Preparation and thermoelectric properties of phase change expanded graphite/cement composite materials
-
摘要: 热电水泥基复合材料可以将建筑物环境中的热能转化成电能，作为一种新型的能源转换途径，近年来受到了广泛关注和研究。热电水泥基复合材料在应用过程中存在最佳工作温度与环境温度不匹配的问题及热电转换效率过低，制约了热电水泥的应用。本文将熔融共混制备的膨胀石墨(EG)/石蜡(PW)相变复合材料掺入水泥基材料中，制备相变膨胀石墨/水泥复合材料。研究相变复合材料掺入量对水泥基材料热电性能的影响。相变复合材料含量的增加调节了水泥基复合材料最佳热电性能的温度区间。测试结果表明热电性能最大值对应的温度点由55℃调节至60℃和65℃，其对应的Seebeck系数分别为−24.65、−30.97和−30.90 μV/K，功率因数分别为1.39、1.57和1.67 μW·m−1·K−2；热电优值(ZT)分别为5.53×10−5、6.50×10−5和7.07×10−5。相变复合材料在相变过程中吸收热量，降低了水泥基材料的升温速率，削弱了因温度升高导致载流子浓度增加引起Seebeck系数的下降，调节了水泥基材料功率因数峰值对应的温度区间，调控了热电水泥基复合材料的使用温度范围。本文为改善热电水泥基复合材料性能提供了新的途径和方法。Abstract: Thermoelectric cement-based composite materials can convert thermal energy in building environments into electrical energy, and as a new energy conversion approach, have received widespread attention and research in recent years. There is a problem of mismatch between the optimal working temperature and environmental temperature in the application of thermoelectric cement-based composite materials, and the low thermoelectric conversion efficiency restricts the application of thermoelectric cement. This study incorporated expanded graphite (EG)/paraffin wax (PW) phase change composite materials prepared by melt blending into cement-based materials to prepare phase change expanded graphite/cement composite materials. The effect of the addition amount of phase change composites on the thermoelectric properties of cement-based materials was studied. The increase in the content of phase change composites regulates the temperature range for the optimal thermoelectric performance of cement-based composite materials. The test results show that the temperature point corresponding to the maximum thermoelectric performance is adjusted from 55℃ to 60℃ and 65℃. The corresponding Seebeck coefficient is −24.65, −30.97 and −30.90 μV/K. The power factor is 1.39, 1.57 and 1.67 μW·m−1·K−2. Thermoelectric merit (ZT) value is 5.53×10−5, 6.50×10−5 and 7.07×10−5. Phase change composites absorb heat during the phase change process, reducing the heating rate of cement-based materials, weakening the decrease in Seebeck coefficient caused by an increase in carrier concentration due to temperature rise, adjusting the temperature range corresponding to the peak power factor of cement-based materials, and regulating the temperature range of use of thermoelectric cement-based composite materials. This study provides a new approach and method for improving the performance of thermoelectric cement-based composite materials.
-
图 1 (a) 膨胀石墨(EG)/石蜡(PW)相变复合材料的制备流程；(b) 相变膨胀石墨/水泥复合材料的制备流程
Figure 1. (a) Preparation process of expanded graphite (EG)/paraffinwax (PW) phase change composites; (b) Preparation process of phase change expanded graphite/cement composite materials
PCMs—Phase change materials
图 2 水泥基复合材料Seebeck系数和电导率测试仪器原理图
Figure 2. Schematic diagram of Seebeck coefficient and conductivity testing instrument for cement-based composite materials
DC—Direct current
图 3 EG、PW和EG/PW相变复合材料的FTIR图谱
Figure 3. FTIR spectra of EG, PW and EG/PW phase change composites
图 4 EG/PW相变复合材料的SEM图像：((a), (b)) 5wt%EG/7wt%PW相变复合材料；((c), (d)) 5wt%EG/10wt%PW相变复合材料
Figure 4. SEM images of EG/PW phase change composites: ((a), (b)) 5wt%EG/7wt%PW phase change composites; ((c), (d)) 5wt%EG/10wt%PW phase change composites
图 5 PW与EG/PW相变复合材料加热前后的照片：(a) 加热前；(b) 加热后；(c) 加热后移除EG/PW相变复合材料
Figure 5. Photos of PW and EG/PW phase change composites before and after heating: (a) Before heating; (b) After heating; (c) Remove the EG/PW phase change composites after heating
图 6 相变膨胀石墨/水泥复合材料的SEM图像：((a), (b)) 15wt%EG水泥基复合材料；((c), (d)) 15wt%EG与7wt%PW水泥基复合材料；((e), (f)) 15wt%EG与10wt%PW水泥基复合材料
Figure 6. SEM images of phase change expanded graphite/cement composite materials: ((a), (b)) 15wt%EG cement-based composites; ((c), (d)) 15wt%EG and 7wt%PW cement-based composites; ((e), (f)) 15wt%EG and 10wt%PW cement-based composites
图 7 相变膨胀石墨/水泥复合材料的密度(a)和孔隙率(b)
Figure 7. Density (a) and porosity (b) of phase change expanded graphite/cement composite materials
图 8 相变膨胀石墨/水泥复合粉体粉末电导率随压强变化关系
Figure 8. Relationship between the electrical conductivity of phase change expanded graphite/cement composite powder and pressure
图 9 相变膨胀石墨/水泥复合材料的DSC曲线
Figure 9. DSC curves of phase change expanded graphite/cement composite materials
Tpeak—Temperature corresponding to peak heat absorption and heat release; ΔH—Heat absorbed or released of material per unit mass during phase transition
图 10 相变膨胀石墨/水泥复合材料热电性能随温度变化关系：(a) 冷热端温差；(b) Seebeck系数；(c) 电导率；(d) 功率因数
Figure 10. Relationship between the thermoelectric properties of phase change expanded graphite/cement composite materials and temperature: (a) Temperature difference between the cold and hot sides; (b) Seebeck coefficient; (c) Electrical conductivity; (d) Power factor
图 11 相变膨胀石墨/水泥复合材料的热导率(a)和热电优值(ZT)随温度变化关系(b)
Figure 11. Relationship of thermal conductivity (a) and thermoelectric merit (ZT) value (b) of phase change expanded graphite/cement composite materials and temperature
图 12 (a) 相变膨胀石墨/水泥复合材料热电性能调控机制；(b) 不同温度下水泥基复合材料的ZT值对比
Figure 12. (a) Mechanism of thermoelectric performance regulation of phase change expanded graphite/cement composite materials; (b) Comparison of ZT values of cement-based composites at different temperatures
Q, q—Quantity of heat; CF—Carbon fiber; CNTs—Carbon nanotubes; RGO—Reduced graphene oxide; GNP—Graphene nanosheets;
表 1 相变膨胀石墨/水泥复合材料冷端和热端的材料组成
Table 1. Material composition of cold side and hot side of phase change expanded graphite/cement composite materials
Sample Cold side Hot side Cement/g EG powder/g EG/g PW/g Cement/g EG powder/g 15wt%EG-Cement 20.0 2.0 (10wt%) 1.0 (5wt%) — 20.0 3.0 (15wt%) 15wt%EG-7wt%PW-Cement 20.0 2.0 (10wt%) 1.0 (5wt%) 1.4 (7wt%) 20.0 3.0 (15wt%) 15wt%EG-10wt%PW-Cement 20.0 2.0 (10wt%) 1.0 (5wt%) 2.0 (10wt%) 20.0 3.0 (15wt%) 
下载: 导出CSV
-
[1] SINGH V P, KUMAR M, SRIVASTAVA R S, et al. Thermoelectric energy harvesting using cement-based composites: A review[J]. Materials Today Energy,2021,21:100714. doi: 10.1016/j.mtener.2021.100714 [2] GAURAV K, PANDEY S K. Efficiency calculation of a thermoelectric generator for investigating the applicability of various thermoelectric materials[J]. Journal of Renewable and Sustainable Energy,2017,9(1):014701. doi: 10.1063/1.4976125 [3] LIU X, JANI R, ORISAKWE E, et al. State of the art in composition, fabrication, characterization, and modeling methods of cement-based thermoelectric materials for low-temperature applications[J]. Renewable & Sustainable Energy Reviews,2021,137:110361. [4] PIELICHOWSKA K, PIELICHOWSKI K. Phase change materials for thermal energy storage[J]. Progress in Materials Science,2014,65:67-123. doi: 10.1016/j.pmatsci.2014.03.005 [5] HAN G G D, LI H, GROSSMAN J C. Optically-controlled long-term storage and release of thermal energy in phase-change materials[J]. Nature Communications,2017,8:1446. doi: 10.1038/s41467-017-01608-y [6] ZHANG K, ZHANG Y, LIU J, et al. Recent advancements on thermal management and evaluation for data centers[J]. Applied Thermal Engineering,2018,142:215-231. doi: 10.1016/j.applthermaleng.2018.07.004 [7] KENISARIN M, MAHKAMOV K. Passive thermal control in residential buildings using phase change materials[J]. Renewable & Sustainable Energy Reviews,2016,55:371-398. doi: 10.1016/j.rser.2015.10.128 [8] KUZNIK F, DAVID D, JOHANNES K, et al. A review on phase change materials integrated in building walls[J]. Renewable & Sustainable Energy Reviews,2011,15(1):379-391. [9] HUA J, YUAN C, ZHAO X, et al. Structure and thermal properties of expanded graphite/paraffin composite phase change material[J]. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects,2019,41(1):86-93. doi: 10.1080/15567036.2018.1496199 [10] ANGHEL E M, GEORGIEV A, PETRESCU S, et al. Thermo-physical characterization of some paraffins used as phase change materials for thermal energy storage[J]. Journal of Thermal Analysis and Calorimetry,2014,117(2):557-566. doi: 10.1007/s10973-014-3775-6 [11] XIAO X, ZHANG P, LI M. Preparation and thermal characterization of paraffin/metal foam composite phase change material[J]. Applied Energy,2013,112:1357-1366. doi: 10.1016/j.apenergy.2013.04.050 [12] JI X, LI H, LENG C, et al. Expanded graphite/disodium hydrogen phosphate/sodium acetate trihydrate stabilized composite phase change material for heat storage[J]. Journal of Thermal Science and Technology,2016,11(2):516-534. doi: 10.1299/jtst.2016jtst0033 [13] XIA L, ZHANG P, WANG R. Preparation and thermal characterization of expanded graphite/paraffin composite phase change material[J]. Carbon,2010,48(9):2538-2548. doi: 10.1016/j.carbon.2010.03.030 [14] ZHANG Z, ZHANG N, PENG J, et al. Preparation and thermal energy storage properties of paraffin/expanded graphite composite phase change material[J]. Applied Energy,2012,91(1):426-431. doi: 10.1016/j.apenergy.2011.10.014 [15] WU S, LI T X, YAN T, et al. High performance form-stable expanded graphite/stearic acid composite phase change material for modular thermal energy storage[J]. International Journal of Heat and Mass Transfer,2016,102:733-744. doi: 10.1016/j.ijheatmasstransfer.2016.06.066 [16] MENG J, GAO D, LIU Y, et al. Heat transfer mechanism and structure design of phase change materials to improve thermoelectric device performance[J]. Energy,2022,245:123332. doi: 10.1016/j.energy.2022.123332 [17] WEI J, ZHANG Q, ZHAO L, et al. Enhanced thermoelectric properties of carbon fiber reinforced cement composites[J]. Ceramics International,2016,42(10):11568-11573. doi: 10.1016/j.ceramint.2016.04.014 [18] WEI J, NIE Z, HE G, et al. Energy harvesting from solar irradiation in cities using the thermoelectric behavior of carbon fiber reinforced cement composites[J]. RSC Advances,2014,4(89):48128-48134. doi: 10.1039/C4RA07864K [19] WEI J, FAN Y, ZHAO L, et al. Thermoelectric properties of carbon nanotube reinforced cement-based composites fabricated by compression shear[J]. Ceramics International,2018,44(6):5829-5833. doi: 10.1016/j.ceramint.2018.01.074 [20] VARELI I, TZOUNIS L, TSIRKA K, et al. High-performance cement/SWCNT thermoelectric nanocomposites and a structural thermoelectric generator device towards large-scale thermal energy harvesting[J]. Journal of Materials Chemistry C,2021,9(40):14421-14438. doi: 10.1039/D1TC03495B [21] TZOUNIS L, LIEBSCHER M, FUGE R, et al. p- and n-type thermoelectric cement composites with CVD grown p- and n-doped carbon nanotubes: Demonstration of a structural thermoelectric generator[J]. Energy and Buildings,2019,191:151-163. doi: 10.1016/j.enbuild.2019.03.027 [22] WEI J, JIA Z, WANG Y, et al. Enhanced thermoelectric performance of low carbon cement-based composites by reduced graphene oxide[J]. Energy and Buildings,2021,250:111279. doi: 10.1016/j.enbuild.2021.111279 [23] GHOSH S, HARISH S, ROCKY K A, et al. Graphene enhanced thermoelectric properties of cement based composites for building energy harvesting[J]. Energy and Buildings,2019,202:109419. doi: 10.1016/j.enbuild.2019.109419 [24] WEI J, ZHAO L, ZHANG Q, et al. Enhanced thermoelectric properties of cement-based composites with expanded graphite for climate adaptation and large-scale energy harvesting[J]. Energy and Buildings,2018,159:66-74. doi: 10.1016/j.enbuild.2017.10.032 [25] WEI J, HAO L, HE G, et al. Enhanced thermoelectric effect of carbon fiber reinforced cement composites by metallic oxide/cement interface[J]. Ceramics International,2014,40(6):8261-8263. doi: 10.1016/j.ceramint.2014.01.024 [26] JI T, ZHANG S, HE Y, et al. Enhanced thermoelectric property of cement-based materials with the synthesized MnO2/carbon fiber composite[J]. Journal of Building Engineering,2021,43:103190. doi: 10.1016/j.jobe.2021.103190 [27] GHOSH S, HARISH S, OHTAKI M, et al. Enhanced figure of merit of cement composites with graphene and ZnO nanoinclusions for efficient energy harvesting in buildings[J]. Energy,2020,198:117396. doi: 10.1016/j.energy.2020.117396 [28] WEI Y, MIAO Z, JIA Z, et al. Synergy of reduced graphene oxide and metal oxides improves the power factor of thermoelectric cement matrix composites[J]. Fullerenes Nanotubes and Carbon Nanostructures,2022,30(8):801-813. doi: 10.1080/1536383X.2021.2024167 [29] WEI J, WANG Y, LI X, et al. Dramatically improved thermoelectric properties by defect engineering in cement-based composites[J]. ACS Applied Materials & Interfaces,2021,13(3):3919-3929. [30] WEI J, ZHANG M, WANG Y, et al. Synergistic optimization of thermoelectric performance in cementitious composites by lithium carbonate and carbon nanotubes[J]. International Journal of Energy Research,2021,45(2):2460-2473. doi: 10.1002/er.5940 [31] WEI J, MIAO Z, WANG Y, et al. Boosting power factor of thermoelectric cementitious composites by a unique CNT pretreatment process with low carbon content[J]. Energy and Buildings,2022,254:111617. doi: 10.1016/j.enbuild.2021.111617 [32] JIA Z, WEI J, WANG Y, et al. Enhanced thermoelectric properties of cement-based composites by Cl2/HNO3 pretreatment of graphene[J]. Fullerenes Nanotubes and Carbon Nanostructures,2021,29(12):982-990. doi: 10.1080/1536383X.2021.1923486 [33] JAWORSKI M, BEDNARCZYK M, CZACHOR M. Experimental investigation of thermoelectric generator (TEG) with PCM module[J]. Applied Thermal Engineering,2016,96:527-533. doi: 10.1016/j.applthermaleng.2015.12.005 [34] WANG Y, DAI C, WANG S. Theoretical analysis of a thermoelectric generator using exhaust gas of vehicles as heat source[J]. Applied Energy,2013,112:1171-1180. doi: 10.1016/j.apenergy.2013.01.018 [35] ATOUEI S A, REZANIA A, RANJBAR A A, et al. Protection and thermal management of thermoelectric generator system using phase change materials: An experimental investigation[J]. Energy,2018,156:311-318. doi: 10.1016/j.energy.2018.05.109 [36] ZHOU W, LI K, ZHU J, et al. Preparation and thermal cycling of expanded graphite/adipic acid composite phase change materials[J]. Journal of Thermal Analysis and Calorimetry,2017,129(3):1639-1645. doi: 10.1007/s10973-017-6385-2 [37] LI B, LIU T, HU L, et al. Fabrication and properties of microencapsulated paraffin@SiO2 phase change compo-site for thermal energy storage[J]. ACS Sustainable Chemistry & Engineering,2013,1(3):374-380. [38] LUO D, XIANG L, SUN X, et al. Phase-change smart lines based on paraffin-expanded graphite/polypropylene hollow fiber membrane composite phase change materials for heat storage[J]. Energy,2020,197:117252. doi: 10.1016/j.energy.2020.117252 [39] 周建伟, 王储备, 禇亮亮. 石蜡/氧化石墨烯复合相变材料的制备及其热物理性能[J]. 精细石油化工, 2013, 30(2):51-54. doi: 10.3969/j.issn.1003-9384.2013.02.013ZHOU Jianwei, WANG Chubei, CHU Liangliang. Preparation and thermo-physical properties paraffin/graphene oxide composite phase-change material[J]. Speciality Petrochemicals,2013,30(2):51-54(in Chinese). doi: 10.3969/j.issn.1003-9384.2013.02.013 [40] WEI J, LI X, WANG Y, et al. Record high thermoelectric performance of expanded graphite/carbon fiber cement composites enhanced by ionic liquid 1-butyl-3-methylimidazolium bromide for building energy harvesting[J]. Journal of Materials Chemistry C,2021,9(10):3682-3691. doi: 10.1039/D0TC05595F [41] LIU X, QU M, NGUYEN A P T, et al. Characteristics of new cement-based thermoelectric composites for low-temperature applications[J]. Construction and Building Materials,2021,304:124635. doi: 10.1016/j.conbuildmat.2021.124635 [42] SINGH A P, MISHRA M, CHANDRA A, et al. Graphene oxide/ferrofluid/cement composites for electromagnetic interference shielding application[J]. Nanotechnology,2011,22(46):465701. doi: 10.1088/0957-4484/22/46/465701 [43] ISHIBE T, TOMEDA A, WATANABE K, et al. Methodology of thermoelectric power factor enhancement by controlling nanowire interface[J]. ACS Applied Materials & Interfaces,2018,10(43):37709-37716. [44] SHEN F, ZHENG Y, MIAO L, et al. Boosting high thermoelectric performance of Ni-doped Cu1.9S by significantly reducing thermal conductivity[J]. ACS Applied Materials & Interfaces,2020,12(7):8385-8391. [45] JI T, ZHANG X, ZHANG X, et al. Effect of manganese dioxide nanorods on the thermoelectric properties of cement composites[J]. Journal of Materials in Civil Engineering,2018,30(9):04018224. doi: 10.1061/(ASCE)MT.1943-5533.0002401 [46] JIANG W, XIAO J, YUAN D, et al. Design and experiment of thermoelectric asphalt pavements with power-generation and temperature-reduction functions[J]. Energy and Buildings,2018,169:39-47. doi: 10.1016/j.enbuild.2018.03.049 -
下载:
点击查看大图
计量
- 文章访问数: 795
- HTML全文浏览量: 268
- PDF下载量: 30
- 被引次数: 0
