature of described dissolving is preferably 0 DEG C-30 DEG C, and better is 10 DEG C-20 DEG C.
Wherein, the deionized water after described deoxidation can be obtained by this area ordinary method, preferably comprises the steps: deionized water to boil, and maintains boiling 5min, and sealing, is cooled to 20 DEG C ~ 30 DEG C.
In step (1), described CoCl 2the hydrauture of hydrate can be CoCl 2there is the acceptable arbitrary value of hydrate, is preferably CoCl 26H 2o; Described FeCl 2the hydrauture of hydrate can be FeCl 2there is the acceptable arbitrary value of hydrate, is preferably FeCl 24H 2o.
In the present invention, the CoCl described in described reaction solution 2hydrate and FeCl 2the ratio of the volumetric molar concentration of hydrate is preferably (5:1)-(2:1), and that better is 2:1.
In the present invention, the CoCl in described reaction solution 2the volumetric molar concentration of hydrate is preferably 0.01mol/L-0.0267mol/L.FeCl in described reaction solution 2the volumetric molar concentration of hydrate is preferably 0.0067mol/L-0.0133mol/L.
In step (2), preferably, before adding described mixed solution, also in reactor, reductive agent is added.Described reductive agent refers to and can make Fe 2+not oxidation by air and be progressively oxidized to Fe after the completion of reaction 3+material.Described reductive agent preferably adds in form of an aqueous solutions.The same CoCl of preparation process of the aqueous solution of described reductive agent 2the preparation method of the aqueous solution of hydrate, is: be dissolved in by reductive agent in the deionized water after deoxidation.Described reductive agent is preferably xitix or oxammonium hydrochloride, and better is oxammonium hydrochloride.The timed interval that described reductive agent, mixed solution and ealkaline buffer add successively is preferably 10min.
Wherein, when described reductive agent is xitix, the volumetric molar concentration of the reductive agent in described reaction solution is preferably 0.0033mol/L-0.0267mol/L.When described reductive agent is xitix, the pH of the aqueous solution of described reductive agent is preferably 3 ~ 5.
Wherein, when described reductive agent is oxammonium hydrochloride, the volumetric molar concentration of the reductive agent in described reaction solution is preferably≤0.05mol/L, but non-vanishing.When described reductive agent is oxammonium hydrochloride, oxammonium hydrochloride and FeCl in described reaction solution 2the ratio of the amount of substance of hydrate is preferably (1:1)-(5:1), and that better is (1:1)-(3:1).
In step (2), described ealkaline buffer refers to and the pH of reaction solution can be maintained alkalescence, does not destroy the material of reactant, is preferably Tri(Hydroxymethyl) Amino Methane Hydrochloride or hexamethylenetetramine, and better is hexamethylenetetramine.The volumetric molar concentration of described reaction solution neutral and alkali buffer reagent is preferably 0.0833mol/L ~ 0.3333mol/L, and that better is 0.3mol/L.When described ealkaline buffer is Tri(Hydroxymethyl) Amino Methane Hydrochloride, the pH value of the aqueous solution of described ealkaline buffer is preferably 7.0 ~ 9.5.
In step (2), described stirring is this area routine operation, preferably at room temperature stirs, and described room temperature refers to 20 DEG C ~ 30 DEG C.
In step (2), described reactor is that this area is conventional, and be preferably three-necked flask, autoclave or sealed tube, better is sealed tube.Described reaction is preferably carried out in oil bath.
In step (2), the time of described reaction is preferably 4h; The temperature of described reaction is preferably 110 DEG C.The object of reacting 3h-5h in the reactor of sealing makes CoCl 2hydrate, FeCl 2hydrate generates Co (OH) respectively 2with Fe (OH) 2.
In step (2), the object that described reaction system contacts with air is the Fe made in reaction solution 2+fe is become by the dioxygen oxidation in air 3+.
In step (2), after described cooling, preferably also carry out post-processing operation, described post-processing operation preferably comprises washing, is separated and drying.Described washing is that this area is conventional, is preferably EtOH Sonicate washing and/or ultrapure water supersound washing.Described is separated into this area routine, preferably for whizzer is separated.Described drying is that this area is conventional, is preferably vacuum-drying 5h at 60 DEG C.
In the present invention, in the Co-Fe LDH obtained according to above-mentioned preparation method, Co is Co 2+ion, Fe is Fe 3+ion.
On the basis meeting this area general knowledge, above-mentioned each optimum condition, can arbitrary combination, obtains the preferred embodiments of the invention.
Agents useful for same of the present invention and raw material are all commercially.
Positive progressive effect of the present invention is: the preparation method of Co-Fe LDH provided by the invention is simple to operate, crystallinity is high; In preparation process, the introducing of preferred reductive agent, greatly reduces the difficulty of experiment, improves the productive rate of product.
Accompanying drawing explanation
Fig. 1 is the stereoscan photograph of the Co-Fe LDH that embodiment 1 obtains.
Fig. 2 is the XRD diffractogram of the Co-Fe LDH that embodiment 1 obtains.
Fig. 3 is the stereoscan photograph of the Co-Fe LDH that embodiment 2 obtains.
Fig. 4 is the XRD diffractogram of the Co-Fe LDH that embodiment 2 obtains.
Fig. 5 is the stereoscan photograph of the Co-Fe LDH that embodiment 3 obtains.
Fig. 6 is the XRD diffractogram of the Co-Fe LDH that embodiment 3 obtains.
Fig. 7 is the stereoscan photograph of the Co-Fe LDH that embodiment 4 obtains.
Fig. 8 is the XRD diffractogram of the Co-Fe LDH that embodiment 4 obtains.
Fig. 9 is the stereoscan photograph of the Co-Fe LDH that embodiment 5 obtains.
Figure 10 is the XRD diffractogram of the Co-Fe LDH that embodiment 5 obtains.
Figure 11 is the stereoscan photograph of the Co-Fe LDH that embodiment 6 obtains.
Figure 12 is the XRD diffractogram of the Co-Fe LDH that embodiment 6 obtains.
Figure 13 is the stereoscan photograph of the Co-Fe LDH that embodiment 7 obtains.
Figure 14 is the XRD diffractogram of the Co-Fe LDH that embodiment 7 obtains.
Figure 15 is the stereoscan photograph of the Co-Fe LDH that comparative example 1 obtains.
Figure 16 is the XRD diffractogram of the Co-Fe LDH that comparative example 1 obtains.
Figure 17 is the stereoscan photograph of the Co-Fe LDH that embodiment 8 obtains.
Figure 18 is the XRD diffractogram of the Co-Fe LDH that embodiment 8 obtains.
Figure 19 is the stereoscan photograph of the Co-Fe LDH that embodiment 9 obtains.
Figure 20 is the XRD diffractogram of the Co-Fe LDH that embodiment 9 obtains.
Embodiment
Mode below by embodiment further illustrates the present invention, but does not therefore limit the present invention among described scope of embodiments.The experimental technique of unreceipted actual conditions in the following example, conventionally and condition, or selects according to catalogue.
Document J.AM.CHEM.SOC.2011,133, P613-620:Topochemical Synthesisof Co-Fe Layered DoubleHydroxides at Varied Fe/Co Ratios:UniqueIntercalation of Triiodide and Its Profound Effect gives the XRD figure of Co-Fe LDH, can learn from the document, the peak position that goes out of Co-Fe LDH is mainly 10 °, 20 °, about 30 ° places at 2 θ angles, if peak appears in this three place, then show to obtain this material; Larger in the relative intensity of the diffraction peak at this three place, illustrate that crystallinity is better, wherein based on the diffraction peak of 20 °.
In following embodiment: carry out powder x-ray diffraction to the Co-Fe LDH obtained, source of radiation is Cu-K α, and limit of error is ± 0.2 °.
X-ray powder diffraction detecting instrument: the XRD-6000 type X-ray diffractometer of Japanese Shimadzu Corporation (Shimadzu);
Test condition: with the continuous sweep from 3 ° to 45 ° of 0.02 ° of step-length, sweep velocity 8.0 °/min, pipe pressure 40KV, pipe stream 40mA;
Detect foundation: Chinese Pharmacopoeia 2010 editions 2 annex IX F;
Sense environmental conditions: room temperature.
In following embodiment: scanning electronic microscope detection is carried out to the Co-Fe LDH obtained.The scanning electronic microscope adopted is the S-4800 type scanning electronic microscope that HIT (Hitachi) produces.
Embodiment 1
In the present embodiment, CoCl in described reaction solution 26H 2the volumetric molar concentration of O is 0.01mol/L; FeCl in described reaction solution 24H 2the volumetric molar concentration of O is 0.005mol/L; CoCl 26H 2o and FeCl 24H 2the ratio of the volumetric molar concentration of O is 2:1.
In the present embodiment, described reductive agent is xitix, and the volumetric molar concentration of the reductive agent in described reaction solution is 0.0075mol/L.Described ealkaline buffer is hexamethylenetetramine, and the volumetric molar concentration of described reaction solution neutral and alkali buffer reagent is 0.09mol/L.
The preparation process of the Co-Fe LDH of the present embodiment is as follows:
(1) boil deionized water and maintain azeotropic 5min, be cooled to room temperature for subsequent use; CoCl is taken with electronic balance 26H 2o is 0.7138g, FeCl 24H 2o is 0.2982g, xitix is 0.3963g, hexamethylenetetramine 3.7851g.
(2) CoCl will claimed 26H 2o, FeCl 24H 2o is at room temperature dissolved in 100mL water for subsequent use respectively, obtains mixed solution; Under similarity condition, xitix, hexamethylenetetramine are dissolved in the water for subsequent use of 50mL.
(3) xitix, mixed solution, hexamethylenetetramine are mixed successively in three-necked flask, each step is all that the latter slowly joins in the former, and finally in the oil bath of 110 DEG C, react 4h, reaction system contacts with air, be cooled to 20 DEG C ~ 30 DEG C; Deionized water wash, centrifugal, vacuum-drying.
Sem test and XRD test are carried out to the Co-Fe LDH sample obtained.The result of scanning electron microscope as shown in Figure 1.Result shows: the lamella diameter of Co-Fe LDH is about 2.0um, and burrs on edges does not have well-regulated shape.
XRD test result is as shown in table 1 and Fig. 2.XRD figure also show at 2 θ angles be 10 ° and 20 ° time characteristic peak not obvious, the characteristic peak of about 30 ° is more weak, and has occurred assorted peak at about 36 °.
Visible, although the Co-Fe LDH lamella that the present embodiment obtains is not too regular, crystallinity is slightly poor, really obtains Co-Fe LDH by simple processing step and condition, and obtained its lamella.
The XRD diffraction peak of the Co-Fe LDH of table 1 embodiment 1
Numbering 2 θ angles (°) Relative intensity Numbering 2 θ angles (°) Relative intensity
1 5.60 24 18 39.36 10
2 7.94 24 19 41.00 10
3 9.06 20 20 43.56 14
4 11.14 24 21 45.56 10
5 13.12 18 22 47.20 10
6 15.70 14 23 49.12 8
7 17.62 14 24 51.90 12
8 19.80 18 25 53.28 6
9 21.74 16 26 55.78 12
10 23.46 12 27 57.76 16
11 25.52 14 28 59.16 14
12 27.64 14 29 61.16 12
13 29.02 14 30 63.84 12
14 31.18 20 31 65.20 18
15 33.22 12 32 67.34 10
16 35.26 14 33 69.38 8
17 37.04 16 34
Embodiment 2
In the present embodiment, CoCl in described reaction solution 26H 2the volumetric molar concentration of O is 0.01mol/L; FeCl in described reaction solution 24H 2the volumetric molar concentration of O is 0.005mol/L; CoCl 26H 2o and FeCl 24H 2the ratio of the volumetric molar concentration of O is 2:1.
In the present embodiment, described reductive agent is xitix, and the volumetric molar concentration of the reductive agent in described reaction solution is 0.0075mol/L.Described ealkaline buffer is hexamethylenetetramine, and the volumetric molar concentration of described reaction solution neutral and alkali buffer reagent is 0.09mol/L.
The preparation process of the Co-Fe LDH of the present embodiment is as follows:
(1) boil deionized water and maintain azeotropic 5min, be cooled to room temperature for subsequent use; With the accurate weighing CoCl of electronic balance 26H 2o is 0.7142g, FeCl 24H 2o is 0.2958g, xitix is 0.3987g, hexamethylenetetramine 3.7887g.
(2) CoCl will claimed 26H 2o, FeCl 24H 2o, xitix, hexamethylenetetramine join in the autoclave filling 300mL water for subsequent use successively.
(3) temperature risen to 110 DEG C and maintain reaction 4h, reaction system contacts with air, is cooled to 20 DEG C ~ 30 DEG C; Deionized water wash, centrifugal, vacuum-drying.
Sem test and XRD test are carried out to the Co-Fe LDH sample obtained.The result of scanning electron microscope as shown in Figure 3.SEM picture shows: the lamella diameter of Co-Fe LDH is at about 2.0um, and fragment is more, irregular shape.
XRD test result is as shown in table 2 and Fig. 4.It is that the characteristic peak of 10 °, 20 °, about 30 ° is not obvious that XRD figure sheet is presented at 2 θ angles, and occurs very strong assorted peak at 18 °, about 36 °.
Visible, although the Co-Fe LDH lamella that the present embodiment obtains is not too regular, crystallinity is poor, effect is slightly poorer than embodiment 1, has really obtained Co-Fe LDH by simple processing step and condition, and has obtained its lamella.
The XRD diffraction peak of the Co-Fe LDH of table 2 embodiment 2
Numbering 2 θ angles (°) Relative intensity Numbering 2 θ angles (°) Relative intensity
1 5.52 24 18 39.12 10
2 7.76 20 19 41.80 6
3 9.54 18 20 43.40 12
4 11.22 20 21 45.44 8
5 13.64 16 22 47.16 8
6 15.34 18 23 49.14 8
7 17.38 14 24 51.42 14
8 19.30 24 25 53.84 8
9 21.30 14 26 55.78 12
10 23.78 12 27 57.40 10
11 25.88 10 28 59.14 14
12 27.54 10 29 61.78 12
13 29.76 12 30 63.26 16
14 31.94 10 31 65.00 10
15 33.72 10 32 67.62 8
16 35.66 24 33 69.80 10
17 37.88 20 34
Embodiment 3
In the present embodiment, CoCl in described reaction solution 26H 2the volumetric molar concentration of O is 0.01mol/L; FeCl in described reaction solution 24H 2the volumetric molar concentration of O is 0.005mol/L; CoCl 26H 2o and FeCl 24H 2the ratio of the volumetric molar concentration of O is 2:1.
In the present embodiment, described reductive agent is xitix, and the volumetric molar concentration of the reductive agent in described reaction solution is 0.0075mol/L.Described ealkaline buffer is hexamethylenetetramine, and the volumetric molar concentration of described reaction solution neutral and alkali buffer reagent is 0.09mol/L.
The preparation process of the Co-Fe LDH of the present embodiment is as follows:
(1) boil deionized water and maintain azeotropic 5min, be cooled to room temperature for subsequent use; With the accurate weighing CoCl of electronic balance 26H 2o is 0.7148g, FeCl 24H 2o is 0.2970g, xitix is 0.3973g, hexamethylenetetramine 3.7866g.
(2) CoCl will claimed 26H 2o, FeCl 24H 2o controls at room temperature to be dissolved in respectively in 100mL water for subsequent use, obtains mixed solution; Under similarity condition, xitix, hexamethylenetetramine are dissolved in the water for subsequent use of 50mL.
(3) xitix, mixed solution, hexamethylenetetramine are mixed in sealed tube successively, each step is all that the latter slowly joins in the former, and finally in the oil bath of 110 DEG C, react 4h, reaction system contacts with air, is cooled to 20 DEG C ~ 30 DEG C; Deionized water wash, centrifugal, vacuum-drying.
Sem test and XRD test are carried out to the Co-Fe LDH sample obtained.The result of scanning electron microscope as shown in Figure 5.SEM figure shows: the lamella diameter of Co-Fe LDH is at about 1.6um, and edge shows slightly the shape revealing rule.
XRD test result is as shown in table 3 and Fig. 6.It is that the characteristic peak of about 10 ° is obvious that XRD figure also show at 2 θ angles, and the characteristic peak of 20 °, about 30 ° is more weak, and has occurred assorted peak at about 36 °.
Visible, the Co-Fe LDH that the present embodiment obtains is better than embodiment 1 and embodiment 2, and lamella shows slightly the shape revealing rule, and crystallinity is good.
The XRD diffraction peak of the Co-Fe LDH of table 3 embodiment 3
Numbering 2 θ angles (°) Relative intensity Numbering 2 θ angles (°) Relative intensity
1 5.56 26 18 39.16 16
2 7.12 22 19 41.08 8
3 9.34 20 20 43.54 8
4 11.38 20 21 45.52 6
5 13.44 18 22 47.60 8
6 15.74 16 23 49.80 8
7 17.78 16 24 51.74 10
8 19.86 16 25 53.66 8
9 21.58 16 26 55.70 10
10 23.18 14 27 57.68 8
11 25.58 12 28 89.72 10
12 27.62 10 29 61.92 12
13 29.48 12 30 63.46 12
14 31.60 12 31 65.26 14
15 33.86 18 32 67.22 12
16 35.50 18 33 69.40 10
17 37.56 14 34
Embodiment 4
In the present embodiment, CoCl in described reaction solution 26H 2the volumetric molar concentration of O is 0.01mol/L; FeCl in described reaction solution 24H 2the volumetric molar concentration of O is 0.005mol/L; CoCl 26H 2o and FeCl 24H 2the ratio of the volumetric molar concentration of O is 2:1.
In the present embodiment, described reductive agent is oxammonium hydrochloride, and the volumetric molar concentration of the reductive agent in described reaction solution is 0.005mol/L.Oxammonium hydrochloride and FeCl in described reaction solution 24H 2the ratio of the amount of substance of O is 1:1.Described ealkaline buffer is hexamethylenetetramine, and the volumetric molar concentration of described reaction solution neutral and alkali buffer reagent is 0.09mol/L.
The preparation process of the Co-Fe LDH of the present embodiment is as follows:
(1) boil deionized water and maintain azeotropic 5min, be cooled to room temperature for subsequent use; CoCl is taken with electronic balance 26H 2o is 0.7154g, FeCl 24H 2o is 0.2990g, oxammonium hydrochloride is 0.1042g, hexamethylenetetramine 3.7855g.
(2) CoCl will claimed 26H 2o, FeCl 24H 2o controls at room temperature to be dissolved in respectively in 100mL water for subsequent use, obtains mixed solution; Under similarity condition, oxammonium hydrochloride, hexamethylenetetramine are dissolved in the water for subsequent use of 50mL.
(3) oxammonium hydrochloride, mixed solution, hexamethylenetetramine are mixed in sealed tube successively, each step is all that the latter slowly joins in the former, and finally in the oil bath of 110 DEG C, react 4h, reaction system contacts with air, is cooled to 20 DEG C ~ 30 DEG C; Deionized water wash, centrifugal, vacuum-drying.
Sem test and XRD test are carried out to the Co-Fe LDH sample obtained.The result of scanning electron microscope as shown in Figure 7.SEM figure shows: do not have apparent lamella in Co-Fe LDH sample.
XRD test result is as shown in table 4 and Fig. 8.XRD figure also show and is 10 °, 20 °, about 30 ° at 2 θ angles and occurred characteristic peak, but assorted peak has also appearred in all the other many places.
Visible, although the lamella effect that the present embodiment obtains Co-Fe LDH is not so good, really obtained Co-Fe LDH, and its diffraction peak situation is better than embodiment 1.
The XRD diffraction peak of the Co-Fe LDH of table 4 embodiment 4
Numbering 2 θ angles (°) Relative intensity Numbering 2 θ angles (°) Relative intensity
1 5.52 56 18 39.92 30
2 7.80 46 19 41.82 24
3 9.22 42 20 43.4 24
4 11.84 40 21 45.04 28
5 13.28 38 22 47.86 22
6 15.42 38 23 49.62 28
7 17.06 38 24 51.68 20
8 19.30 28 25 53.74 34
9 21.76 28 26 55.52 34
10 23.16 30 27 57.70 34
11 25.34 30 28 59.42 28
12 27.76 38 29 61.44 28
13 29.32 48 30 63.14 28
14 31.02 34 31 65.34 28
15 33.66 30 32 67.52 30
16 35.16 30 33 69.68 24
17 37.86 26 34
Embodiment 5
In the present embodiment, CoCl in described reaction solution 26H 2the volumetric molar concentration of O is 0.012mol/L; FeCl in described reaction solution 24H 2the volumetric molar concentration of O is 0.006mol/L; CoCl 26H 2o and FeCl 24H 2the ratio of the volumetric molar concentration of O is 2:1.
In the present embodiment, do not add reductive agent.Described ealkaline buffer is hexamethylenetetramine, and the volumetric molar concentration of described reaction solution neutral and alkali buffer reagent is 0.108mol/L.
The preparation process of the Co-Fe LDH of the present embodiment is as follows:
(1) boil deionized water and maintain azeotropic 5min, be cooled to room temperature for subsequent use; CoCl is taken with electronic balance 26H 2o is 0.7150g, FeCl 24H 2o is 0.2966g, hexamethylenetetramine 3.7855g.
(2) CoCl will claimed 26H 2o, FeCl 24H 2o controls at room temperature to be dissolved in respectively in 100mL water for subsequent use, obtains mixed solution; Under similarity condition, hexamethylenetetramine is dissolved in the water for subsequent use of 50mL.
(3) mixed solution, hexamethylenetetramine are mixed in sealed tube successively, the latter slowly joins in the former, and finally in the oil bath of 110 DEG C, react 4h, reaction system contacts with air, is cooled to 20 DEG C ~ 30 DEG C; Deionized water wash, centrifugal, vacuum-drying.
Sem test and XRD test are carried out to the Co-Fe LDH sample obtained.The result of scanning electron microscope as shown in Figure 9.SEM figure shows: Co-Fe LDH sample strip Rotating fields difference is clear.
XRD test result is as shown in table 5 and Figure 10.It is that the characteristic peak of 10 °, 20 °, about 30 ° is not obvious that XRD figure also show at 2 θ angles, and very strong assorted peak appears in all the other many places.
Visible, embodiment 5 is not when adding reductive agent, although obtained product lamella is poor, really obtained Co-Fe LDH, its effect is slightly worse than embodiment 3.
The XRD diffraction peak of the Co-Fe LDH of table 5 embodiment 5
Numbering 2 θ angles (°) Relative intensity Numbering 2 θ angles (°) Relative intensity
1 5.02 196 18 39.02 38
2 7.20 36 19 41.14 22
3 9.88 34 20 43.30 28
4 11.88 34 21 45.20 26
5 13.62 38 22 47.64 26
6 15.68 30 23 49.64 20
7 17.62 36 24 51.32 32
8 19.20 26 25 53.98 28
9 21.94 28 26 55.42 34
10 23.54 26 27 57.20 26
11 25.28 26 28 59.58 26
12 27.86 62 29 61.16 28
13 29.42 42 30 63.78 28
14 31.90 34 31 65.98 28
15 33.68 36 32 67.08 28
16 35.02 28 33 69.50 28
17 37.42 30 34
Embodiment 6
In the present embodiment, CoCl in described reaction solution 26H 2the volumetric molar concentration of O is 0.01mol/L; FeCl in described reaction solution 24H 2the volumetric molar concentration of O is 0.005mol/L; CoCl 26H 2o and FeCl 24H 2the ratio of the volumetric molar concentration of O is 2:1.
In the present embodiment, described reductive agent is oxammonium hydrochloride, and the volumetric molar concentration of the reductive agent in described reaction solution is 0.015mol/L.Oxammonium hydrochloride and FeCl in described reaction solution 24H 2the ratio of the amount of substance of O is 3:1.Described ealkaline buffer is hexamethylenetetramine, and the volumetric molar concentration of described reaction solution neutral and alkali buffer reagent is 0.09mol/L.
The preparation process of the Co-Fe LDH of the present embodiment is as follows:
(1) boil deionized water and maintain azeotropic 5min, be cooled to room temperature for subsequent use; CoCl is taken with electronic balance 26HO is 0.7138g, FeCl 24H 2o is 0.2958g, oxammonium hydrochloride is 0.3128g, hexamethylenetetramine 3.7858g.
(2) CoCl will claimed 26H 2o, FeCl 24H 2o controls at room temperature to be dissolved in respectively in 100mL water for subsequent use, obtains mixed solution; Under similarity condition, oxammonium hydrochloride, hexamethylenetetramine are dissolved in the water for subsequent use of 50mL.
(3) oxammonium hydrochloride, mixed solution, hexamethylenetetramine are mixed in sealed tube successively, each step is all that the latter slowly joins in the former, and finally in the oil bath of 110 DEG C, react 4h, reaction system contacts with air, is cooled to 20 DEG C ~ 30 DEG C; Deionized water wash, centrifugal, vacuum-drying.
Sem test and XRD test are carried out to the Co-Fe LDH sample obtained.The result of scanning electron microscope as shown in figure 11.SEM figure shows: the lamella diameter of Co-Fe LDH at about 1.0um, edge hexagonal configuration clearly as seen.Meanwhile, by SEM picture also can find out more intuitively unit surface, regular shape, the number of the lamella of good crystallinity, this index can reflect the productive rate of product indirectly, visible, and the productive rate of the Co-Fe LDH of the present embodiment is very high.
XRD test result is as shown in table 6 and Figure 12.It is that the characteristic peak of 10 °, 20 °, about 30 ° is obviously and very strong that XRD figure also show at 2 θ angles, and crystallinity is fine.
Visible, laminated structure and the crystallinity of embodiment 6 are all better than embodiment 1-5.
The XRD diffraction peak of the Co-Fe LDH of table 6 embodiment 6
Numbering 2 θ angles (°) Relative intensity Numbering 2 θ angles (°) Relative intensity
1 5.14 807 18 39.00 267
2 7.40 633 19 41.08 220
3 9.12 473 20 43.08 273
4 11.20 3127 21 45.52 427
5 13.90 300 22 47.38 180
6 15.26 240 23 49.46 153
7 17.62 207 24 51.02 200
8 19.58 207 25 53.86 173
9 21.94 340 26 55.32 173
10 23.42 400 27 57.38 187
11 25.38 180 28 59.02 567
12 27.04 187 29 61.80 240
13 29.98 227 30 63.02 287
14 31.78 173 31 65.06 147
15 33.88 1400 32 67.58 100
16 35.54 580 33 69.76 213
17 37.98 560 34
Embodiment 7
In the present embodiment, CoCl in described reaction solution 26H 2the volumetric molar concentration of O is 0.01mol/L; FeCl in described reaction solution 24H 2the volumetric molar concentration of O is 0.005mol/L; CoCl 26H 2o and FeCl 24H 2the ratio of the volumetric molar concentration of O is 2:1.
In the present embodiment, described reductive agent is oxammonium hydrochloride, and the volumetric molar concentration of the reductive agent in described reaction solution is 0.025mol/L.Oxammonium hydrochloride and FeCl in described reaction solution 24H 2the ratio of the amount of substance of O is 5:1.Described ealkaline buffer is hexamethylenetetramine, and the volumetric molar concentration of described reaction solution neutral and alkali buffer reagent is 0.09mol/L.
The preparation process of the Co-Fe LDH of the present embodiment is as follows:
(1) boil deionized water and maintain azeotropic 5min, be cooled to room temperature for subsequent use; CoCl is taken with electronic balance 26H 2o is 0.7154g, FeCl 24H 2o is 0.2936g, oxammonium hydrochloride is 0.5210g, hexamethylenetetramine 3.7869g.
(2) CoCl will claimed 26H 2o, FeCl 24H 2o controls at room temperature to be dissolved in respectively in 100mL water for subsequent use, obtains mixed solution; Under similarity condition, oxammonium hydrochloride, hexamethylenetetramine are dissolved in the water for subsequent use of 50mL.
(3) oxammonium hydrochloride, mixed solution, hexamethylenetetramine are mixed in sealed tube successively, each step is all that the latter slowly joins in the former, and finally in the oil bath of 110 DEG C, react 4h, reaction system contacts with air, is cooled to 20 DEG C ~ 30 DEG C; Deionized water wash, centrifugal, vacuum-drying.
Sem test and XRD test are carried out to the Co-Fe LDH sample obtained.The result of scanning electron microscope as shown in figure 13.SEM figure shows: the lamella of Co-Fe LDH sample is not obvious, and diameter is about 0.4um, and edge shape is not too obvious.
XRD test result is as shown in table 7 and Figure 14.It is that the characteristic peak of 10 °, 20 °, about 30 ° is not too obvious that XRD figure also show at 2 θ angles, and assorted peak appears in all the other many places.
Visible, embodiment 7 changes the concentration of reductive agent, the crystallinity of obtained Co-Fe LDH and laminated structure slightly poorer than the effect of embodiment 6.
The XRD diffraction peak of the Co-Fe LDH of table 7 embodiment 7
Numbering 2 θ angles (°) Relative intensity Numbering 2 θ angles (°) Relative intensity
1 5.52 56 18 39.92 30
2 7.80 46 19 41.08 22
3 9.22 42 20 43.40 24
4 11.74 36 21 45.84 28
5 13.86 34 22 47.74 32
6 15.42 38 23 49.62 28
7 17.06 38 24 51.26 28
8 19.96 32 25 53.74 34
9 21.90 32 26 55.00 28
10 23.08 34 27 57.22 30
11 25.92 34 28 59.10 32
12 27.90 36 29 61.68 26
13 29.54 52 30 63.96 28
14 31.02 34 31 65.34 28
15 33.52 28 32 67.72 28
16 35.16 30 33 69.12 26
17 37.22 36 34
Comparative example 1
In this comparative example, CoCl in described reaction solution 26H 2the volumetric molar concentration of O is 0.01mol/L; FeCl in described reaction solution 24H 2the volumetric molar concentration of O is 0.005mol/L; CoCl 26H 2o and FeCl 24H 2the ratio of the volumetric molar concentration of O is 2:1.
In this comparative example, described reductive agent is oxammonium hydrochloride, and the volumetric molar concentration of the reductive agent in described reaction solution is 0.075mol/L.Oxammonium hydrochloride and FeCl in described reaction solution 24H 2the ratio of the amount of substance of O is 15:1.Described ealkaline buffer is hexamethylenetetramine, and the volumetric molar concentration of described reaction solution neutral and alkali buffer reagent is 0.09mol/L.
The preparation process of the Co-Fe LDH of this comparative example is as follows:
(1) boil deionized water and maintain azeotropic 5min, be cooled to room temperature for subsequent use; CoCl is taken with electronic balance 26H 2o is 0.7166g, FeCl 24H 2o is 0.2950g, oxammonium hydrochloride is 1.563g, hexamethylenetetramine 3.7874g.
(2) CoCl will claimed 26H 2o, FeCl 24H 2o controls at room temperature to be dissolved in respectively in 100mL water for subsequent use, obtains mixed solution; Under similarity condition, oxammonium hydrochloride, hexamethylenetetramine are dissolved in the water for subsequent use of 50mL.
(3) oxammonium hydrochloride, mixed solution, hexamethylenetetramine are mixed in sealed tube successively, each step is all that the latter slowly joins in the former, and finally in the oil bath of 110 DEG C, react 4h, reaction system contacts with air, is cooled to 20 DEG C ~ 30 DEG C; Deionized water wash, centrifugal, vacuum-drying.
Sem test and XRD test are carried out to the Co-Fe LDH sample obtained.The result of scanning electron microscope as shown in figure 15.SEM figure shows: the lamella diameter of Co-Fe LDH sample is large, and be about about 2.5um, laminated structure is undesirable.
XRD test result is as shown in table 8 and Figure 16.It is that the characteristic peak of about 10 ° is obvious that XRD figure also show at 2 θ angles, and the characteristic peak intensity of about 20 ° is less, and has occurred very strong assorted peak, and crystallinity is very poor.
Visible, as oxammonium hydrochloride in reaction solution and FeCl 24H 2when the ratio of the amount of substance of O reaches 15:1, technique effect of the present invention cannot be realized.
The XRD diffraction peak of the Co-Fe LDH of table 8 comparative example 1
Numbering 2 θ angles (°) Relative intensity Numbering 2 θ angles (°) Relative intensity
1 5.04 713 18 39.02 247
2 7.06 500 19 41.80 167
3 9.06 413 20 43.20 213
4 11.52 760 21 45.00 193
5 13.04 260 22 47.42 113
6 15.92 213 23 49.46 127
7 17.64 153 24 51.26 153
8 19.16 307 25 53.62 133
9 21.80 153 26 55.88 153
10 23.16 333 27 57.82 160
11 25.38 127 28 59.32 373
12 27.44 167 29 61.00 200
13 29.88 153 30 63.06 153
14 31.20 207 31 65.14 207
15 33.98 413 32 67.72 93
16 35.14 413 33 69.56 107
17 37.30 373 34
Embodiment 8
In the present embodiment, CoCl in described reaction solution 26H 2the volumetric molar concentration of O is 0.01mol/L; FeCl in described reaction solution 24H 2the volumetric molar concentration of O is 0.005mol/L; CoCl 26H 2o and FeCl 24H 2the ratio of the volumetric molar concentration of O is 2:1.
In the present embodiment, described reductive agent is oxammonium hydrochloride, and the volumetric molar concentration of the reductive agent in described reaction solution is 0.015mol/L.Oxammonium hydrochloride and CoCl in described reaction solution 26H 2the ratio of the amount of substance of O is 3:1.Described ealkaline buffer is Tri(Hydroxymethyl) Amino Methane Hydrochloride, and the volumetric molar concentration of described reaction solution neutral and alkali buffer reagent is 0.09mol/L.
The preparation process of the Co-Fe LDH of the present embodiment is as follows:
(1) boil deionized water and maintain azeotropic 5min, be cooled to room temperature for subsequent use; CoCl is taken with electronic balance 26HO is 0.7139g, FeCl 24H 2o is 0.2956g, oxammonium hydrochloride is 0.3130g, Tri(Hydroxymethyl) Amino Methane Hydrochloride 4.2552g.
(2) CoCl will claimed 26H 2o, FeCl 24H 2o controls at room temperature to be dissolved in respectively in 100mL water for subsequent use, obtains mixed solution; Under similarity condition, oxammonium hydrochloride, Tri(Hydroxymethyl) Amino Methane Hydrochloride are dissolved in the water for subsequent use of 50mL.
(3) oxammonium hydrochloride, mixed solution, Tri(Hydroxymethyl) Amino Methane Hydrochloride are mixed successively in sealed tube, each step is all that the latter slowly joins in the former, and finally in the oil bath of 110 DEG C, react 4h, reaction system contacts with air, be cooled to 20 DEG C ~ 30 DEG C; Deionized water wash, centrifugal, vacuum-drying.
Sem test and XRD test are carried out to the Co-Fe LDH sample obtained.The result of scanning electron microscope as shown in figure 17.
SEM figure shows: the laminated structure of Co-Fe LDH is poor.
XRD test result is as shown in table 9 and Figure 18.XRD figure also show at 10 °, 2 θ angle, the characteristic peak of 20 °, 30 ° is very weak, and assorted peak is a lot.
Visible, the present embodiment only changes the kind of ealkaline buffer, and all the other conditions are with embodiment 6, and result shows the lamella really having obtained Co-Fe LDH, but its laminated structure and crystallinity are slightly worse than embodiment 6.
The XRD diffraction peak of the Co-Fe LDH of table 9 embodiment 8
Numbering 2 θ angles (°) Relative intensity Numbering 2 θ angles (°) Relative intensity
1 5.64 34 18 39.42 10
2 7.64 24 19 41.76 12
3 9.74 20 20 43.68 10
4 11.44 20 21 45.48 12
5 13.48 20 22 47.24 12
6 15.16 20 23 49.56 10
7 17.14 20 24 51.66 14
8 19.08 22 25 53.36 16
9 21.38 18 26 55.18 12
10 23.58 20 27 57.54 12
11 25.54 16 28 59.22 12
12 27.84 16 29 61.50 12
13 29.98 16 30 63.44 16
14 31.60 14 31 65.42 10
15 33.62 16 32 67.54 14
16 35.48 20 33 69.68 10
17 37.78 12 34
Embodiment 9
In the present embodiment, CoCl in described reaction solution 26H 2the volumetric molar concentration of O is 0.01mol/L; FeCl in described reaction solution 24H 2the volumetric molar concentration of O is 0.005mol/L; CoCl 26H 2o and FeCl 24H 2the ratio of the volumetric molar concentration of O is 2:1.
In the present embodiment, described reductive agent is oxammonium hydrochloride, and the volumetric molar concentration of the reductive agent in described reaction solution is 0.015mol/L.Oxammonium hydrochloride and FeCl in described reaction solution 24H 2the ratio of the amount of substance of O is 3:1.Described ealkaline buffer is Tri(Hydroxymethyl) Amino Methane Hydrochloride, and the volumetric molar concentration of described reaction solution neutral and alkali buffer reagent is 0.18mol/L.
The preparation process of the Co-Fe LDH of the present embodiment is as follows:
(1) boil deionized water and maintain azeotropic 5min, be cooled to room temperature for subsequent use; CoCl is taken with electronic balance 26HO is 0.7137g, FeCl 24H 2o is 0.2954g, oxammonium hydrochloride is 0.3132g, Tri(Hydroxymethyl) Amino Methane Hydrochloride 8.3010g.
(2) CoCl will claimed 26H 2o, FeCl 24H 2o controls at room temperature to be dissolved in respectively in 100mL water for subsequent use, obtains mixed solution; Under similarity condition, oxammonium hydrochloride, Tri(Hydroxymethyl) Amino Methane Hydrochloride are dissolved in the water for subsequent use of 50mL.
(3) oxammonium hydrochloride, mixed solution, Tri(Hydroxymethyl) Amino Methane Hydrochloride are mixed successively in sealed tube, each step is all that the latter slowly joins in the former, and finally in the oil bath of 110 DEG C, react 4h, reaction system contacts with air, be cooled to 20 DEG C ~ 30 DEG C; Deionized water wash, centrifugal, vacuum-drying.
Sem test and XRD test are carried out to the Co-Fe LDH sample obtained.The result of scanning electron microscope as shown in figure 19.
SEM figure shows: the laminated structure of Co-Fe LDH is slightly poor.
XRD test result is as shown in table 10 and Figure 20.XRD figure also show and is 10 °, 20 °, 30 ° at 2 θ angles and occurred characteristic peak, but assorted peak is more.
Compared with embodiment 8, although the present embodiment increases the concentration of ealkaline buffer, the laminated structure of obtained Co-FeLDH and crystallinity are slightly better than embodiment 8, the crystallinity of Co-Fe LDH and lamella are worse than the effect of embodiment 6.
The XRD diffraction peak of the Co-Fe LDH of table 10 embodiment 9
Numbering 2 θ angles (°) Relative intensity Numbering 2 θ angles (°) Relative intensity
1 5.30 28 18 39.22 16
2 7.94 24 19 41.54 14
3 9.20 24 20 43.16 16
4 11.20 42 21 45.80 14
5 13.26 24 22 47.72 12
6 15.00 20 23 49.96 14
7 17.14 24 24 51.82 16
8 19.14 42 25 53.84 12
9 21.56 28 26 55.78 12
10 23.98 30 27 57.44 12
11 25.44 18 28 59.10 18
12 27.12 28 29 61.56 14
13 29.54 22 30 63.30 14
14 31.08 24 31 65.12 14
15 33.68 24 32 67.56 12
16 35.04 18 33 69.02 14
17 37.00 20 34
Embodiment 10
In the present embodiment, CoCl in described reaction solution 26H 2the volumetric molar concentration of O is 0.0067mol/L; FeCl in described reaction solution 24H 2the volumetric molar concentration of O is 0.0167mol/L; CoCl 26H 2o and FeCl 24H 2the ratio of the volumetric molar concentration of O is 2:5; Described reductive agent is oxammonium hydrochloride, and its volumetric molar concentration is 0.05mol/L; Reaction times is 3h, and temperature of reaction is 120 DEG C, and remaining preparation condition and step are with embodiment 6.
Embodiment 11
In the present embodiment, CoCl in described reaction solution 26H 2the volumetric molar concentration of O is 0.0333mol/L; FeCl in described reaction solution 24H 2the volumetric molar concentration of O is 0.0033mol/L; CoCl 26H 2o and FeCl 24H 2the ratio of the volumetric molar concentration of O is 10:1; Reaction times is 5h, and temperature of reaction is 100 DEG C, and remaining preparation condition and step are with embodiment 6.
Effect example 1
Embodiment 1 ~ 3 have studied xitix as the crystallinity of reductive agent to LDH lamella and the provide protection of ferrous ion, and embodiment 4,6,7 have studied hydrochloric acid hydroxyl by as the crystallinity of reductive agent to LDH lamella and the provide protection of ferrous ion.Result shows, compared with embodiment 4,6,7, when xitix is as reductive agent, the corner of lamella does not have good crystallization, has crimp, visible, its effect than oxammonium hydrochloride as slightly poor during reductive agent.Visible, the present invention preferably should add the scheme of reductive agent, and wherein, reductive agent can be oxammonium hydrochloride and xitix, the preferred oxammonium hydrochloride of described reductive agent.
Effect example 2
Embodiment 1 and embodiment 2, under the prerequisite that other reaction conditionss are identical, have studied the impact of oil bath on preparation result, and from Fig. 1 and Fig. 3 relatively, the lamella that oil bath obtains is comparatively even, and therefore, reaction of the present invention is preferably carried out in oil bath.
Effect example 3
The present embodiment have studied the impact of reaction kit on preparation result, and involved reaction kit comprises three-necked flask, autoclave and sealed tube.For the reaction under oil bath, research finds that there is strict separation air and the instrument that can bear certain gaseous tension has very great help to experiment.Therefore, obtain in a large amount of revision tests of embodiment 1,2,3 as drawn a conclusion: preparation method of the present invention needs to carry out under air-proof condition, is preferably sealed tube.
Effect example 4
Embodiment 5,4,6,7 is experiment of single factor of the concentration of oxammonium hydrochloride in reaction solution, wherein, does not add oxammonium hydrochloride in embodiment 5, the FeCl in the oxammonium hydrochloride of embodiment 4 and reaction solution 24H 2the ratio of the amount of substance of O is (1:1), the FeCl in the oxammonium hydrochloride of embodiment 6 and reaction solution 24H 2the ratio of the amount of substance of O is (3:1), the FeCl in the oxammonium hydrochloride of embodiment 7 and reaction solution 24H 2the ratio of the amount of substance of O is (5:1).As can be seen from SEM figure and XRD detected result, the crystallinity of the Co-Fe LDH of embodiment 6 is best, and lamella is best.Visible, oxammonium hydrochloride and FeCl in described reaction solution 24H 2the ratio of the amount of substance of O is preferably (1:1)-(5:1), and that better is (1:1)-(3:1), and that better is (3:1) further.

Claims (17)

1. a preparation method of Co-Fe LDH, is characterized in that, it comprises the steps:
(1) by CoCl 2hydrate, FeCl 2hydrate and water are uniformly mixed, and obtain mixed solution;
(2) in stirring, under air-proof condition, add reductive agent, mixed solution described in step (1) and ealkaline buffer successively in reactor, obtain reaction solution, be warming up to 100 DEG C ~ 120 DEG C, reaction 3h-5h, reaction system contacts with air afterwards, be cooled to 20 DEG C ~ 30 DEG C;
CoCl in described reaction solution 2the volumetric molar concentration of hydrate is 0.0067mol/L-0.0333mol/L, the FeCl in described reaction solution 2the volumetric molar concentration of hydrate is 0.0033mol/L-0.0167mol/L; CoCl described in described reaction solution 2hydrate and FeCl 2the ratio of the volumetric molar concentration of hydrate is (10:1)-(2:5);
Described reductive agent is xitix or oxammonium hydrochloride, and adds in form of an aqueous solutions; When described reductive agent is xitix, the volumetric molar concentration of the reductive agent in described reaction solution is 0.0033mol/L-0.0267mol/L, and the pH of the aqueous solution of described reductive agent is 3 ~ 5; When described reductive agent is oxammonium hydrochloride, the volumetric molar concentration of the reductive agent in described reaction solution is≤0.05mol/L, but non-vanishing; Oxammonium hydrochloride and FeCl in described reaction solution 2the ratio of the amount of substance of hydrate is (1:1)-(5:1).
2. preparation method as claimed in claim 1, it is characterized in that, in step (1), described water is the deionized water after deoxidation; In step (1) and step (2), described CoCl 2hydrate, FeCl 2hydrate and ealkaline buffer add respectively in form of an aqueous solutions; Described CoCl 2hydrate, FeCl 2the preparation process of the aqueous solution of hydrate and ealkaline buffer is: by CoCl 2hydrate or FeCl 2hydrate or ealkaline buffer are dissolved in the deionized water after deoxidation.
3. preparation method as claimed in claim 2, is characterized in that, described CoCl 2hydrate, FeCl 2the preparation process of the aqueous solution of hydrate and ealkaline buffer is carried out in water bath with thermostatic control, and Keep agitation; Described CoCl 2hydrate, FeCl 2in the preparation process of the aqueous solution of hydrate and ealkaline buffer, the temperature of described dissolving is 0 DEG C-30 DEG C; Deionized water after described deoxidation is obtained by following method: boiled by deionized water, and maintains boiling 5min, and sealing, is cooled to 20 DEG C ~ 30 DEG C.
4. preparation method as claimed in claim 3, it is characterized in that, the time of described Keep agitation is 5min-20min; Described CoCl 2hydrate, FeCl 2in the preparation process of the aqueous solution of hydrate and ealkaline buffer, the temperature of described dissolving is 10 DEG C-20 DEG C.
5. preparation method as claimed in claim 4, it is characterized in that, the time of described Keep agitation is 10min.
6. preparation method as claimed in claim 1, is characterized in that, the CoCl in described reaction solution 2the volumetric molar concentration of hydrate is 0.01mol/L-0.0267mol/L; FeCl in described reaction solution 2the volumetric molar concentration of hydrate is 0.0067mol/L-0.0133mol/L; CoCl described in described reaction solution 2hydrate and described FeCl 2the ratio of the volumetric molar concentration of hydrate is (5:1)-(2:1).
7. preparation method as claimed in claim 6, is characterized in that, the CoCl described in described reaction solution 2hydrate and described FeCl 2the ratio of the volumetric molar concentration of hydrate is 2:1.
8. the preparation method as described in any one of claim 1-5, is characterized in that, the preparation process of the aqueous solution of described reductive agent is: be dissolved in by reductive agent in the deionized water after deoxidation.
9. preparation method as claimed in claim 8, it is characterized in that, described reductive agent, mixed solution and the ealkaline buffer timed interval added successively in reactor is 10min.
10. preparation method as claimed in claim 8, is characterized in that, when described reductive agent is oxammonium hydrochloride, and oxammonium hydrochloride and FeCl in described reaction solution 2the ratio of the amount of substance of hydrate is (1:1)-(3:1).
11. preparation methods as claimed in claim 1, is characterized in that, in step (1), and described CoCl 2hydrate is CoCl 26H 2o; Described FeCl 2hydrate is FeCl 24H 2o.
12. preparation methods as claimed in claim 1, is characterized in that, in step (2), described ealkaline buffer is Tri(Hydroxymethyl) Amino Methane Hydrochloride or hexamethylenetetramine; The volumetric molar concentration of described reaction solution neutral and alkali buffer reagent is 0.0833mol/L ~ 0.3333mol/L; When described ealkaline buffer is Tri(Hydroxymethyl) Amino Methane Hydrochloride, the pH value of the aqueous solution of described ealkaline buffer is 7.0 ~ 9.5.
13. preparation methods as claimed in claim 12, is characterized in that, the volumetric molar concentration of described reaction solution neutral and alkali buffer reagent is 0.3mol/L.
14. preparation methods as claimed in claim 1, it is characterized in that, in step (2), described stirring is at room temperature carried out, and described room temperature is 20 DEG C ~ 30 DEG C; Described reactor is three-necked flask, autoclave or sealed tube; The time of described reaction is 4h; The temperature of described reaction is 110 DEG C.
15. preparation methods as claimed in claim 14, it is characterized in that, described reaction is carried out in oil bath.
16. preparation methods as claimed in claim 1, is characterized in that, in step (2), after described cooling, also carry out post-processing operation, and described post-processing operation comprises washing, is separated and drying.
17. preparation methods as claimed in claim 16, is characterized in that, described washing is EtOH Sonicate washing and/or ultrapure water supersound washing; The described whizzer that is separated into is separated; Described drying is vacuum-drying 5h at 60 DEG C.
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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101665233A (en) * 2009-09-15 2010-03-10 北京化工大学 Layered double hydroxide and preparation method thereof
CN101817510A (en) * 2010-04-17 2010-09-01 湖州师范学院 Method for preparing hydrotalcite

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101665233A (en) * 2009-09-15 2010-03-10 北京化工大学 Layered double hydroxide and preparation method thereof
CN101817510A (en) * 2010-04-17 2010-09-01 湖州师范学院 Method for preparing hydrotalcite

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
Renzhi Ma et al..Synthesis and Exfoliation of Co2+-Fe3+ Layered Double Hydroxides: An Innovative Topochemical Approach.《J. AM. CHEM. SOC.》.2007,第129卷(第16期),第5257-5263页. *
Renzhi Ma et al..Topochemical Synthesis of Co-Fe Layered Double Hydroxides at Varied Fe/Co Ratios: Unique Intercalation of Triiodide and Its Profound Effect.《J. AM. CHEM. SOC.》.2010,第133卷(第3期),第613-620页. *
刘娅等.不同金属离子层状双氢氧化物制备及表征.《化学研究与应用》.2009,第21卷(第6期),第883-887页. *

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