PEDOT∶PSS及其纳米复合材料热电性质的研究进展

鲍程鹏; 周亚杰; 董岚; 吴子华; 李奕怀; 谢华清; 王元元

doi:10.13801/j.cnki.fhclxb.20220505.001

PEDOT∶PSS及其纳米复合材料热电性质的研究进展

doi: 10.13801/j.cnki.fhclxb.20220505.001

鲍程鹏¹,
周亚杰¹,
董岚^{1, 2},
吴子华^{1, 2},
李奕怀^{1, 2},
谢华清¹,
王元元^{1, 2, ,}

1.
上海第二工业大学　能源与材料学院，上海 201209
2.
上海先进热功能材料工程技术研究中心，上海 201209

基金项目: 国家自然科学基金(51876111；52176081)；上海市自然科学基金(21ZR1424500)；上海市“曙光”项目(18SG54)；上海市科委地方能力建设项目(22010500700)National Natural Science Foundation of China (51876111; 52176081); National Natural Science Foundation of Shanghai (21ZR1424500); “Shuguang Program”Supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission (18SG54); Local Capacity Building Project of Shanghai Science and Technology Commission (22010500700)

详细信息

通讯作者:
王元元，博士，教授，硕士生导师，研究方向为新能源材料与器件　E-mail: wangyuanyuan@sspu.edu.cn

中图分类号: TK11+5
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出版历程
- 收稿日期: 2022-03-10
- 修回日期: 2022-04-19
- 录用日期: 2022-04-23
- 网络出版日期: 2022-05-05
- 刊出日期: 2023-02-15

Research progress in thermoelectric properties of PEDOT∶PSS and its nanocomposites

BAO Chengpeng¹,
ZHOU Yajie¹,
DONG Lan^{1, 2},
WU Zihua^{1, 2},
LI Yihuai^{1, 2},
XIE Huaqing¹,
WANG Yuanyuan^{1, 2
, ,}

1.
School of Energy and Materials, Shanghai Polytechnic University, Shanghai 201209, China
2.
Shanghai Engineering Research Center of Advanced Thermal Functional Materials, Shanghai 201209, China

摘要

摘要: 近年来，随着能源危机的加剧，可以将热能与电能进行直接转换的热电材料得到了广泛的关注。在众多热电材料体系中，有机无机纳米复合热电材料具有独特优势。相比于无机材料，有机材料成本低、质量轻、机械柔韧性好、热导率较低。添加不同类型的添加材料构成纳米复合材料后，额外引入的声子-界面散射能进一步降低热导率，同时有机无机材料能带不匹配引起的载流子筛选效应进一步提升塞贝克(Seebeck)系数。因此，目前大量工作证明有机无机纳米复合热电材料有潜力获得高的热电优值(Figure of merit，ZT)，在微型热电制冷器件、柔性可穿戴发电设备、温度传感器等领域均具有光明的应用前景。本文聚焦聚(3, 4-乙烯二氧噻吩)∶聚(苯乙烯磺酸盐)(PEDOT∶PSS)热电材料及以其为基底构成的纳米复合材料热电性能的研究工作，综述了提升PEDOT∶PSS热电性能的物理方法、化学试剂改性法等。进一步重点讨论了加入不同类型的无机填料的PEDOT∶PSS基纳米复合材料热电性质的研究进展，并揭示了其热电性能提升的内在机制。
- PEDOT∶PSS /
- 有机热电材料 /
- 有机无机纳米复合材料 /
- 热电优值 /
- 功率因子
Abstract: In recent years, with the aggravation of energy crisis, thermoelectric materials which can directly convert heat energy to electric energy have attracted much attention. Among many types of thermoelectric materials, organic-inorganic hybrid nanocomposites have unique advantages. Compared with inorganic materials, organic materials have the advantages of low cost, light weight, good mechanical flexibility and low thermal conductivity. Once different types of addictions are introduced to form nanocomposites, additional phonon-interface scattering can further reduce the thermal conductivity. Moreover, carrier filtering effect induced by band mismatch between organic and inorganic materials enhances Seebeck coefficient. Therefore, abundance works have proved that organic-inorganic hybrid nanocomposites have the potential to obtain promoted thermoelectric figure of merit (ZT), and have bright application prospects in micro-thermoelectric refrigeration devices, flexible wearable power generation devices, temperature sensors and other fields. This paper focuses on the thermoelectric properties of poly(3, 4-ethylenedioxythiophene)∶poly(styrene sulfonate) (PEDOT∶PSS) thermoelectric materials and its nanocomposites. The physical methods and chemical reagent modification methods to improve the thermoelectric properties of PEDOT∶PSS are reviewed. The research progress of the thermoelectric properties of PEDOT∶PSS based nanocomposites with different types of inorganic fillers is further discussed. The inherent mechanisms of the improvement of thermoelectric properties of PEDOT∶PSS based nanocomposites are also revealed in detail.
- PEDOT∶PSS /
- organic thermoelectric materials /
- organic-inorganic hybrid nanocomposites /
- figure of merit /
- power factor

HTML全文

图 1 (a) 聚(3, 4-乙烯二氧噻吩)∶聚(苯乙烯磺酸盐)(PEDOT∶PSS)化学式；(b) PEDOT∶PSS电阻率随温度变化的性质^[22]；(c) 乙二醇(EG)处理的PEDOT∶PSS随时间变化的热电(TE)性能^[28]；(d) 用不同浓度的甲酸处理的PEDOT∶PSS薄膜的平均电导率^[33]

Figure 1. (a) Chemical formula of poly(3, 4-ethylenedioxythiophene)∶poly(styrene sulfonate) (PEDOT∶PSS); (b) Dependence of electrical resistivity of PEDOT∶PSS on temperature^[22]; (c) Thermoelectric (TE) performance of PEDOT∶PSS processed by ethylene glycol (EG) over time^[28]; (d) Average conductivity of PEDOT∶PSS films treated with different concentrations of formic acid^[33]

DMSO—Dimethyl sulfoxide

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图 2 不同有机溶剂改性的PEDOT∶PSS薄膜的电导率(a)和塞贝克系数(b)随温度变化的性质^[25]

DMF—N, N-dimethyl formamide; THF—Tetrahydrofuran

Figure 2. Temperature dependences of the electrical conductivity (a) and Seebeck coefficient (b) of PEDOT∶PSS film prepared by modification with different organic solvents^[25]

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图 3 EG处理前后PEDOT∶PSS的形态变化示意图^[43]

Figure 3. Schematic diagram of morphological changes in the PEDOT∶PSS film before and after EG treatment^[43]

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图 4 NaOH水溶液处理SWCNTs/PEDOT∶PSS的形态变化示意图及其功率因数随NaOH浓度变化图^[44]

SWCNTs—Single-walled carbon nanotubes

Figure 4. Schematic diagram of morphology change of SWCNTs/PEDOT∶PSS treated with NaOH aqueoussolution and its power factor change with NaOH concentration^[44]

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图 5 纯PEDOT∶PSS薄膜和PEDOT∶PSS/MWCNTs复合薄膜的FTIR图谱^[47]

PXCY—Content of PSS is X mg and MWCNTs is Y mg

Figure 5. FTIR spectra of pure PEDOT∶PSS and nanocomposites composed of PEDOT∶PSS/MWCNTs^[47]

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图 6 PEDOT∶PSS/Bi₂Te₃-NWs复合材料制备过程示意图^[59]

NWs—Nanowires; h-AB—As-prepared sample was designed as h-AB with varied Bi₂Te₃-NWs contents of 5wt%, 10wt%, 25wt%, 50wt%, and 60wt% in the dried composite; p-AB—Same amount PEDOT∶PSS were drop-cast upon the other surface of Bi₂Te₃-NWs pellet

Figure 6. Schematic illustration of preparation process of PEDOT∶PSS/Bi₂Te₃-NWs composites^[59]

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图 7 不同BST NSs含量的Bi₂Te₃基于镍合金纳米片/PEDOT∶PSS复合膜的载体浓度和迁移率(插图显示了复合膜中的能量滤波效果)^[60]

BST NSs−Bi₂Te₃ based alloy nanosheet; E_F—Fermi level; ΔE—Electrical conductivity with carrier concentration

Figure 7. Carrier concentration and mobility as a function of the content of BST NSs of the drop cast BST NSs/PEDOT∶PSS composite films (Inset shows the illustration of the energy filtering effect in the composite films)^[60]

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图 8 Bi₂Te₃质子辐射的示意图和Bi₂Te₃/PEDOT∶PSS复合薄膜的合成(a)及其TEM图像(b)和HRTEM图像((c)~(e))(分别对应图(b)虚线的区域I、II和III)^[62]

Figure 8. A schematic showing the proton irradiation of Bi₂Te₃ and the synthesis of Bi₂Te₃/PEDOT∶PSS composite thin films (a) and TEM image (b) and HRTEM images ((c)-(e)) (From the regions I, II and III marked in dashed squares, respectively)^[62]

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图 9 复合薄膜内部结构^[64]

μ—Carrier mobility; σ—Conductivity

Figure 9. Internal structure of composite film^[64]

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图 10 未镀铜离子(a)和镀铜离子(b)的Bi_0.5Sb_1.5Te₃示意图^[65]

BST—Bi_0.5Sb_1.5Te₃

Figure 10. Schematic diagram of Bi_0.5Sb_1.5Te₃uncoated (a) and copper-coated (b)^[65]

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图 11 不同计量Ag_xTe的XRD图谱和晶体结构图^[68]

Figure 11. XRD patterns and crystal structure of Ag_xTe at different measurements^[68]

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图 12 利用Cu-Bi_0.5Sb_1.5Te₃/PEDOT∶PSS复合薄膜自制的热电器件^[65]

Figure 12. A thermoelectric device fabricated using Cu-Bi_0.5Sb_1.5Te₃/PEDOT∶PSS composite film^[65]

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表 1 试剂改性PEDOT∶PSS

Table 1. Reagent modification of PEDOT∶PSS

Treatment method	Conductivity/ (S·cm^–1)	Seebeck coefficient/ (μV·K^–1)	Power factor PF/ (μW·(m·K²)^–1)	ZT	Ref.
No processing	0.21	15.4	5×10⁻³	—	[37]
Apply alternating current	1373	16.5	38.6	—	[24]
DMSO	80	—	—	—	[25]
DMSO, EG	—	—	—	1.75×10⁻³	[26]
DMSO, EG	300	—	—	1.07×10⁻²	[27]
DMSO, EG	—	—	—	0.42(DMSO) 0.28(EG)	[28]
DMSO, PEO	1677	38.4±7.1	157.35	—	[29]
DMF, ZnCl₂	1400	26.1	98.2	0.125	[30]
H₂SO₄(pre-process)	100	—	—	—	[31]
H₂SO₄(post-process)	4380	—	—	—	[36]
HCOOH	2050	—	—	—	[33]
HCOOH	1900	20.6	80.6	0.32	[34]
H₂C₂O₄	800	—	—	—	[35]
H₂SO₄, NaOH	2170	39.2	334	0.29-0.49	[37]
Thionyl chloride	—	—	115.9	—	[82]
IL	—	—	46.7	—	[83]
IL(X-ray)	1163	38.8	175	—	[84]
Notes: PEO—Polyethylene oxide; IL—Ionic liquid.

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表 2 碳基材料复合PEDOT∶PSS

Table 2. Nanocomposites with PEDOT∶PSS matrix and carbon material additions

Additive material	Treatment method	Conductivity/ (S·cm^–1)	Seebeck coefficient/ (μV·K^–1)	PF/ (μW·(m·K²)^–1)	ZT	Ref.
SWCNTs	—	—	—	15.8	—	[39]
SWCNTs	—	3085.4	26.95	224	—	[40]
SWCNTs	H₂SO₄	2667.65	—	45.72	—	[41]
SWCNTs	DMSO	745.4	37.9	108.7	—	[42]
CNT	EG	831	47	185	—	[43]
SWCNTs	NaOH	1701	55.6	526	0.39	[44]
SWCNTs	Ion-exchange effect	1602.6	33.4	182.7	—	[46]
SWCNTs	IL	1732	21.9	65.7	—	[85]
GODs/SWCNTs	—	1036	13.8	19.9	0.00322	[86]
C-dots	H₂SO₄	1753.92	—	148.27	—	[48]
rGO	Bar-coating	230	—	—	—	[49]
GO	Hydrazine hydrate	30.2	519	47.4	0.084	[51]
Notes: CNT—Carbon nano tube; GOD—Graphene quantum dot; C-dots—Carbon quantum dots; rGO—Reduced graphene oxide; GO—Graphite oxide.

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表 3 PEDOT∶PSS与半导体TE材料复合提升热电性能

Table 3. PEDOT∶PSS composite with semiconductor TE material to improve thermoelectric properties

Additive material	Treatment method	Conductivity/(S·cm⁻¹)	Seebeck coefficient/ (μV·K⁻¹)	PF/ (μW·(m·K²)⁻¹)	ZT	Ref.
Bi₂Te₃nanowires	Layer-by-layer assembly	401	16.3	10.6	0.01	[59]
Bi₂Te₃	Drop casting	1295.21	—	32.26	0.05	[60]
Bi₂Te₃ nanowires	Spin coating (PSVA)	1026	47	226	—	[61]
Bi₂Te₃	Drop casting (proton irradiation)	1350	49	432	0.18±0.03	[62]
Bi_0.5Sb_1.5Te₃	Drop casting	—	—	8.3	—	[64]
Bi_0.5Sb_1.5Te₃	Drop casting (two-step reduction process)	1285	49	308	0.484	[21]
Cu-Bi_0.5Sb_1.5Te₃	Drop casting (copper plating)	2270	37.1	312	—	[65]
Ag NWs	Drop casting	84.84	18.3	28.55	2.42×10⁻³	[75]
Ag₂Te	Vacuum filtration (wet-chemical method)	397.2	75	221.7	—	[67]
Ag_xTe	Topotactic chemical transformation	—	—	72	—	[68]
Ag₂Se	Drop casting	581	51.98	178.59	—	[72]
ZnO	Spin coating	9.1	22	0.4	—	[69]
SnS	Vacuum filtration	—	19.5	27.8	—	[70]
Sb₂Te₃	Polar organic solvents aided layer-by-layer	106	42.4	19.09	0.1	[71]
Bi₂Te₃nanowires	—	—	—	7.45	0.048	[81]
Note: PSVA—Polar solvent steam annealing.

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