Structure and Properties of Sulfonated Poly(ether ether ketone)/Laponite Proton Exchange Membrane for All Vanadium Redox Flow Battery †

doi:10.7503/cjcu20190190

Abstract

Abstract:

A series of sulfonated poly(ether ether ketone)/laponite(SPEEK/Lap) composite membranes was prepared by solution-casting method using SPEEK with a sulfonation degree of 58% as membrane matrix. The membrane properties such as water uptake(WU), swelling ratio(SR), proton conductivity(σ), vanadium ion permeability and ion selectivity were detailly characterized and discussed. The results show that the introduced Lap nanofillers effectively improve σ, SR and mechanical properties of SPEEK composite membranes. The tensile strength of the SPEEK/Lap-0.2 composite membrane is 1.64 times that of pure SPEEK membrane. When the mass fraction of Lap increases from 0.2% to 1.5%, σ(19.9—23.6 mS/cm) increases accordingly. The ion selectivity of SPEEK/Lap-0.2 composite membrane is the best(5.55×10 ³ S·min·cm ^-3), which is about 1.39 times that of Nafion 117 membrane(3.99 S·min·cm ^-3). In the single cell test, the self-discharge time of SPEEK/Lap-0.2 composite membrane is 57.2 h, which is 2.4 times that of Nafion 117 and 1.5 times that of pure SPEEK membrane. At a current density of 80 mA/cm ², the voltage efficiency(VE, 86.5%) and energy efficiency(EE, 84.0%) of SPEEK/Lap-0.2 composite membrane are much higher than those of Nafion 117(VE: 83.8%, EE: 80.7%) and SPEEK membrane(VE: 81.4%, EE: 78.9%). During the 100 times charge-discharge test, SPEEK/Lap-0.2 composite membrane exhibits a stable energy efficiency, proving its good structure stability. In addition, SPEEK/Lap composite membranes exhibit a higher chemical stability in harsh oxidizing environment as compared with SPEEK membrane. Laponite nanofillers demonstrate a promising application as the low-cost high proton conductor, which can be used to prepare the proton exchange membrane(PEM) with high ion selectivity and low vanadium ion permeability for vanadium redox flow battery(VRFB) application.

Key words: Proton exchange membrane, Sulfonated poly(ether ether ketone), Laponite, Vanadium redox flow battery

CLC Number:

O646
O631

TrendMD:

LIU Bo,ZOU Nan,ZHANG Yuxia,SHI Haifeng. Structure and Properties of Sulfonated Poly(ether ether ketone)/Laponite Proton Exchange Membrane for All Vanadium Redox Flow Battery ^†[J]. Chem. J. Chinese Universities, 2019, 40(10): 2186.

Figures/Tables 10

Fig.1 FTIR spectra of SPEEK(a), SPEEK/Lap-0.2(b), SPEEK/Lap-0.5(c), SPEEK/Lap-1(d), SPEEK/Lap-1.5(e) membranes

Fig.2 Cross-section SEM images(A1—D1) and the relevant EDX element mapping of Mg(A2—D2) and Si(A3—D3) of composite membrans SPEEK/Lap-0.2(A1—A3), SPEEK/Lap-0.5(B1—B3), SPEEK/Lap-1(C1—C3) and SPEEK/Lap-1.5(D1—D3)

Sample	Thickness/ μm	IEC/ (mmol·g^-1)	WU(%)	SR_in-plane(%)	SR_{through-plane}(%)	σ/ (mS·cm^-1)	Tensile strength/ MPa	Tensile modulus/ GPa
Nafion 117	186±1	0.88±0.01	21.1±0.3	28.9±0.4	23.5±0.2	26.8±0.3	19.4±0.3	0.11±0.03
SPEEK	81±1	1.74±0.01	39.9±0.4	15.6±0.2	14.7±0.1	18.6±0.3	37.4±0.3	0.90±0.05
SPEEK/Lap-0.2	80±1	1.74±0.01	39.6±0.3	11.1±0.1	8.6±0.1	19.9±0.2	61.4±0.3	1.26±0.07
SPEEK/Lap-0.5	81±1	1.75±0.01	39.7±0.2	12.0±0.1	9.8±0.1	20.6±0.3	62.0±0.4	1.25±0.07
SPEEK/Lap-1.0	82±1	1.81±0.01	41.3±0.3	12.2±0.1	10.9±0.1	22.8±0.4	66.3±0.4	1.62±0.05
SPEEK/Lap-1.5	81±1	1.87±0.01	43.8±0.4	13.4±0.2	12.6±0.1	23.6±0.4	68.5±0.4	1.75±0.07

Fig.3 Vanadium ion permeability(A) and ion selectivity(B) of SPEEK/Lap-x and Nafion 117 membranes a. Nafion117; b. SPEEK; c. SPEEK/Lap-0.2; d. SPEEK/Lap-0.5; e. SPEEK/Lap-1.0; f. SPEEK/Lap-1.5.

Fig.4 VRFB efficiency of Nafion 117(a), SPEEK(b) and SPEEK/Lap-0.2(c) at current density of 80 mA/cm2

Fig.5 Self-discharge curves of Nafion 117(a), SPEEK(b) and SPEEK/Lap-0.2(c) membranes

Membrane	Current density/(mA·cm^-2)	VE(%)	EE(%)	Ref.
SPEEK/Lap-0.2	80	86.5	84	This work
SPEEK/g-C₃N₄-1.5	30	85.7	83.6	[16]
SPEEK/SGO-3	30	84.8	81.1	[19]
SPEEK/PPD-GO-1	30	85.4	82.5	[24]
SPEEK/PAN-20	80	86.8	83.5	[30]

Fig.6 Cycling efficiencies of Nafion 117 and SPEEK/Lap-0.2 membranes at 50 mA/cm2 during 100 charge-discharge cycles

Fig.7 Charge capacity retention of Nafion 117(a) and SPEEK/Lap-0.2(b) membrane at 50 mA/cm2 during 100 charge-discharge cycles

Membrane	Mass loss(%)	Reductionrate rate of V $O 2 +$ to VO²⁺(%)	Decreased tensile strength(%)
Nafion 117	1.1	1.6	12.1
SPEEK	3.5	4.3	22.4
SPEEK/Lap-0.2	1.7	3.3	15.3
SPEEK/Lap-1.5	1.3	3.0	13.5

Membrane	Mass loss(%)	Reductionrate rate of V $O 2 +$ to VO²⁺(%)	Decreased tensile strength(%)
Nafion 117	1.1	1.6	12.1
SPEEK	3.5	4.3	22.4
SPEEK/Lap-0.2	1.7	3.3	15.3
SPEEK/Lap-1.5	1.3	3.0	13.5

References 31

[1]	Yang Z. G., Zhang J. L., Kintner-Meyer M. C., Lu X. C., Choi D. W., Lemmon J. P., Liu J. , Chem. Rev., 2011,111(5), 3577— 3613
[2]	Wang W., Luo Q. T., Li B., Wei X. L., Li L. Y., Yang Z. G. , Adv. Funct. Mater., 2013,23(8), 970— 986
[3]	Lee K. J., Chu Y. H., , Vacuum, 2014,107(3), 269— 276
[4]	Xi J. Y., Wu Z. H., Qiu X. P., Chen L. Q. , J. Power Sources, 2007,166(2), 531— 536
[5]	Schwenzer B., Zhang J. L., Kim S., Li L. Y., Liu J., Yang Z. G. , ChemSusChem, 2011,4(10), 1388— 1406
[6]	Cao L., Kong L., Kong L. Q., Zhang X. X., Shi H. F. , J. Power Sources, 2015,299, 255— 264
[7]	Cao L., Sun Q. Q., Gao Y. H., Liu L. T., Shi H. F. , Electrochim. Acta, 2015,158, 24— 34
[8]	Kim S., Tighe T. B., Schwenzer B., Yan J. L., Zhang J. L. Liu J., Yang Z. G., Hickner M. A. , J. Appl. Electrochem., 2011,41(10), 1201— 1213
[9]	Kim S., Yan J. L., Schwenzer B., Zhang J. L., Li L., Liu J., Yang Z. G., Hickner M. A. , Electrochem. Commun., 2010,12(11), 1650— 1653
[10]	Xi J. Y., Li Z. H., Yu L. H., Yin B. B., Wang L., Liu L., Qiu X. P., Chen L. Q. , J. Power Sources, 2015,285, 195— 204
[11]	Jia C. K., Cheng Y. H., Ling X., Wei G. J., Liu J. G., Yan C. W. , Electrochim. Acta, 2015,153, 44— 48
[12]	Zhu X. Y., Qian H. D., Jiang J. J., Yue Z. Y. , Chem. J. Chinese Universities, 2018,39(9), 2046— 2053
	( 朱星烨, 钱汇东, 蒋晶晶, 乐舟莹 , 高等学校化学学报, 2018,39(9), 2046— 2053)
[13]	Chen Y. H., Huang X. H. , Chem. J. Chinese Universities, 2019,40(2), 410— 418
	( 陈宇涵, 黄雪红 . 高等学校化学学报, 2019,40(2), 410— 418)
[14]	Li Z. H., Dai W. J., Yu L. H., Xi J. Y. Qiu X. P., Chen L. Q. , J. Power Sources, 2014,257(3), 221— 229
[15]	Zhang Y. X., Wang H. X., Yu W. K., Shi J. L. Shi H. F. , J. Membr. Sci., 2018,564, 916— 925
[16]	Niu R. T., Kong L. Q., Zheng L. Y., Wang H. X., Shi H. F. , J. Membr. Sci., 2017,525, 220— 228
[17]	Ji Y., Tay Z. Y., Li S. F. Y. , J. Membr. Sci., 2017,539, 197— 205
[18]	Yu L. W., Mu D., Liu L., Xi J. Y. , J. Membr. Sci., 2018,564, 237— 246
[19]	Zheng L. Y., Wang H. X., Niu R. T., Zhang Y. X., Shi H. F. , Electrochim. Acta, 2018,282, 437— 447
[20]	Plackett D., Siu A., Li Q. F., Pan C., Jensen J. O., Nielsen S. F., Permyakova A. A., Bjerrum N. J. , J. Membr. Sci., 2011,383(1/2), 78— 87
[21]	Negrete-Herrera N., Putaux J. L., Bourgeat-Lami E, , Prog. Solid State Chem., 2006,34(2—4), 121— 137
[22]	Aziz M. A., Shanmugam S. , J. Mater. Chem. A, 2017,5(32), 16663— 16671
[23]	Dai W. J., Shen Y., Li Z. H., Yu L. H., Xi J. Y., Qiu X. P. , J. Mater. Chem. A, 2014,2(31), 12423— 12432
[24]	Kong L. Q., Zheng L. Y., Niu R. T., Wang H. X. Shi H. F. , RSC Adv., 2016,6(102), 100262— 100270
[25]	Zhang H. Q., Yan X. M., Gao L., Hu L., Ruan X. H., Zheng W. J., He G. H. , ACS Appl. Mater. Inter., 2019,11(5), 5003— 5014
[26]	Li Y. X., Liang L., Liu C. P., Li Y., Xing W., Sun J. Q. , Adv. Mater., 2018,30(25), e1707146
[27]	Yu L. H., Lin F., Xiao W. D., Luo D. W., Xi J. Y. , J. Membr. Sci., 2018,549, 411— 419
[28]	Kreuer K. D., Paddison S. J., Spohr E., Schuster M. , Chem. Rev., 2004,104, 4637— 4678
[29]	Karthikeyan C. S., Nunes S. P., Prado L. A. S. A., Ponce M. L., Silva H., Ruffmann B., Schulte K. , J. Membr. Sci., 2005,254(1/2), 139— 146
[30]	Li Z. H., Dai W. J., Yu L. H., Liu L., Xi J. Y., Qiu X. P., Chen L. Q. , ACS Appl. Mater. Inter., 2014,6(21), 18885— 18893
[31]	Yuan Z. Z., Li X. F., Hu J. B., Xu W. X., Cao J. Y., Zhang H. M. , Phys. Chem. Chem. Phys., 2014,16(37), 19841— 19847