Stimuli-Responsive Organic Phase Change Materials: Molecular Designs and Applications in Energy Storage
Stimuli-Responsive Organic Phase Change Materials: Molecular Designs and Applications in Energy Storage
复制标题
DOI：
10.1021/accountsmr.2c00049
复制
发表时间：
2022-06-24
影响因子：
14.6
通讯作者：
Han, Grace G. D.
中科院分区：
文献类型：
--
作者：
Le, My;Han, Grace G. D.
在较大的温度范围内实现稳定的潜热存储，并长时间实现从常规相变材料中完成受控的热量释放的热量材料，这在热能控制方面仍然是巨大的挑战。由于常规相变材料在标准环境压力下具有固定相变温度，因此潜在热量仅在高于其熔化和结晶点的温度下可行。一旦潜在的热量存储在材料的液相中，就必须将系统的温度保持在其结晶点以上的温度以延长热量存储。如果没有连续的能量输入或广泛的绝缘材料，液体的结晶会自发发生，从而导致潜在热量损失和较短的热量存储时间。因此，存在着开发方法的迫切需求，以使材料的相变控制，这是不受周围环境温度的不受限制的。近年来，通过纳入对外部刺激的分子开关（尤其是光线，电化学偏见和离子），通过可逆的结构变化，这种方法和材料的成功开发是可行的。我们已经发现了新型的功能性有机材料系统，这些系统表现出由光学和电刺激控制的固体到液相变，以及其他研究组。此类材料的开发和优化是通过明智的分子设计和合成来实现的。在此帐户中，我们将介绍可控相变的尖端设计原理，这些材料已经证明了热能的存储长达几个月在较宽的温度范围内没有结晶，从亚零到100度以上，这解决了常规相变材料的主要弱点。特别是，通过太阳照射控制的材料和表现出大量重量级能密度的化合物，这将指导实用储能应用的功能材料的进一步开发。可控的储热材料不仅会回收浪费的太阳能热能，而且还可以改善工业过程中的巨大能量损失。特别是，在低于100摄氏度的温度下释放的废热可以有效地吸收并存储在有机相变材料中，这些材料无法通过其他能量转换和存储系统（包括热电和电池）轻松地收回。这种互补的存储方法将通过回收浪费的能量来利用各种废热来源，并减少化石燃料的消耗，这将有助于缓解气候变化。
Achieving a stable latent heat storage over a wide temperature range and a long period of time as well as accomplishing a controlled heat release from conventional phase change materials have remained prominent challenges in thermal energy control. Because the conventional phase change materials have the fixed phase transition temperatures under the standard ambient pressure, the latent heat storage is only viable at temperatures higher than their melting and crystallization points. Once the latent heat is stored in the liquid phase of materials, it is imperative to maintain the temperature of the system above its crystallization point to prolong the heat storage. Without the continuous energy input or extensive insulation, the crystallization of liquid occurs spontaneously, leading to the loss of latent heat and a short heat storage time. Thus, there exists a critical need to develop methods that enable the control over the phase transition of materials, unrestricted by the temperature of the surroundings. The successful development of such methods and materials in recent years has been viable through the incorporation of molecular switches that respond to external stimuli, notably light, electrochemical bias, and ions, by reversible structural changes. We have discovered novel functional organic material systems that exhibit solid-to-liquid phase transitions controlled by optical and electrical stimulation, along with other research groups. The development and optimization of such materials are enabled by the judicious molecular designs and syntheses.In this Account, we will introduce the cutting-edge design principles of controllable phase change materials that have demonstrated the storage of thermal energy for up to a couple of months without crystallization over a wide temperature range, from subzero to over 100 degrees C, which addresses the major weakness of conventional phase change materials. In particular, materials that are controlled by solar irradiation and compounds that exhibit substantial gravimetric energy densities are presented, which will guide the further development of functional materials for practical energy storage applications. The controllable heat storage materials will not only recycle the wasted solar thermal energy but also ameliorate massive energy loss in industrial processes. In particular, the waste heat released at temperatures below 100 degrees C can be effectively absorbed and stored in organic phase change materials, which cannot be easily reclaimed by other energy conversion and storage systems, including thermoelectrics and electrical batteries. This complementary storage method will harness various sources of waste heat and reduce the consumption of fossil fuels by recycling the wasted energy, which will contribute to mitigating climate change.