A kind of preparation method of platinum/graphen-perovskite-foamed nickel catalyst agent
Technical field
The present invention relates to the preparation sides that a kind of Pt metal is carried on the catalyst in graphene-perovskite-foam nickel carrier
Method belongs to catalyst field.
Background technique
LaFeO3 is a kind of typically with perovskite (ABO3) structure rare earth metal composite oxide, the Ca-Ti ore type
Compound has and can have more Lacking oxygen and good thermal stability, and B ions are with mixed while keeping structure
The advantages that closing valence state and abnormal valence state, and being concerned in catalytic field, preparation method mainly have auto-combustion method, hydro-thermal method,
Sol-gel method, solid phase method, coprecipitation, chemical vapour deposition technique, drop leaching-pyrolysismethod, microemulsion method and wet chemistry method
Deng, preparating mechanism and process conditions, there were significant differences, and the catalysis material surface property and structure for causing distinct methods to prepare are poor
Different very big, but all perovskites have an obvious shortcoming, i.e., extremely low (usual specific surface area is in 3-5m for specific surface area2/ g) and
Limit use of the perovskite in catalytic field.
Graphene as it is presently found it is most thin, maximum intensity is conductive, heating conduction, the strongest one kind of optical property are novel
(such as pure grapheme material, surface area can reach 2000 ~ 4000m to nano material2/ g) it is very promising catalyst carrier, but
Current technology is difficult on a large scale, high-quality, and inexpensive prepares grapheme material, and seriously constrains graphene in the industry
Application.There are many methods to be developed at present and prepares the dilute compound of graphite.Especially by the dilute side of reduction-oxidation graphite
Method may be implemented high-volume, low cost to prepare graphite dilute, and the dilute surface of graphite oxide can also be made full use of abundant oxygen-containing
Functional group, thus further to its functionalization to adjust the performance that graphite oxide is dilute or reduction-oxidation graphite is dilute.So far, stone
Ink refining is successfully compound with inorganic nanoparticles, organic crystal, polymer, metal organic complex, biomaterial etc., this
A little dilute composite materials of graphite are widely used in lithium ion battery, supercapacitor, fuel cell, photocatalysis, biosensor
Etc..In addition, being rarely reported for the preparation of graphene-perovskite compound, mainly since perovskite is in preparation process
In be usually required to 300-700 DEG C of roasting, can be formed under high temperature, but graphene is as carbon material, usually less than
150 DEG C will burn totally (pure graphene, aerial ignition temperature are relatively higher).
Furthermore, it is however generally that common noble metal has palladium, platinum, ruthenium, silver, rhodium, wherein especially most with platinum, rhodium noble metal application surface
Extensively.For transition elements noble metal catalyst, d electron orbit is all unfilled, the easy adsorption reaction object gas molecule in surface, and strong
It spends moderate, advantageously forms " reactive compound " intermediate state, show higher catalytic activity, while also there is high temperature resistant, anti-
The comprehensive good characteristic such as oxidation, corrosion-resistant, and become important catalyst activity component, but noble metal is due to earth reserves
Less, expensive to hinder its method application, and for noble metal/perovskite catalyst, due to the specific surface of perovskite
Product is lower, and noble metal usually can all reunite and reduce catalytic activity.In addition, for gas-solid catalysis, a such as oxidation
For carbon preferential oxidation, Oxidation of Carbon Monoxide, hydrogen production by ethanol steam reforming reaction, synthesis gas prepare the reaction of low-carbon alcohol catalysis,
Although the unique mesopore orbit structure of catalyst has great advantage in terms of Selective Separation, it will limit molecule and quickly expand
It dissipates, is unfavorable for the generation of intended catalyzed reaction, but macropore is conducive to quickly spread, be in progress in terms of mass-and heat-transfer significant, therefore
It is proposed the mesoporous and compound composite material of macropore multi-stage porous.
Summary of the invention
The invention proposes a kind of preparation method of platinum/graphen-perovskite-foamed nickel catalyst agent, deposited in the catalyst
Micropore-mesopore between graphene-graphene, the slit pore between graphene and perovskite, the macropore between perovskite and perovskite,
The macropore of nickel foam, the i.e. catalyst possess micropore-mesopore-macropore hierarchical porous structure simultaneously, and by strike, so that
The surface of the uniform load carriers of Pt nano particle, catalytic activity are much higher than similar catalyst, pass through the limited solution of hydro-thermal method
It has determined the low problem of surface area of the Complex Problem of graphene and perovskite, perovskite, has prepared that introduce macropore effective by electrode
Solve carbon monoxide preferential oxidation in hydrogen-rich gas, Oxidation of Carbon Monoxide, hydrogen production by ethanol steam reforming reaction, synthesis gas
A series of mass transfer problem of vapor solids such as low-carbon alcohol catalysis reaction is prepared, and your gold of electrodeposition process effective solution used
Belong to the problem easy to reunite in catalyst surface.
Platinum/graphen-perovskite-foamed nickel catalyst the agent the preparation method comprises the following steps:
(1) graphite oxide aqueous solution is prepared using hummer method, the brown color graphite oxide for obtaining 0.5-2mg/mL is water-soluble
Liquid;
(2) using above-mentioned graphene oxide water solution as solvent, La (NO is sequentially added thereto3)3.6H2O, NaOH and
Na2CO3, magnetic agitation 1h at 10-15 DEG C obtains brownish red suspension;
(3) special high temperature resistant, high pressure, alkali corrosion hydrothermal reaction kettle, sealing is added in above-mentioned brown liquid;Then to
It is passed through inert gas in reaction kettle, for emptying the air in reaction kettle, opens the matched agitating device of reaction kettle, is stirred at room temperature
30 minute, it is then shut off the valve of inert gas, hydrothermal reaction kettle is fully sealed, sets heating mantle in hydrothermal reaction kettle surrounding,
Setting program heating;
(4) when temperature reaches 260 DEG C ~ 320 DEG C 12 ~ 48h of constant temperature, removal heating mantle is slowly cooled to room temperature, opens hydro-thermal
Reaction kettle obtains grey black solution;
(5) grey black solution is filtered, is successively filtered by vacuum, supersound washing obtains grey black sediment, and 40 DEG C of drying obtain
Clean grey black graphene-LaFeO3Powder;
(6) by electrically conductive graphite, binder, graphene-LaFeO3Powder mixing is suppressed under 3Mpa pressure in nickel foam
On, 40 DEG C of drying obtain flake graphite alkene-LaFeO3Foam nickel electrode;
(7) using the electrode prepared as working electrode, it is to electrode with platinum-base material, is 5% with mass fraction
H2PtCl6.6H2O or Pt (NH3)2(NO2)2For electrolyte, current density 1-2A/dm3, time 1-2h, 25 ~ 30 DEG C of temperature exists
Flake graphite alkene-LaFeO3Uniform deposition platinum sodium rice particle on foam nickel electrode obtains Pt/ graphene-LaFeO3Nickel foam is urged
Agent.
Wherein La (NO3)3.6H2O:NaOH:Na2CO3Molar ratio be 1:10 ~ 15:3 ~ 6.
Wherein temperature-programmed mode are as follows: be warming up to 100 DEG C first with the heating rate of 1 ~ 2 DEG C/min, kept for 1 hour, so
1 ~ 2 DEG C/min is warming up to 260 ~ 320 DEG C afterwards, is kept for 12 ~ 48 hours, terminates.
The mode being wherein filtered by vacuum is to be filtered using water-ring vacuum pump, and the mode of supersound washing is successively to use quality
The dilute hydrochloric acid that score is 5 ~ 7%, anhydrous propanone, dehydrated alcohol, deionized water are repeatedly washed.
Electrically conductive graphite, binder, graphene-LaFeO3The mass ratio of powder is 1:1:8 mixing, is ground in the agate mortar
Mill, and it is uniform that appropriate dehydrated alcohol mixing paste is added, and it was evenly coated in nickel foam.
Wherein electrolyte may be H2PtCl6.6H2O and NiSO4Mixture, mass ratio be 1:3 be used to form Pt-
Ni/ graphene-LaFeO3Foamed nickel catalyst agent.
In addition, the catalyst can be used for carbon monoxide preferential oxidation in hydrogen-rich gas, Oxidation of Carbon Monoxide, ethanol steam
Reformation hydrogen production reaction, synthesis gas are prepared in the reaction of low-carbon alcohol catalysis, are existed before the use process of catalyst using reducibility gas
Reduction treatment under conditions of lower than 150 ~ 200 DEG C, only using hydrogen-rich gas CO preferential oxidation as example in embodiment.
Figure of description
Table 1 is the specific surface area and Particle size data of catalyst and comparative example;
Fig. 1 is catalyst and comparative example activity data figure.
Specific embodiment
The catalyst performance condition that CO-PROX reacts in hydrogen-rich atmosphere are as follows: in H before reaction2/N2300 in gaseous mixtureoC
Reduction pretreatment 1 hour.Corresponding volume space velocity is 24000ml/gcat.H, unstrpped gas group become 1 vol.% CO, and 1
vol.% O2, 50 vol.% H2, 0-12.5 vol.% CO2, 0-15 vol.% H2O and N2Balance Air.
Comparative example 1
No. 1-roasting method prepares LaFeO3- infusion process supporting Pt:
By the lanthanum nitrate of special ratios, ferric nitrate is dissolved in deionized water, and a certain proportion of lemon is added into mixed solution
Lemon acid and ethylene glycol, 85oStirring is to whole dissolutions under C, and 120oC oven drying for 24 hours, 600o2h is roasted under C, obtains LaFeO3, connect
Using six hydration chloroplatinic acids of solution dipping method dipping, it is dry to obtain Pt/LaFeO3, i.e. No. 1 catalyst.
Comparative example 2
No. 2-Hummer prepare graphene-infusion process supporting Pt:
Hummer is conventional method, is filtered, washed, dries, six hydration chloroplatinic acid of dipping, dry to obtain Pt/ graphene, i.e.,
No. 2 catalyst, theoretically activity should be very high, but during actually preparation, due to repeatedly washing drying, so that original point
Scattered graphene sheet layer is reunited again, causes surface area very low, and graphene itself, without macropore, mass transfer is seriously obstructed, and finally makes
It is very low to obtain catalytic activity.
Comparative example 3
No. 3-hydro-thermal method prepares compound-infusion process supporting Pt:
Graphene-LaFeO is prepared using the consistent hydro-thermal method of the application3Carrier, six hydration chloroplatinic acid of dipping are dry to obtain
Pt/ graphene-LaFeO3, i.e. No. 3 catalyst, active effect is relatively low, be primarily due to carrier itself be not present it is more
Macropore, cause gas transfer to be obstructed, and the dispersibility of infusion process supporting Pt is poor, reunites, particle radius is larger.
Embodiment 4
No. 4-hydro-thermal method prepares compound-nickel foam-electro-deposition preparation supporting Pt:
(1) graphite oxide aqueous solution is prepared using hummer method first, obtains the brown color graphite oxide water of 1.5mg/mL
Solution;(2) using above-mentioned graphene oxide water solution as solvent, the La (NO that molar ratio is 1:15:6 is sequentially added thereto3)3 .6H2O, NaOH and Na2CO3, 15oMagnetic agitation 1h under C obtains brownish red suspension;(3) above-mentioned brown liquid is added
Special high temperature resistant, high pressure, alkali corrosion hydrothermal reaction kettle, sealing;Then inert gas is passed through into reaction kettle, it is anti-for emptying
The air in kettle is answered, the matched agitating device of reaction kettle is opened, is stirred at room temperature 30 minutes, is then shut off the valve of inert gas,
Hydrothermal reaction kettle is fully sealed, sets heating mantle, setting program heating: 1 in hydrothermal reaction kettle surroundingoThe heating rate of C/min
It is warming up to 100oC, is kept for 1 hour, and then 1oC/min is warming up to 260oC, keeps reaching 260 when temperature in 12 hours (4)oC constant temperature
12 ~ 48h removes heating mantle, is slowly cooled to room temperature, and opens hydrothermal reaction kettle, obtains grey black solution;(5) grey black is filtered
Solution is successively filtered by vacuum, supersound washing acquisition grey black sediment, and 40oC drying obtains clean grey black graphene-
LaFeO3Powder;(6) by electrically conductive graphite, binder, graphene-LaFeO3Powder mixing is suppressed under 3Mpa pressure in foam
On nickel, 40oC drying, obtains flake graphite alkene-LaFeO3Foam nickel electrode;(7) using the electrode prepared as working electrode,
It is the H for being 1% with mass fraction to electrode with platinum-base material2PtCl6.6H2Or Pt (NH3)2(NO2) 2 be electrolyte, current density
For 2A/dm3, time 1h, temperature 30oC is in flake graphite alkene-LaFeO3Uniform deposition platinum sodium rice particle, is obtained on foam nickel electrode
Obtain Pt/ graphene-LaFeO3Foamed nickel catalyst agent.
Embodiment 5
No. 4-hydro-thermal method prepares compound-nickel foam-electro-deposition preparation supporting Pt:
(1) graphite oxide aqueous solution is prepared using hummer method first, the brown color graphite oxide for obtaining 2mg/mL is water-soluble
Liquid;(2) using above-mentioned graphene oxide water solution as solvent, the La (NO that molar ratio is 1:15:6 is sequentially added thereto3)3 .6H2O, NaOH and Na2CO3, 15oMagnetic agitation 1h under C obtains brownish red suspension;(3) above-mentioned brown liquid is added
Special high temperature resistant, high pressure, alkali corrosion hydrothermal reaction kettle, sealing;Then inert gas is passed through into reaction kettle, it is anti-for emptying
The air in kettle is answered, the matched agitating device of reaction kettle is opened, is stirred at room temperature 30 minutes, is then shut off the valve of inert gas,
Hydrothermal reaction kettle is fully sealed, sets heating mantle, setting program heating: 1 in hydrothermal reaction kettle surroundingoThe heating rate of C/min
It is warming up to 100oC, is kept for 1 hour, and then 1oC/min is warming up to 280oC, keeps reaching 260 when temperature in 12 hours (4)oC constant temperature
12 ~ 48h removes heating mantle, is slowly cooled to room temperature, and opens hydrothermal reaction kettle, obtains grey black solution;(5) grey black is filtered
Solution is successively filtered by vacuum, supersound washing acquisition grey black sediment, and 40oC drying obtains clean grey black graphene-
LaFeO3Powder;(6) by electrically conductive graphite, binder, graphene-LaFeO3Powder mixing is suppressed under 3Mpa pressure in foam
On nickel, 40oC drying, obtains flake graphite alkene-LaFeO3Foam nickel electrode;(7) using the electrode prepared as working electrode,
It is the H for being 3% with mass fraction to electrode with platinum-base material2PtCl6.6H2Or Pt (NH3)2(NO2) 2 be electrolyte, current density
For 2A/dm3, time 1h, temperature 30oC is in flake graphite alkene-LaFeO3Uniform deposition platinum sodium rice particle, is obtained on foam nickel electrode
Obtain Pt/ graphene-LaFeO3Foamed nickel catalyst agent.
Embodiment 6
No. 4-hydro-thermal method prepares compound-nickel foam-electro-deposition preparation supporting Pt:
(1) graphite oxide aqueous solution is prepared using hummer method first, the brown color graphite oxide for obtaining 2mg/mL is water-soluble
Liquid;(2) using above-mentioned graphene oxide water solution as solvent, the La (NO that molar ratio is 1:15:6 is sequentially added thereto3)3 .6H2O, NaOH and Na2CO3, 15oMagnetic agitation 1h under C obtains brownish red suspension;(3) above-mentioned brown liquid is added
Special high temperature resistant, high pressure, alkali corrosion hydrothermal reaction kettle, sealing;Then inert gas is passed through into reaction kettle, it is anti-for emptying
The air in kettle is answered, the matched agitating device of reaction kettle is opened, is stirred at room temperature 30 minutes, is then shut off the valve of inert gas,
Hydrothermal reaction kettle is fully sealed, sets heating mantle, setting program heating: 1 in hydrothermal reaction kettle surroundingoThe heating rate of C/min
It is warming up to 100oC, is kept for 1 hour, and then 1oC/min is warming up to 300oC, keeps reaching 260 when temperature in 12 hours (4)oC constant temperature
12 ~ 48h removes heating mantle, is slowly cooled to room temperature, and opens hydrothermal reaction kettle, obtains grey black solution;(5) grey black is filtered
Solution is successively filtered by vacuum, supersound washing acquisition grey black sediment, and 40oC drying obtains clean grey black graphene-
LaFeO3Powder;(6) by electrically conductive graphite, binder, graphene-LaFeO3Powder mixing is suppressed under 3Mpa pressure in foam
On nickel, 40oC drying, obtains flake graphite alkene-LaFeO3Foam nickel electrode;(7) using the electrode prepared as working electrode,
It is the H for being 5% with mass fraction to electrode with platinum-base material2PtCl6.6H2Or Pt (NH3)2(NO2) 2 be electrolyte, current density
For 2A/dm3, time 1h, temperature 30oC is in flake graphite alkene-LaFeO3Uniform deposition platinum sodium rice particle, is obtained on foam nickel electrode
Obtain Pt/ graphene-LaFeO3Foamed nickel catalyst agent.
Embodiment 7
No. 4-hydro-thermal method prepares compound-nickel foam-electro-deposition preparation supporting Pt:
(1) graphite oxide aqueous solution is prepared using hummer method first, the brown color graphite oxide for obtaining 2mg/mL is water-soluble
Liquid;(2) using above-mentioned graphene oxide water solution as solvent, the La (NO that molar ratio is 1:15:6 is sequentially added thereto3)3 .6H2O, NaOH and Na2CO3, 15oMagnetic agitation 1h under C obtains brownish red suspension;(3) above-mentioned brown liquid is added
Special high temperature resistant, high pressure, alkali corrosion hydrothermal reaction kettle, sealing;Then inert gas is passed through into reaction kettle, it is anti-for emptying
The air in kettle is answered, the matched agitating device of reaction kettle is opened, is stirred at room temperature 30 minutes, is then shut off the valve of inert gas,
Hydrothermal reaction kettle is fully sealed, sets heating mantle, setting program heating: 1 in hydrothermal reaction kettle surroundingoThe heating rate of C/min
It is warming up to 100oC, is kept for 1 hour, and then 1oC/min is warming up to 320oC, keeps reaching 260 when temperature in 12 hours (4)oC constant temperature
12 ~ 48h removes heating mantle, is slowly cooled to room temperature, and opens hydrothermal reaction kettle, obtains grey black solution;(5) grey black is filtered
Solution is successively filtered by vacuum, supersound washing acquisition grey black sediment, and 40oC drying obtains clean grey black graphene-
LaFeO3Powder;(6) by electrically conductive graphite, binder, graphene-LaFeO3Powder mixing is suppressed under 3Mpa pressure in foam
On nickel, 40oC drying, obtains flake graphite alkene-LaFeO3Foam nickel electrode;(7) using the electrode prepared as working electrode,
It is the H for being 7% with mass fraction to electrode with platinum-base material2PtCl6.6H2Or Pt (NH3)2(NO2) 2 be electrolyte, current density
For 2A/dm3, time 1h, temperature 30oC is in flake graphite alkene-LaFeO3Uniform deposition platinum sodium rice particle, is obtained on foam nickel electrode
Obtain Pt/ graphene-LaFeO3Foamed nickel catalyst agent.
Embodiment 8
No. 4-hydro-thermal method prepares compound-nickel foam-electro-deposition preparation supporting Pt:
(1) graphite oxide aqueous solution is prepared using hummer method first, the brown color graphite oxide for obtaining 2mg/mL is water-soluble
Liquid;(2) using above-mentioned graphene oxide water solution as solvent, the La (NO that molar ratio is 1:15:6 is sequentially added thereto3)3 .6H2O, NaOH and Na2CO3, 15oMagnetic agitation 1h under C obtains brownish red suspension;(3) above-mentioned brown liquid is added
Special high temperature resistant, high pressure, alkali corrosion hydrothermal reaction kettle, sealing;Then inert gas is passed through into reaction kettle, it is anti-for emptying
The air in kettle is answered, the matched agitating device of reaction kettle is opened, is stirred at room temperature 30 minutes, is then shut off the valve of inert gas,
Hydrothermal reaction kettle is fully sealed, sets heating mantle, setting program heating: 1 in hydrothermal reaction kettle surroundingoThe heating rate of C/min
It is warming up to 100oC, is kept for 1 hour, and then 1oC/min is warming up to 320oC, keeps reaching 260 when temperature in 12 hours (4)oC constant temperature
12 ~ 48h removes heating mantle, is slowly cooled to room temperature, and opens hydrothermal reaction kettle, obtains grey black solution;(5) grey black is filtered
Solution is successively filtered by vacuum, supersound washing acquisition grey black sediment, and 40oC drying obtains clean grey black graphene-
LaFeO3Powder;(6) by electrically conductive graphite, binder, graphene-LaFeO3Powder mixing is suppressed under 3Mpa pressure in foam
On nickel, 40oC drying, obtains flake graphite alkene-LaFeO3Foam nickel electrode;(7) using the electrode prepared as working electrode,
It is to electrode with platinum-base material, is the H of 1:3 with mass ratio2PtCl6.6H2And NiSO4For electrolyte (total quality is 7%), electricity
Current density is 2A/dm3, time 1h, temperature 30oC is in flake graphite alkene-LaFeO3Uniform deposition platinum sodium rice on foam nickel electrode
Particle obtains Pt-Ni/ graphene-LaFeO3Foamed nickel catalyst agent.
The above is only a preferred embodiment of the present invention, for those of ordinary skill in the art, according to the present invention
Thought, there will be changes in the specific implementation manner and application range, and the content of the present specification should not be construed as to the present invention
Limitation.