Wang Zhihua, Cheng Puxin, Han Wenqing, Shi Rongchao, Xu Jian, Zheng Yongshen, Xu Jialiang, Bu Xian-He
School of Materials Science and Engineering, Tianjin Key Laboratory of Metal and Molecular Materials Chemistry, Frontiers Science Center for New Organic Matter, Nankai University, Tianjin 300350, People's Republic of China.
China Petroleum & Chemical Corporation (Beijing) Research Institute of Chemical Industry Co., Ltd. Yanshan Branch, Beijing 102500, People's Republic of China.
Proc Natl Acad Sci U S A. 2025 Feb 18;122(7):e2417901122. doi: 10.1073/pnas.2417901122. Epub 2025 Feb 10.
Adaptive crystals have attracted significant attention from solid-state chemists and crystal engineers for their promising applications in memories, capacitors, sensors, and actuators. Among them, thermosalient crystals are particularly favored thanks to their efficient energy conversions and rapid responses. However, the mechanisms for the mechanical responses of thermosalient crystals remain largely unclear. Herein we demonstrate that thermosalient effects of molecular crystals could be driven by thermoelastic twisting behaviors. The crystal, based on a model compound with rigid dibenzothiophene sulfone planes and flexible ethoxy chains, can spontaneously self-heal from mechanical fractures. Upon heating, the crystal undergoes remarkable thermosalient behaviors driven by a distinctive left- or right-handed twisting. This thermoelastic twisting converts thermal energy into elastic potential energy, which is further released as kinetic energy upon untwisting to drive the crystal jump. Our demonstration on thermoelastic twisting-induced crystal jumping offers a different perspective on the origins of thermosalient crystals and could provide inspiration for future engineering and application of dynamic molecular crystals.
自适应晶体因其在存储器、电容器、传感器和致动器等方面的潜在应用，已引起固态化学家和晶体工程师的广泛关注。其中，热响应性晶体因其高效的能量转换和快速响应而备受青睐。然而，热响应性晶体的机械响应机制仍不清楚。在此，我们证明分子晶体的热响应效应可能由热弹性扭曲行为驱动。该晶体基于一种具有刚性二苯并噻吩砜平面和柔性乙氧基链的模型化合物，能够从机械断裂中自发自我修复。加热时，该晶体通过独特的左旋或右旋扭曲表现出显著的热响应行为。这种热弹性扭曲将热能转化为弹性势能，在扭曲解开时进一步释放为动能，驱动晶体跳跃。我们对热弹性扭曲诱导晶体跳跃的论证为热响应性晶体的起源提供了不同视角，并可为动态分子晶体的未来工程设计和应用提供灵感。
