A kind of metal organic framework Mn-BTC and preparation method and application
Technical field
The invention belongs to field of material technology, and in particular to a kind of metal organic framework and its microspheroidal manganese selenide/carbon are multiple
The preparation method of condensation material.
Background technique
With using petroleum as environmental pollution brought by the burning of the increasingly depleted and fossil energy of the fossil energy of representative
It gets worse, there is an urgent need to a kind of sustainable reproducible clean energy resourcies by people.And lithium ion battery is close with high-energy because of it
The advantages that degree, long circulation life, environment friendly, shows one's talent from numerous new energy, in mobile electronic device, new energy vapour
The fields such as vehicle have a wide range of applications.However, the negative electrode material of commercial Li-ion battery is graphite at present, the theoretical of graphite holds
Amount is only 372mAh/g, is unable to satisfy the capacity requirement of the large scale electronic equipments such as electric car, limits answering for lithium ion battery
With and development.Therefore scientist has developed capacity of a variety of negative electrode materials to improve lithium ion battery, such as Carbon Materials, transition
Metal oxide, transition metal sulfide, transition metal selenides etc..
Compared to transition metal oxide and transient metal sulfide, transition metal selenides not only has high volume ratio
Capacity and specific discharge capacity, and voltage platform is low polarize small, have preferable electric conductivity, be a kind of more potential lithium from
Sub- cell negative electrode material.However, similar with transition metal oxide, transition metal selenides is in charge and discharge process, due to lithium
The insertion and abjection of ion, it may occur that huge volume change leads to active material and collection to make active material breaking and Dusting
Fluid is detached from, and loses electrical contact, and capacity attenuation and cycle performance is caused to reduce.In addition, the electronic conduction of transition metal phosphide
Property is poor, hinders fast transfer of the electronics inside active material, limits its electrochemical response, leads to its fast charging and discharging
Ability and high rate performance are poor.
Currently, the research for improving transition metal selenides storage lithium performance is concentrated mainly on two aspects, one is by transition
The Carbon Materials such as metal selenide and graphene, carbon nanotube carry out it is compound, using the electric conductivity and mechanical performance that Carbon Materials are excellent,
Improve the electric conductivity of transition metal selenides and absorption cycle in the process because of stress caused by volume expansion;Another kind is to prepare
Transition metal selenides with nanoscale and porous structure expands the specific surface area of material, increases electrode material and electrolysis
The contact area of liquid shortens the diffusion path of electronics and lithium ion, and buffer volumes expand generated stress.
Metal organic framework compound, abbreviation MOFs are to pass through coordinate bond self assembly shape by organic ligand and metal ion
At the hybrid inorganic-organic materials with molecule hole.MOFs has porosity, bigger serface, component adjustability etc. excellent
Point, before making it that there is wide application in fields such as gas collection storage, gas separation, catalysis, sensor and energy storages
Scape has just had received widespread attention since last century the nineties are born.Simultaneously as the porous structure of MOFs and organic bone
The abundant adjustability of frame and metal ion makes it can be used as presoma to prepare porous material, such as Carbon Materials, metal oxygen
Compound, metal sulfide, metal selenide etc..Porous material derived from MOFs can retain porous structure possessed by MOFs and
Bigger serface, meanwhile, organic backbone can be changed into porous carbon under high temperature inert atmosphere, in the condition for not introducing external carbon source
Under can be prepared by porous carbon/metallic compound composite material.
Just at present apparently, the preparation of MOFs still has spherical imperfect, Cheng Banqiu or other are incomplete spherical or even broken
Being cleaved into fine particle can't see spherical morphology, and product poor dispersion is easy to happen the technical problems such as adhesion;And manganese selenide/carbon
Composite material there is also product purities not high, low yield, storage capacity is small, and cycle life is short, and use process stability is bad, holds
Easily it the technical problems urgent need to resolve such as electric current is suddenly big or suddenly small is in the presence of.
Summary of the invention
The present invention first is designed to provide the preparation method of metal organic framework Mn-BTC haveing excellent performance a kind of.
Second object of the present invention is to provide a kind of preparation method of microspheroidal manganese selenide/carbon composite.
The object of the invention is achieved through the following technical solutions:
A kind of preparation method of metal organic framework Mn-BTC, it is with Mn (CH3COO)2·4H2O, PVP-30, ethyl alcohol and water
Mixed solution, trimesic acid are raw material, and successively the preparation Jing Guo solution A, the preparation of solution B, mixing aging, centrifugation are washed respectively
It washs, be dried in vacuo.
Further, the preparation of above-mentioned solution A is to take Mn (CH3COO)2·4H2O and PVP-K30 are dissolved in ethyl alcohol and deionization
Setting 300 ~ 400 turns/min of revolving speed stirring and dissolving obtains mixed solution A in the mixed solution of water composition;Wherein state Mn (CH3COO)2·
4H2The mass ratio of O and PVP-K30 is 0.2449 ~ 0.4898:1 ~ 3, unit g/g;The PVP-K30 and ethyl alcohol and deionization
The mass volume ratio of the mixed solution of water composition is 1 ~ 3:100, unit g/ml.
Further, the preparation of above-mentioned solution B takes the mixed solution that trimesic acid is dissolved in ethyl alcohol and deionized water forms
In, it stirs so that being completely dissolved to obtain solution B;The quality of the mixed solution of the trimesic acid and ethyl alcohol and deionized water composition
Volume ratio is 0.6304 ~ 0.8994:100, unit g/ml.
Further, above-mentioned mixing aging is that solution A obtained above is taken to be added dropwise in solution B under agitation, is added dropwise
When revolving speed be 300 ~ 400 turns/min, continue to stir 10min ~ 20min, stop stirring, place aging 20 ~ for 24 hours at room temperature;Its
Described in the volume ratio of solution A and solution B be 1:100.
Further, above-mentioned centrifuge washing is that the product after above-mentioned aging is centrifuged, and collects centrifugation, then
Precipitating is washed 3 times with the mixed solution of ethyl alcohol and deionized water, collects precipitating, it is spare;Each dosage is 1:100 ~ 1:150, is
Volume ratio.
Further, above-mentioned vacuum drying is that precipitating obtained above is placed in 55 ~ 65 DEG C, air drying, dry 12 ~
15h, products therefrom are microspheroidal metal organic framework compound Mn-BTC, and white is presented in product, and shape is spherical.
Further, the mixed solution of above-mentioned ethyl alcohol and deionized water composition is ethyl alcohol and deionized water is 1:1 by volume
It is mixed to prepare.
A kind of preparation method of microspheroidal manganese selenide/carbon composite, which is characterized in that by microspheroidal gold obtained above
Belong to organic framework compounds Mn-BTC and selenium powder is individually positioned in the both ends of porcelain boat, then porcelain boat is placed in tube furnace, Mn-
BTC is in downstream, and selenium powder is in upstream, under an argon atmosphere, with heating rate is that 2 ~ 5 DEG C/min rises to 400 ~ 600 DEG C from room temperature, and
In 400 ~ 600 DEG C of 2 ~ 4h of heat preservation, microspheroidal manganese selenide/carbon composite can be obtained.
Further, the mass ratio of above-mentioned Mn-BTC and Se powder is 1:1 ~ 10.
The present invention have it is following the utility model has the advantages that
Metal organic framework prepared by the present invention has spherical morphology, and spherical morphology is complete, uniform, and good product dispersibility has no
Adhesion situation crystallinity is high.Using its prepare microspheroidal manganese selenide/carbon composite, microballoon regular appearance, pattern uniformly,
Good dispersion, specific surface area and porosity with higher;Excellent storage lithium performance is shown simultaneously, and product purity is high, purity
Up to 99.2%, yield is high, and up to 70% or more, storage capacity is big, has extended cycle life, in 100mA g-1Current density under
After 100 charge and discharge cycles, discharge capacity is 784 mAh g-1, storage capacity is big, has extended cycle life, and cycle-index is most
It can achieve less 100 times, at most can up to 200 times, it is not in the suddenly big or suddenly small situation of electric current that use process stability is good,
Process flow simple possible is worth marketing.
Detailed description of the invention
The SEM figure that Fig. 1 is microspheroidal metal organic framework compound Mn-BTC in the embodiment of the present invention 1.
Fig. 2 is microspheroidal manganese selenide/carbon composite SEM figure in the embodiment of the present invention 1.
Fig. 3 is microspheroidal manganese selenide/carbon composite XRD diagram in the embodiment of the present invention 1.
Fig. 4 is for microspheroidal manganese selenide/carbon composite in the embodiment of the present invention 1 as lithium cell negative pole material in 100mA/g
Current density under cyclic curve figure.
Specific embodiment
The present invention is specifically described below by embodiment, it is necessary to which indicated herein is that following embodiment is only used
In invention is further explained, it should not be understood as limiting the scope of the invention, person skilled in art can
To make some nonessential modifications and adaptations to the present invention according to aforementioned present invention content.
Embodiment 1:
The preparation of microspheroidal metal organic framework compound Mn-BTC: 2mmol Mn (CH is weighed3COO)2·4H2O and 3gPVP
(K30), the mixed solution (v:v=1:1) of 100ml ethyl alcohol and deionized water is dissolved in the case where revolving speed is 350 turns/min stirring condition
In, 4.28mmol trimesic acid is weighed, is dissolved in 100 ml ethyl alcohol and the mixed solution (v:v=1:1) of deionized water, stirs
Mixing revolving speed is 350 turns/min, it is to be mixed be completely dissolved after, using the liquid-transfering gun of 1ml by Mn (CH3COO)2·4H2O solution instills
In trimesic acid solution, speed of agitator be 350 turns/min, stir 10min, stop stirring after at room temperature aging for 24 hours, by product
Centrifuge separation, wash 3 times with the mixed solution (v:v=1:1) of ethyl alcohol and deionized water, each dosage be precipitating, ethyl alcohol with go from
The volume ratio of the mixed solution of sub- water is 1:120, is subsequently placed at 60 DEG C of vacuum drying 12h, products therefrom is microspheroidal metal
Organic framework compounds Mn-BTC, product are presented white, shape be it is spherical, there is spherical morphology, good product dispersibility has no viscous
Even situation crystallinity is high.
Embodiment 2:
Microspheroidal metal organic framework compound Mn-BTC and Se powder prepared by embodiment 1 is put respectively according to the mass ratio of 1:10
It setting at the both ends of porcelain boat, then porcelain boat is placed in tube furnace, Mn-BTC is in downstream, and Se powder is in upstream, under an argon atmosphere,
It is that 3 DEG C/min rises to 450 DEG C from room temperature, and in 450 DEG C of heat preservation 3h, obtains microspheroidal manganese selenide/carbon composite wood with heating rate
Material.
Microspheroidal manganese selenide/carbon composite of preparation, maintains the microspheroidal of metal organic framework compound well
Pattern, crystallinity is high, specific surface area and porosity with higher, shows excellent storage lithium performance, and product purity is high, can be high
Up to 99.2%.
The results showed that microspheroidal manganese selenide/carbon composite prepared by the present invention has excellent storage lithium performance,
100mA g-1Current density under after 100 charge and discharge cycles, discharge capacity be 784mAh g-1, demonstrate,proved by experiment
Real, recyclable 200 times unattenuated.Illustrate that microspheroidal manganese selenide/carbon composite offer high-specific surface area and porosity are advantageous
In increasing response area, promote the transmitting of electronics and ion, while the presence of carbon can alleviate answering of generating in charge and discharge process
Power, and then effectively improve storage lithium performance.
Embodiment 3:
A kind of preparation method of microspheroidal manganese selenide/carbon composite, comprising the following steps:
1. the preparation of microspheroidal metal organic framework compound Mn-BTC: weighing 2 mmol Mn (CH3COO)2·4H2O and 3 g
PVP (K30), be dissolved in the case where revolving speed is 400 turns/min stirring condition 100ml ethyl alcohol and deionized water mixed solution (v:v=
In 1:1), 4.28 mmol trimesic acids are weighed, are dissolved in the mixed solution (v:v=1:1) of 100 ml ethyl alcohol and deionized water
In, speed of agitator is 400 turns/min, it is to be mixed be completely dissolved after, using the liquid-transfering gun of 1ml by Mn (CH3COO)2·4H2O solution
It instills in trimesic acid solution, speed of agitator is 400 turns/min, stirs 10min, aging for 24 hours, will at room temperature after stopping stirring
Product centrifuge separation, wash 3 times with the mixed solution (v:v=1:1) of ethyl alcohol and deionized water, each dosage be precipitating, ethyl alcohol and
The volume ratio of the mixed solution of deionized water is 1:150, is subsequently placed at 60 DEG C of vacuum drying 12h, products therefrom is microspheroidal
White is presented in metal organic framework compound Mn-BTC, product, and shape is spherical;
2. microspheroidal manganese selenide/carbon composite preparation based on above-mentioned skeleton: microspheroidal metal prepared by step 1) is had
Machine framework compound Mn-BTC and Se powder are individually positioned in the both ends of porcelain boat according to the mass ratio of 1:6, are then placed in porcelain boat
In tube furnace, Mn-BTC is in downstream, and Se powder is in upstream, is that 2 DEG C/min rises to from room temperature with heating rate under an argon atmosphere
500 DEG C, and in 500 DEG C of heat preservation 2h, obtain microspheroidal manganese selenide/carbon composite.
Microspheroidal manganese selenide/carbon composite of preparation, maintains the microspheroidal of metal organic framework compound well
Pattern, crystallinity is high, specific surface area and porosity with higher, shows excellent storage lithium performance, and product purity is high, can be high
Up to 99.1%, storage capacity is big, has extended cycle life, at least 100 times recyclable, and 200 unattenuated, uses at most can be recycled
Process stability is good, is not in the suddenly big or suddenly small situation of electric current.
Embodiment 4:
A kind of preparation method of microspheroidal manganese selenide/carbon composite, comprising the following steps:
1. the preparation of microspheroidal metal organic framework compound Mn-BTC: weighing 2mmol Mn (CH3COO)2·4H2O and 3gPVP
(K30), the mixed solution (v:v=1:1) of 100ml ethyl alcohol and deionized water is dissolved in the case where revolving speed is 300 turns/min stirring condition
In, 4.28mmol trimesic acid is weighed, is dissolved in 100 ml ethyl alcohol and the mixed solution (v:v=1:1) of deionized water, stirs
Mixing revolving speed is 300 turns/min, it is to be mixed be completely dissolved after, using the liquid-transfering gun of 1ml by Mn (CH3COO)2·4H2O solution instills
In trimesic acid solution, speed of agitator be 300 turns/min, stir 10min, stop stirring after at room temperature aging for 24 hours, by product
Centrifuge separation, wash 3 times with the mixed solution (v:v=1:1) of ethyl alcohol and deionized water, each dosage be precipitating, ethyl alcohol with go from
The volume ratio of the mixed solution of sub- water is 1:100, is subsequently placed at 60 DEG C of vacuum drying 12h, products therefrom is microspheroidal metal
White is presented in organic framework compounds Mn-BTC, product, and shape is spherical;
2. microspheroidal manganese selenide/carbon composite preparation based on above-mentioned organic backbone: by the microspheroidal gold of step 1) preparation
Belong to organic framework compounds Mn-BTC and Se powder is individually positioned in the both ends of porcelain boat according to the mass ratio of 1:8, then puts porcelain boat
It is placed in tube furnace, Mn-BTC is in downstream, and Se powder is in upstream, is 5 DEG C/min from room temperature liter with heating rate under an argon atmosphere
To 550 DEG C, and in 450 DEG C of heat preservation 2h, microspheroidal manganese selenide/carbon composite is obtained.
Microspheroidal manganese selenide/carbon composite of preparation, maintains the microspheroidal of metal organic framework compound well
Pattern, crystallinity is high, specific surface area and porosity with higher, shows excellent storage lithium performance, and product purity is high, can be high
Up to 99.1%, storage capacity is big, has extended cycle life, at least 100 times recyclable, and 200 unattenuated, uses at most can be recycled
Process stability is good, is not in the suddenly big or suddenly small situation of electric current.