Nano Energy
·
2022
·
IF 19.069
Sijing Liu,Yuewang Yang,Shusheng Chen,Jiongzhi Zheng,Dong Gyu Lee,Dan Li,Jinglei Yang,Baoling Huang
Flexible ionic thermoelectric materials with large thermopowers show great promise for ultrasensitive thermal detection in wearable devices . Here large and tunable p- and n-type thermopowers are reported in stretchable and self-healing ionogels made of a fluorocarbon elastomer poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), an ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIMTFSI) and a salt acting as the thermopower regulator. Particularly, a self-healing n-type ionic thermoelectric material is developed for the first time. The thermopower of the resultant ionogels varies from + 30 mV K −1 to − 21 mV K −1 at 90% relative humidity. Meanwhile, the ionogels exhibit excellent stretchability up to 1700% and appropriate Young’s modulus of around 0.26 MPa. Both the mechanical and thermoelectric properties can self-heal spontaneously after damage. Taking advantage of the large p and n-type thermopowers, the stretchable self-healing ionogels are integrated as a flexible thermoelectric detector with 10 pairs of p- and n-type legs on copper electrodes, showing a total thermopower of 0.25 V K −1 operating with a low temperature difference of 1–2 K.
研究领域:
材料科学
·
柔性电子
·
热电技术
✓ 已验证
产品关联
DOI
高影响因子
APPLIED THERMAL ENGINEERING
·
2021
·
IF 5.295
Jincheng Tang,Yongqi Xie,Shinan Chang,Zhenrong Yan,Hongwei Wu,Hongxing Zhang
Phase change material (PCM) has great potential in thermal control of aircraft electronic components because of their excellent latent heat capacity. In the current work, a finned copper foam phase change energy storage unit (PCESU) was fabricated using n-eicosane, 97.2% porosity copper foam and 0.8 mm fins. The effects of four different heating power i.e. 40 W, 45 W, 50 W, 55 W corresponding to heat flux of 0.4 W/cm 2 , 0.45 W/cm 2 , 0.5 W/cm 2 , 0.55 W/cm 2 at four different centrifugal acceleration magnitudes, i.e. 0 g, 5 g, 9 g, 13 g with three different acceleration directions on the thermal performance of PCESU were experimentally studied in a systematic manner. Experimental results indicated that: (1) the acceleration direction has a significant effect on the thermal performance of PCESU which can be improved for the cases of vertical and opposite directions, whereas restrained for the case of same direction. Under acceleration condition, the average melting time for the cases of opposite and same direction are 15.19% and 37.10% longer than that for the case of vertical direction, respectively. The temperature difference of PCESU while the melting is completed is 95.12% higher than that for the case of vertical direction on average. (2) the effect of acceleration magnitude on the heat transfer performance can be determined significantly when the acceleration direction is applied. The melting time decreases with the increase of the acceleration magnitude along vertical direction and increases along same direction. The temperature difference decreases with the increase of the acceleration magnitude along vertical direction, whereas increases along opposite or same direction. Moreover, the melting time and temperature difference for acceleration magnitude changing from 0 g to 5 g have an obvious larger change rate than that from 5 g to 9 g and 9 g to13 g. (3) the melting time is negatively correlated to the heating power, whereas the temperature difference is positively correlated to the heating power. The proposed two-dimensional (2D) simplified model can be helpful to reveal the physical mechanism of the thermal performance of PCESU.
研究领域:
热力学
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航空航天工程
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材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Shouze Li,Zhou Li,Dongyan Xu,Run Hu
Emerging thermocells exhibit a significant potential in low-grade heat harvesting owe to their high mV-scale thermopower, low cost, and high robustness. Fundamentally, three effects contribute to the thermopower enhancement of liquid thermocells, i.e. original concentration effect, solvation effect, and normalized concentration gradient effect. Yet, the contribution of the solvation effects and the normalized concentration gradient in organic solvents remains a subject of debate. In this paper, we integrate experiments, spectral analysis, and electrochemical theory to demonstrate that the normalized concentration gradient dominates the enhancement of thermopower in the investigated organic solvents, whereas the solvation effect is weak. Further, the introduction of ethanol results in a thermosensitive solubility of K 4 Fe(CN) 6 and a minimal concentration at the cold end, which establishes a huge substantial normalized Fe(CN) 6 4- concentration gradient and increases the Seebeck coefficient to 3.4 mV/K. Simultaneously, the precipitation resulting from the introduction of an organic solvent notably diminishes the heat convection within the system. As a result, the optimized TC-35EtOH system yields a ZT value (0.094) and Carnot-relative efficiency (2.52 %) that are 7 times greater than those of its initial counterpart. Additionally, the system’s high power density of 3.64 W/m 2 suggests its potential for harnessing low-grade heat waste energy.
研究领域:
物理化学
·
能源材料科学
✓ 已验证
DOI
高影响因子
eScience
·
2023
·
IF 0
Qikai Li,Cheng-Gong Han,Shuaihua Wang,Cai-Chao Ye,Xinbo Zhang,Xiao Ma,Tao Feng,Yuchen Li,Weishu Liu
Ionic thermoelectric (i-TE) technologies can power Internet of Things (IoT) sensors by harvesting thermal energy from the environment because of their large thermopowers. Present research focuses mostly on using the interactions between ions and matrices to enhance i-TE performance, but i-TE materials can benefit from utilizing different methods to control ion transport. Here, we introduced a new strategy that employs an ion entanglement effect. A giant thermopower of 28 mV K −1 was obtained in a quasi-solid-state i-TE Gelatin-CF 3 SO 3 K–CH 3 SO 3 K gel via entanglement between C F 3 S O 3 − and C H 3 S O 3 − anions. The anionic entanglement effect involves complex interactions between these two anions, slowing anionic thermodiffusion and thus suppressing bipolar effects and boosting p-type thermopower. A Au@Cu | Gelatin-CF 3 SO 3 K–CH 3 SO 3 K | Au@Cu i-TE device with a generator mode delivers a specific output energy density of 67.2 mJ m −2 K −2 during 2 h of discharging. Long-term operation of the i-TE generator for 10 days shows that the harvested energy density offers an average of 2 J m −2 per day in a cyclic working-reactivation model at a temperature difference of 6 K. The results demonstrate that anionic entanglement is an effective strategy for achieving giant thermopower with i-TE gels, so they have excellent potential for powering IoT sensors.
研究领域:
材料科学
·
能源技术
✓ 已验证
DOI
ADVANCED FUNCTIONAL MATERIALS
·
2023
·Vol. 33
·期 49
·2305835
·
IF 19
Qikai Li,Dangkai Yu,Shuaihua Wang,Xinbo Zhang,Yuchen Li,Shien-Ping Feng,Weishu Liu
Ionic thermoelectric (i-TE) gels can have a high thermopower, if the thermodiffusion of mobile cation/anion is decoupled, attracting increasing attentions. Herein, it is shown a high p-type i-TE thermopower of 41.8 mV K −1 in agarose-based ionic thermoelectric gels of AG- x Na:DBS (AG: agarose, Na:DBS: sodium dodecyl benzene sulfonate). The exclusively high thermopower is relative to the successfully decoupling the thermodiffusion of cation Na + and anion DBS − . A unique porous structure is formed due to the micellization of the amphiphilic DBS − with the hydrophilic benzenesulfonic group attached to the hydrous agarose gel chains, while the hydrophobic alkyl chain point to the pore centers. As a result, the DBS − micelles are almost immobile as compared with Na + , which can be reconsidered as a part of the gel matrix. The work shines a light on decoupling of cation/anion thermodiffusion through tailoring the microstructure of the quasi-solid i-TE materials.
研究领域:
材料科学
·
物理化学
✓ 已验证
DOI
高影响因子
Materials Reports: Energy
·
2025
·
IF 13.8
Wei Fang,Zeping Ou,Yifan Wang,Xiaoxue Lin,Hao Yang,Yujie Zheng,Jing Li,Lei Wang,Lijun Hu,Chen Li,Jianyong Ouyang,Kuan Sun
Thermocells are attracting growing interest as a promising thermoelectric technology for low-grade heat harvesting. However, the scarcity of high-performance redox couples featuring intrinsically high thermopower ( S e ) and fast redox kinetics hinders thermocells rapid development. Identifying potential intrinsically high-performance redox couples remains a significant challenge. This work introduces a novel n-type copper (Ⅰ/Ⅱ) chloride (CuCl/CuCl 2 ) redox couple with intrinsically high performance. Through tailored electrolyte design, long-term stability was significantly improved by reducing proton concentration to suppress cuprous ion photo-oxidation, while ammonium chloride solvation enhanced cuprous ion solubility. The resulting system achieves a S e value closely aligned with theoretical predictions and exhibits rapid redox kinetics. Consequently, the optimized CuCl/CuCl 2 intrinsic system demonstrated a high S e of 1.52 mV K ‒1 and a record-high normalized power density P max (Δ T ) ‒2 of 0.399 mW m ‒2 K ‒2 , surpassing previously reported intrinsic n-type thermocells and rivaling the performance of p-type pristine 0.4 M ferri/ferrocyanide systems. A prototype module comprising 30 p-n units successfully powered a line of light-emitting diodes or a thermohygrometer. This work introduces a valuable redox couple for further advancing high-performance thermocells and demonstrates a viable strategy for developing novel redox systems.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2025
·
IF 9.5
Zizheng Xiong,Weiguo Wang,Zhengzhong Wu,Zexi Zhao,Qingtao Zeng,Hongqiang Li,Xingrong Zeng,Bowei Wu,Xuejun Lai
High thermopower and fire-safety ionic thermoelectric hydrogel is crucial for the development of new energy storage device but full of challenges. Herein, a high-thermopower and flame-retardant ionic hydrogel (HIG) with high ion selectivity was prepared via thermally initiated free-radical polymerization. It was found that the thermoelectric type of HIG transitioned from negative (n-type) to positive (p-type) as the sodium chloride content increased from 0.67 wt% to 1.00 wt%. Afterwards, the ionic thermoelectric pair (p-n junction) with superior thermoelectric performance was constructed. The Seebeck coefficients of n-HIG and p-HIG reached -1.95 mV·K-1 and 2.14 mV·K-1, respectively, while the p-n junction exhibited a much higher Seebeck coefficient of 3.74 mV·K-1. When being burned, HIG rapidly generated a voltage exceeding 50 mV, and triggered a fire alarm within 4 s, demonstrating excellent thermoelectric efficiency and sensitive early fire-warning capability. Besides, HIG exhibited excellent flame retardancy. Even a propane torch could not ignite HIG within 20 s. The limiting oxygen index (LOI) of wood coated with HIG (Wood@HIG) was higher than 90%, making it rapidly self-extinguishing. Notably, HIG also demonstrated good electrochemical performance and remarkable thermal charging energy storage capabilities, showing good potential for applications in supercapacitors.
研究领域:
材料科学
·
储能
·
热电材料
·
消防安全工程
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）