MOE Key Laboratory of Hydraulic Machinery Transients, School of Power and Mechanical Engineering, Wuhan University, Wuhan, Hubei 430072, China.
Department of Bioengineering, University of California, Los Angeles, Los Angeles, California 90095, United States.
Nano Lett. 2020 May 13;20(5):3791-3797. doi: 10.1021/acs.nanolett.0c00800. Epub 2020 Apr 22.
Efficient heat removal and recovery are two conflicting processes that are difficult to achieve simultaneously. Here, in this work, we pave a new way to achieve this through the use of a smart thermogalvanic hydrogel film, in which the ions and water undergo two separate thermodynamic cycles: thermogalvanic reaction and water-to-vapor phase transition. When the hydrogel is attached to a heat source, it can achieve efficient evaporative cooling while simultaneously converting a portion of the waste heat into electricity. Moreover, the hydrogel can absorb water from the surrounding air to regenerate its water content later on. This reversibility can be finely designed. As an applicative demonstration, the hydrogel film with a thickness of 2 mm was attached to a cell phone battery while operating. It successfully decreased the temperature of the battery by 20 °C and retrieved electricity of 5 μW at the discharging rate of 2.2 C.
高效的热量移除和回收是两个相互矛盾的过程，很难同时实现。在这里，我们通过使用智能热电水凝胶薄膜开辟了一条新的途径来实现这一目标，其中离子和水经历两个独立的热力学循环：热电反应和水到蒸汽相变。当水凝胶附着在热源上时，它可以实现高效的蒸发冷却，同时将一部分废热转化为电能。此外，水凝胶可以从周围空气中吸收水分，稍后再将其水合。这种可逆性可以进行精细设计。作为应用示范，将厚度为 2 毫米的水凝胶薄膜附着在正在运行的手机电池上。它成功地将电池温度降低了 20°C，并以 2.2 C 的放电率回收了 5 μW 的电量。
