The existing thermoelectric materials are greatly affected by the temperature environment, which can provide better power output in a stable temperature environment by using composite phase change material with enhanced heat conduction. The graphene is dispersed in the liquid mannitol to make the nanomixed material. Test results show that the thermal conductivity of mannitol increased from 0.7 Wm^-1 K^-1 to 2.07 Wm^-1 K^-1, 179.73% times as much. The effective thermal conductivity of mannitol can be increased to 8.4236 Wm^-1 K^-1 by using a graphite foam with a porosity of 0.9. After adding 1 wt.% and 5 wt.% graphene particles, the effective thermal conductivity increased to 8.73 Wm^-1 K^-1 and 9.63 Wm^-1 K^-1, respectively. The simulation results in a large heat source environment show that mannitol with improved thermal conductivity can ensure the stable operation of the thermoelectric material in the optimal temperature environment for 120 s, and the open-circuit voltage is maintained at about 6.5 V in that time.

中文翻译：

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石墨烯纳米颗粒增强甘露醇热发电的导热系数研究

现有的热电材料受温度环境的影响很大，通过使用导热性增强的复合相变材料，可以在稳定的温度环境下提供更好的功率输出。将石墨烯分散在液体甘露醇中以制备纳米混合材料。测试结果表明，甘露醇的导热系数从0.7 Wm ^-1  K ^-1增加到2.07 Wm ^-1  K ^-1，是其的179.73％倍。使用孔隙率为0.9的石墨泡沫可以将甘露醇的有效导热系数提高到8.4236 Wm ^-1  K ^-1。添加1 wt。％和5 wt。％的石墨烯颗粒后，有效导热系数增加到8.73 Wm^-1  K ^-1和9.63 Wm ^-1  K ^-1。在大热源环境下的仿真结果表明，改善了热导率的甘露醇可以确保热电材料在最佳温度环境下稳定运行120 s，并且此时的开路电压保持在6.5 V左右。