CN104143643B

CN104143643B - A kind of fuel cell supported catalyst and application thereof

Info

Publication number: CN104143643B
Application number: CN201310167761.1A
Authority: CN
Inventors: 张华民; 柳丝丝; 钟和香; 邓呈维; 邱艳玲; 毛景霞
Original assignee: Dalian Institute of Chemical Physics of CAS
Current assignee: Dalian Institute of Chemical Physics of CAS
Priority date: 2013-05-09
Filing date: 2013-05-09
Publication date: 2016-06-15
Anticipated expiration: 2033-05-09
Also published as: CN104143643A

Abstract

The present invention relates to fuel-cell catalyst, specifically the application in a fuel cell of a kind of novel non-noble metal catalyst; The component of described catalyst is resorcinol, formaldehyde, and biological nitrogenous macromolecular compound is raw material. Resorcinol and formaldehyde mole ratio are 1:5～5:1, and biological nitrogenous macromolecular compound is the mass ratio of raw material and resorcinol is 30:1～1:30. Organogel carbonization in 500～1200 DEG C of inert gas environments prepares carbon gels carrier, and rear dipping cobalamine solution, then through highly active non-platinum catalyst pyrogenically prepared in 500～1200 DEG C of nitriding atmosphere environment. When the present invention is used as fuel battery cathod catalyst as a kind of non-metallic catalyst, show good oxygen reduction activity and electrochemical stability.

Description

A kind of fuel cell supported catalyst and application thereof

Technical field

The present invention relates to catalyst of fuel batter with proton exchange film, specifically the application in Proton Exchange Membrane Fuel Cells of the catalyst of a kind of novel non-noble metal. This non-precious metal catalyst can be used as fuel battery cathode with proton exchange film catalyst.

Technical background

Fuel cell is a kind of is directly the energy conversion device of electric energy by the chemical energy of material. Fuel cell does not work with heat engine form, and power generation process is not by the restriction of Carnot cycle, and the chemical energy of major part fuel therein can be converted directly into electric energy, and energy conversion efficiency can reach 40～60%. Meanwhile, fuel cell power generation process is nearly free from the harmful substances such as sulfur dioxide, nitrogen oxides and float, does not also release GHG carbon dioxide, meet society environmental protection concept. Meanwhile, needed for fuel cell, auxiliary equipment is few, eliminates a large amount of power transmission line, and convenient and reliable operation, motility are big. These advantages make fuel cell be acknowledged as the cleaning of 21 century first-selection, efficient generation technology, are subject to the great attention of national governments and enterprise in recent years.

Current eelctro-catalyst is as fuel cell critical material, and the stability of its material and preparation cost, electrochemical reaction activity and longtime running is to realize the obstacle that commercializing fuel cells is maximum. For common Proton Exchange Membrane Fuel Cells, the precious metal materials such as Pt are the catalyst materials being most widely used in PEMFC, the preparation technology of its limited resource, expensive price and complexity causes that the price of fuel cell can not be greatly lowered, and becomes the bottleneck of commercializing fuel cells. In recent years, no-Pt catalyst was once becoming emphasis and the focus of various countries fuel cell studies personnel research and development, and non-Pt oxygen reduction cathode catalyst mainly includes transition metal cluster compound, transition metal macrocyclic compound, transition metal oxide and transition metal carboritride etc. The good catalyst activity of no-Pt catalyst and cheap price become replacement Pt the strongest catalyst based being selected, yet with non-Pt material under the high potential weak acid of operation of fuel cells, alkali condition, very easily occur side reaction to cause the loss of catalyst, thus the distance practical application of stability aspect there is also very big gap. Therefore, for realizing the Commercialization application of fuel cell, develop a kind of high activity, high stability, cheap non-noble metal fuel cell cathod catalyst extremely urgent.

Material with carbon element relies on its cheap cost, abundant pore structure, suitable specific surface area and excellent heat-conductivity conducting performance, is widely used in the electro-catalyst carrier of fuel cell and the skeleton of porous gas diffusive electrode.Oxygen reduction reaction is not had an activity by material with carbon element itself, but the method for pyrolysis after passing through doping and modification or supporting nitrogen-containing compound, it is possible to prepared fuel battery negative pole non-platinum catalyst. Thus, develop a kind of novel non-noble metal catalyst, material cost will be greatly lowered, the business of fuel cell is applied significant.

Carbon xerogel material has the characteristics such as higher electric conductivity, bigger mesopore proportion, suitable specific surface area, it was commonly used as fuel cell carrier in the past, not only can support noble metal nano particles as catalyst, it is also possible to after supporting macrocyclic compound, non-platinum catalyst is prepared in pyrolysis. Therefore, on the carbon gel rubber material carrier prepared, support macrocyclic compound high temperature pyrolysis, it is possible to as fuel cell electro-catalyst, be substantially reduced catalyst material cost, promote the commercial applications of fuel cell.

Summary of the invention

It is an object of the invention to provide a kind of non-platinum catalyst and application in a fuel cell thereof; Carbon xerogel has bigger specific surface area, the central hole structure of appropriate substances transmission and good electrical and thermal conductivity performance, and biological nitrogenous macromolecular compound has wide material sources, lower-price characteristic, in combination with as fuel battery cathod catalyst, activity is high, good stability, helps speed up the commercialization process of proton exchange fuel cell.

For achieving the above object, the technical solution used in the present invention is:

A kind of fuel cell high activated catalyst, described catalyst is with resorcinol, formaldehyde, biological nitrogenous macromolecular compound for raw material, the nitrogenous macromolecular compound of described biology is one or two or more kinds in cobalamine, chlorophyll, haemachrome and derivant thereof, preferred cobalamine, adopts following process to be prepared from:

(1) by resorcinol and solvent orange 2 A in the ratio mixed preparing clear solution B of 0.1～10ml solvent/1g resorcinol;

(2) adding formalin in mixed solution, the mol ratio of resorcinol and formaldehyde is 1:1～4:1, and in 20～100 DEG C of environment, continuously stirred 1h～5h, is prepared into sol-gel precursor;

(3) in the sol-gel precursor that step (2) is obtained, when 20～70 DEG C, dropwise drop to liquid precursor with 0.5～2M ammonia or 0.5～2M oxalic acid and be cured as solid gel, obtain gel C.

(4) by dry for gel C burin-in process 3～12 days (preferred 5-8 days), attrition grinding after taking-up, pressed powder D is obtained;

(5) being processed 1～10 hour in 600～1200 DEG C of inert atmospheres by pressed powder D, inert atmosphere purges to room temperature and namely obtains carbon gel carrier;

(6) by biological nitrogenous macromolecular compound and solvent orange 2 A in the ratio mixed preparing solution E of 0.1～100ml solvent/1g cobalamine. Stir 0.5～4 hour under inert atmosphere protection.

(7) in the inner carbon gel carrier obtained of step (5), will join in the solution that step (6) is formed by the amount of the biological nitrogenous macromolecular compound of 0.1～10g carrier/1g, stir 0.5～4 hour under inert atmosphere protection. It is placed on heated and stirred solvent evaporated in 80 DEG C～100 DEG C water-baths or oil bath environment, obtains pressed powder F.

(8) being processed 1～10 hour in 500～1200 DEG C of nitriding atmospheres by the pressed powder F obtained in step (7), inert blowing gas is swept to room temperature and namely obtains non-precious metal catalyst.

Described dry aging method can be CO₂Supercritical drying, CO₂Supercritical drying condition 40～55 DEG C, 11～16Mpa, can obtain aeroge;Vacuum drying, vacuum drying condition 50～90 DEG C ,-0.1～-0.09Mpa, xerogel can be obtained; Or lyophilization, lyophilization Conditions Temperature, lower than solvent condensation point, normal pressure, can congeal glue.

When inert gas shielding or purging pressed powder are to room temperature, the volume mixture ratio that selected noble gas is one or two or more kinds in nitrogen, argon or carbon dioxide mixes gas arbitrarily.

Nitriding atmosphere is volume ratio is the NH of 5-90%₃/ N gaseous mixture, NH₃、CH₃The mixing gas that one or two or more kinds in CN or HCN mixes in any proportion.

Described non-precious metal catalyst all can be applied in PEM acidic fuel cell or alkaline membrane fuel cell.

Advantages of the present invention is:

1. application is effective. By preparing supported catalyst after nitrogenizing thermal decomposition process after adopting carbon gels to support biological nitrogenous macromolecular compound, catalysis is active and has good stability, and on fuel battery negative pole during application, shows long stability.

2. biological nitrogenous macromolecular compound has metal-N macrocyclic structure, metal-N fragment can be produced under pyrolytic conditions, this tile structure is according to the active center that reported literature is oxygen reduction catalyst, and these compounds wide material sources simultaneously, the catalyst performance prepared is good.

3. present invention process flow process is simple, the cycle is short, by the once carbonization simultaneously of precursor component, can prepare high-specific surface area, the carbon gels carrier of high stability; The solvent safety, nontoxic used in carbon gels preparation process, environmentally safe;

4. carbon gels of the present invention is in gel formation process, by regulating precursor solution concentration and reaction environment temperature, and carbonization nitrogen treatment temperature, can prepare pore structure and the controllable carbon gels carrier material of specific surface area.

5. catalyst of the present invention is with low cost, have wide range of applications, and greatly reduces the cost of fuel battery cathod catalyst, has great significance for production application.

Accompanying drawing explanation

Fig. 1 is the catalyst of non-pyrolysis after the supporting of embodiment 1 preparation, the oxidation virgin curve of carbon dust and catalyst; The condition of test polarization curves of oxygen reduction is: scanning electromotive force is interval: 0V to 0.9V, sweeps speed 5mV/s. Tested media is the 0.5M dilution heat of sulfuric acid that oxygen is saturated.

Fig. 2 is the stability test of the non-precious metal catalyst of embodiment 1 preparation; Adopting and accelerate decay scan mode, scanning electromotive force is interval :-0.2V arrives 0.9V, sweeps speed 50mV/s, 1000 circulations. The condition of rear test polarization curves of oxygen reduction is: scanning electromotive force is interval: 0V to 0.9V, sweeps speed 5mV/s. Tested media is the 0.5M dilution heat of sulfuric acid that oxygen is saturated.

Detailed description of the invention

The present invention is described in detail by the examples below, but the present invention is not limited only to embodiment.

Embodiment 1

6.16g resorcinol is dissolved in 7mL deionized water, forms clear solution B; In clear solution B, drip 9.08g mass concentration be the formalin of 37% and stir 5h, prepare sol-gel precursor. Dripping 3mL mass concentration in 20 DEG C of environment is 28% ammonia lasting seals stirring, and reaction forms gel C; Gel C is transferred to vacuum drying oven vacuum drying burin-in process 7d at 60 DEG C, attrition grinding after taking-up, obtains pressed powder D; Pressed powder D 800 DEG C of carbonization treatment 1h in nitrogen atmosphere are obtained required carbon gel carrier. Take 3.08g cobalamine and be dissolved in 20mL deionized water, add the carbon gel carrier for preparing of 6.16g, stir 2h under nitrogen protection, after under the water bath condition of 80 DEG C solvent evaporated, obtain supporting the carbon dust of cobalamine.By this carbon dust at NH₃Heat 2h in 700 DEG C under atmosphere, after purge with nitrogen and namely to obtain required catalyst to room temperature.

Comparative example 1

6.16g resorcinol is dissolved in 7mL deionized water, forms clear solution A; In clear solution A, drip 9.08g mass concentration be the formalin of 37% and stir 5h, prepare sol-gel precursor B. Dripping 3mL mass concentration in 20 DEG C of environment is 28% ammonia lasting seals stirring, and reaction forms gel C; Gel C is transferred to vacuum drying oven vacuum drying burin-in process 7d at 60 DEG C, attrition grinding after taking-up, obtains pressed powder D; Pressed powder D 800 DEG C of carbonization treatment 1h in nitrogen atmosphere are obtained required carbon gel carrier. Take 3.08g cobalamine and be dissolved in 20mL deionized water, add the 6.16 carbon gel carriers that prepare, stir 2h under nitrogen protection, after under the water bath condition of 80 DEG C solvent evaporated, obtain supporting the carbon dust contrast sample of cobalamine.

From the former activity curve of oxidation of Fig. 1 it can be seen that the carbon gels powdered carbon that original work are carrier is not have the former activity of oxidation. When supporting cobalamine but be nonheat-treated, show the former activity of certain oxidation. And through heat treated catalyst, catalysis activity increases substantially.

From the stability test of Fig. 2 it can be seen that this catalyst of preparation is relatively stable, after the circulation of 1000 circles, performance degradation is less.

Embodiment 2

6.16g resorcinol is dissolved in 7mL deionized water, forms clear solution A; In clear solution A, drip 9.08g mass concentration be the formalin of 37% and stir 5h, prepare sol-gel precursor B. Dripping 3mL mass concentration in 20 DEG C of environment is 28% ammonia lasting seals stirring, and reaction forms gel C; Gel C is transferred to vacuum drying oven vacuum drying burin-in process 7d at 60 DEG C, attrition grinding after taking-up, obtains pressed powder D; Pressed powder D 800 DEG C of carbonization treatment 1h in nitrogen atmosphere are obtained required carbon gel carrier. Take 6.16g cobalamine and be dissolved in 20mL deionized water, add the carbon gel carrier for preparing of 6.16g, stir 2h under nitrogen protection, after under the water bath condition of 80 DEG C solvent evaporated, obtain supporting the carbon dust of cobalamine. This carbon dust is heated 2h in 700 DEG C under acetonitrile atmosphere, after purge with nitrogen and namely to obtain required catalyst to room temperature.

Embodiment 3

6.16g resorcinol is dissolved in 7mL deionized water, forms clear solution A; In clear solution A, drip 9.08g mass concentration be the formalin of 37% and stir 5h, prepare sol-gel precursor B. Dripping 3mL mass concentration in 20 DEG C of environment is 28% ammonia lasting seals stirring, and reaction forms gel C; Gel C is transferred to vacuum drying oven vacuum drying burin-in process 7d at 60 DEG C, attrition grinding after taking-up, obtains pressed powder D; Pressed powder D 800 DEG C of carbonization treatment 1h in nitrogen atmosphere are obtained required carbon gel carrier. Take 2g cobalamine and be dissolved in 20mL deionized water, add the carbon gel carrier for preparing of 3.08g, stir 2h under nitrogen protection, after under the water bath condition of 80 DEG C solvent evaporated, obtain supporting the carbon dust of cobalamine. This carbon dust is heated 2h in 700 DEG C under ammonia atmosphere, after purge with nitrogen and namely to obtain required catalyst to room temperature.

Embodiment 4

6.16g resorcinol is dissolved in 7mL deionized water, forms clear solution A; In clear solution A, drip 9.08g mass concentration be the formalin of 37% and stir 5h, prepare sol-gel precursor B.Dripping 3mL mass concentration in 20 DEG C of environment is 28% ammonia lasting seals stirring, and reaction forms gel C; Gel C is transferred to vacuum drying oven vacuum drying burin-in process 7d at 60 DEG C, attrition grinding after taking-up, obtains pressed powder D; Pressed powder D 800 DEG C of carbonization treatment 1h in nitrogen atmosphere are obtained required carbon gel carrier. Take 3.08g cobalamine and be dissolved in 20mL deionized water, add the carbon gel carrier for preparing of 6.16g, stir 2h under nitrogen protection, after under the water bath condition of 80 DEG C solvent evaporated, obtain supporting the carbon dust of cobalamine. This carbon dust is heated 2h in 800 DEG C under NH3 atmosphere, after purge with nitrogen and namely to obtain required catalyst to room temperature.

Claims

1. a fuel cell supported catalyst, described catalyst is with resorcinol, formaldehyde, biological nitrogenous macromolecular compound for raw material, the nitrogenous macromolecular compound of described biology is one or two or more kinds in cobalamine, chlorophyll, haemachrome, adopts following process to be prepared from:

(1) by resorcinol and solvent orange 2 A in the ratio mixed preparing solution B of 0.1～10ml solvent/1g resorcinol;

(2) adding the mol ratio that mass concentration is the formalin of 20～40%, resorcinol and formaldehyde in solution B is 1:1～4:1, is stirred continuously until reaction and forms sol-gel precursor in 20～100 DEG C of environment;

(3) in the sol-gel precursor that step (2) is obtained, when 20～70 DEG C, dropwise drop to liquid precursor with 0.5～2M ammonia or 0.5～2M oxalic acid and be cured as solid gel, obtain gel C;

(4) gel C is dried burin-in process 3～12 days, attrition grinding after taking-up, obtain pressed powder D;

(5) being processed 1～10 hour in 600～1200 DEG C of inert atmospheres by pressed powder D, inert atmosphere gases purges to room temperature and namely obtains carbon gel carrier;

(6) by ratio mixed preparing solution E in the biological nitrogenous macromolecular compound of 0.1～100ml solvent/1g of biological nitrogenous macromolecular compound and solvent orange 2 A, inert atmosphere protection stirs 0.5～4 hour;

(7) will in the inner carbon gel carrier obtained of step (5), join in the solution that step (6) is formed by the amount of the biological nitrogenous macromolecular compound of 0.1～10g carrier/1g, inert atmosphere protection stirs 0.5～4 hour, it is placed on heated and stirred solvent evaporated in 80 DEG C～100 DEG C water-baths or oil bath, obtains pressed powder F;

(8) being processed 1～10 hour in 500～1200 DEG C of nitriding atmospheres by the pressed powder F obtained in step (7), inert atmosphere gases purges to room temperature and namely obtains required supported catalyst.

2. the supported catalyst described in claim 1, it is characterised in that: the gas that described inert atmosphere adopts is that the volume mixture ratio of one or two or more kinds in nitrogen, argon or carbon dioxide mixes gas arbitrarily.

3. the supported catalyst described in claim 1, it is characterised in that: described dry ageing method includes CO₂Supercritical drying, vacuum drying or lyophilization, wherein CO₂Supercritical drying condition is 40～55 DEG C, 11～16Mpa, obtains aeroge; Vacuum drying condition is 50～90 DEG C ,-0.1～-0.09Mpa, obtains xerogel; Lyophilization Conditions Temperature, lower than solvent condensation point, normal pressure, obtains congealing glue.

4. the supported catalyst described in claim 1, it is characterised in that: described solvent orange 2 A is one or more the mixture in water, ethanol, isopropanol or ethylene glycol;

Being 20～80 DEG C when solvent is ambient temperature during water, solvent is ambient temperature during ethanol is 20～78 DEG C, and solvent is ambient temperature during isopropanol is 20～82 DEG C, and solvent is the stirring ambient temperature of ethylene glycol is 60～100 DEG C;

When solvent orange 2 A is two or more mixture, ambient temperature is according to solvent environment temperature computation higher in mixture.

5. the supported catalyst described in claim 1, it is characterised in that: described nitriding atmosphere is volume ratio is the NH of 5-90%₃/N₂Gaseous mixture, NH₃、CH₃One or two or more kinds in CN or HCN.

6. one kind arbitrary in claim 1-5 as described in the application of supported catalyst, it is characterised in that: described supported catalyst as cathod catalyst in fuel battery cathode with proton exchange film.