氟掺杂多孔聚合物的制备及其吸附性能

赵宏伟; 陈广; 彭琪; 王瑞元; 曹新秀; 刘欢; 刘清泉

doi:10.13801/j.cnki.fhclxb.20220302.002

氟掺杂多孔聚合物的制备及其吸附性能

doi: 10.13801/j.cnki.fhclxb.20220302.002

赵宏伟^{1, 2,},
陈广¹,
彭琪¹,
王瑞元¹,
曹新秀^{1, 2},
刘欢^{1, 2},
刘清泉^{1, 2, ,}

1.
湖南科技大学　材料科学与工程学院，湘潭 411201
2.
湖南省新能源储存与转换先进材料重点实验室，湘潭 411201

基金项目: 国家自然科学基金(51778226；22008060)；湖南省自然科学基金(2020JJ5196)

详细信息

通讯作者:
刘清泉，博士，教授，博士生导师，研究方向为微孔有机高分子材料的设计、合成及应用　 E-mail: qqliu@hnust.edu.cn

中图分类号: TB331
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- 被引次数: 0
出版历程
- 收稿日期: 2021-12-29
- 修回日期: 2022-01-17
- 录用日期: 2022-01-22
- 网络出版日期: 2022-03-05
- 刊出日期: 2022-08-31

Preparation and adsorption properties of fluorine-doped porous polymers

ZHAO Hongwei^{1, 2
,},
CHEN Guang¹,
PENG Qi¹,
WANG Ruiyuan¹,
CAO Xinxiu^{1, 2},
LIU Huan^{1, 2},
LIU Qingquan^{1, 2
, ,}

1.
School of Materials Science and Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
2.
Hunan Provincial Key Lab of Advanced Materials for New Energy Storage and Conversion, Xiangtan 411201, China

摘要

摘要: 共轭微孔聚合物(CMPs)由于其稳定的孔隙结构、多样的合成方法及在气体吸附、废水染料吸附等领域的应用受到了广泛关注。设计并合成了两种氟掺杂共轭微孔聚合物：首先合成了两种含氟构筑单元1,3,5-三氟-2,4,6-三乙炔基苯(FAB)和5,10,15,20-四(2-氟-4-乙炔基苯基)卟啉(TFPP)。分别以FAB和TFPP为构筑单元，以1,1’-二溴二茂铁(Fc(Br)₂)为链接单元，基于Sonogashira偶联反应，成功制备了两种氟掺杂多孔聚合物氟掺杂多孔聚合物二茂铁基(Fc)-FAB-CMP 和 Fc-TFPP-CMP。并进一步对两种多孔聚合物的化学结构、热稳定性、孔隙结构、气体及染料吸附性能等方面进行了详细的分析。结果表明，两种聚合物均表现出良好的热稳定性。Fc-FAB-CMP和 Fc-TFPP-CMP的BET比表面积分别为302.89 m²/g和125.2 m²/g，其中Fc-FAB-CMP表现出更加优异的气体吸附性能。此外，二茂铁单元与氟取代基的引入可成为阳离子染料甲基紫(MV)的吸附位点，Fc-FAB-CMP相较于许多更高比表面积的聚合物表现出对MV更优异的吸附能力，最大吸附量可达318 mg/g。
- 多孔 /
- 氟掺杂 /
- 气体吸附 /
- 染料吸附 /
- 二茂铁
Abstract: Conjugated microporous polymers (CMPs) have attracted extensive attention due to their stable pore structure, various synthesis methods and applications in gas adsorption and dye adsorption in wastewater treatment. Based on the Sonogashira coupling reaction, two fluorine-doped porous polymers (synthetic route of ferrocene (Fc)-1,3,5-trifluoro-2,4,6-triethynylbenzene (FAB)-CMP, Fc-5,10,15,20-tetrakis(2-fluoro-4-ethynylphenyl) porphyrin (TFPP)-CMP) were designed and synthesized by using FAB and TFPP as the center construction units, 1,1'-dibromoferrocene (Fc(Br)₂) as a linking unit. The chemical structure, thermal stability, elemental composition and particle morphology of CMPs were investigated in detail. The results show that the fluorine-doped porous polymer is successfully synthesised by the Sonogashira coupling reaction, and the product exhibits good thermal stabi-lity and stable porosity. The BET specific surface areas of Fc-FAB-CMP and Fc-TFPP-CMP are 302.89 m²/g and 125.2 m²/g, respectively. Moreover, the introduction of ferrocene and fluorine can be the adsorption site of cationic dye methyl violet (MV), the highest adsorption value of Fc-FAB-CMP for MV reaches 318 mg/g.
- porous /
- fluorine-doped /
- gas adsorption /
- dye adsorption /
- ferrocene

HTML全文

图 1 氟掺杂多孔聚合物二茂铁基(Fc)-1,3,5-三氟-2,4,6-三乙炔基苯(FAB)-共轭微孔聚合物(CMP)和Fc-5,10,15,20-四(2-氟-4-乙炔基苯基)卟啉(TFPP)-CMP制备路线图

Figure 1. Synthetic routes of ferrocene (Fc)-1,3,5-trifluoro-2,4,6-triethynylbenzene (FAB)-conjugated microporous polymers (CMP) and Fc-5,10,15,20-tetrakis(2-fluoro-4-ethynylphenyl) porphyrin (TFPP)-CMP

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图 2 Fc-FAB-CMP和Fc-TFPP-CMP的FTIR图谱

Figure 2. FTIR spectra of Fc-FAB-CMP and Fc-TFPP-CMP

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图 3 Fc-FAB-CMP (a) 和Fc-TFPP-CMP (b) 的XPS图谱

Figure 3. XPS spectra of Fc-FAB-CMP (a) and Fc-TFPP-CMP (b)

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图 4 Fc-FAB-CMP和Fc-TFPP-CMP的热重曲线(a)和XRD图谱(b)

Figure 4. TGA curves (a) and XRD patterns (b) of Fc-FAB-CMP and Fc-TFPP-CMP

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图 5 Fc-FAB-CMP的SEM图像 (a) 和TEM图像 (c)；Fc-TFPP-CMP的SEM图像 (b) 与TEM图像 (d)

Figure 5. SEM (a) and TEM (c) images of Fc-FAB-CMP; SEM (b) and TEM (d) images of Fc-TFPP-CMP

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图 6 Fc-FAB-CMP和Fc-TFPP-CMP的N₂吸脱附曲线 (a) 和孔径分布曲线 (b)

Figure 6. N₂ adsorption-desorption isotherms (a) and pore size distribution curves (b) of Fc-FAB-CMP and Fc-TFPP-CMP

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图 7 Fc-FAB-CMP和Fc-TFPP-CMP对N₂, CH₄和CO₂的吸脱附曲线 ((a)~(d)) 及气体选择性拟合曲线 ((a')~(d'))

Figure 7. N₂, CH₄ and CO₂ isotherms ((a)-(d)) and simulated selectivity lines ((a')-(d')) of Fc-FAB-CMP and Fc-TFPP-CMP

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图 8 Fc-FAB-CMP和Fc-TFPP-CMP对气体H₂的吸附曲线 (a) 及吸附焓曲线 (b)

Figure 8. H₂ isotherms (a) and isosteric adsorption curves (b) of Fc-FAB-CMP and Fc-TFPP-CMP

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图 9 Fc-FAB-CMP和Fc-TFPP-CMP对甲基紫(MV)溶液吸附前后的紫外吸收光谱

Figure 9. UV spectra curves of methyl violet (MV) solution before and after treated by Fc-FAB-CMP and Fc-TFPP-CMP

C₀—Initial concentration; C_e—Concentration at adsorption equilibrium

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图 10 Fc-FAB-CMP和Fc-TFPP-CMP对MV溶液吸附动力学拟合曲线

Figure 10. Adsorption kinetic curves of Fc-FAB-CMP and Fc-TFPP-CMP to MV

C_t—Dye concentration at time t

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图 11 Fc-FAB-CMP和Fc-TFPP-CMP对甲基紫吸附的粒子内扩散模型

Figure 11. Intraparticle diffusion models of Fc-FAB-CMP and Fc-TFPP-CMP to MV

Q_t—Adsorption capacity at time t

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表 1 Fc-FAB-CMP和Fc-TFPP-CMP元素含量(at%)

Table 1. Element contents of Fc-FAB-CMP and Fc-TFPP-CMP (at%)

Material	C	Fe	F	N
Fc-FAB-CMP	89.66	4.26	6.08	—
Fc-TFPP-CMP	87.88	1.28	3.59	7.26

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表 2 Fc-FAB-CMP和Fc-TFPP-CMP的多孔性质

Table 2. Porosity data of Fc-FAB-CMP and Fc-TFPP-CMP

Sample	S_BET /(m²·g⁻¹)	S_micro /(m²·g⁻¹)	S_micro/S_BET	V_total /(cm³·g⁻¹)
Fc-FAB-CMP	302.9	106.8	0.35	0.27
Fc-TFPP-CMP	125.2	47.1	0.38	0.14
Notes: S_BET—Specific surface area calculated from the nitrogen adsorption isotherm using the BET method; S_micro—Micropore surface area calculated from the nitrogen adsorption isotherm using the t-plot method; V_total—Total pore volume.

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表 3 多种有机多孔材料常温、常压条件下对MV的吸附能力对比

Table 3. Comparison on adsorption capacity of organic porous materials to MV

Sample	S_BET/(m²·g⁻¹)	M_max/(mg·g⁻¹)	Reference
Fc-FAB-CMP	303	318	This work
Fc-TFPP-CMP	125	120	This work
ASRM	130	61	[43]
Cu(BDC-NH₂)(4,4’-Bipy)(0.5)	124	60	[44]
CMK-3	1568	158	[45]
Notes: M_max—Maximum adsorption of MV; ASRM—Activated sintering process red mud; Cu(BDC-NH₂)(4,4’-Bipy)(0.5)—An anionic metal-organic framework; CMK-3—A mesoporous carbon material.

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表 4 Fc-FAB-CMP和Fc-TFPP-CMP对MV的动力学参数和相关系数R²

Table 4. Kinetic parameters and correlation coefficient R² for MV of Fc-FAB-CMP and Fc-TFPP-CMP

Sample	Model	Q_e /(mg·g⁻¹)	k₁/k₂	R²
Fc-FAB-CMP	First	265.28	4.08×10⁻³	0.966
Fc-FAB-CMP	Second	393.53	7.46×10⁻⁶	0.978
Fc-TFPP-CMP	First	115.86	2.92×10⁻³	0.996
Fc-TFPP-CMP	Second	193.03	9.34×10⁻⁶	0.996
Notes: Q_e—Adsorption capacity at equilibrium; k₁ and k₂—Adsorption rate constants of the pesudo-firs model and the pesudo-second model, respectively; R²—Correlation coefficient.

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