武汉大学李振&聊城大学李茜&李爱森等:通过压力作用在具有电荷转移特性的共价有机框架中实现从红光到近红外发光的大范围位移调控

2026-08-26 06:05:22

近红外压致变色材料在机械传感器和存储设备等领域具有重要应用。共价有机框架（COFs）兼具可灵活调控的结构与光物理性质，在压致变色领域前景广阔，但目前相关研究仍十分有限。

近日，武汉大学李振教授、聊城大学李茜教授和李爱森博士等人在Science China Materials发表研究论文，合成了一系列给体-受体结构的二维COFs，在压力作用下均表现出覆盖红至近红外区域的显著红移。

本文要点

1) 其中，Py-BO-COF压致变色位移高达187 nm，灵敏度为44.52 nm GPa⁻¹，显著优于同类及已报道材料。

2) 该化合物在经过多次循环使用后，仍保持完全可逆的发光切换，线性良好且强度无衰减。

3) 结合原位光谱与理论模拟发现，压致变色速率差异源于电荷转移过程强弱，Py-BO-COF的显著红移与层间距缩小及分子共面性增强密切相关。

本研究系统建立了结构-性能关系，为设计高性能可逆压致变色材料提供了新思路。

Figure 1.Schematic diagram of the synthetic routes of three COFs (TPE-BO-COF, Py-BT-COF, and Py-BO-COF) with piezochromic behaviors.

Figure 2.(a) FT-IR spectra of BT-CHO, Py-NH₂, and Py-BT-COF. (b) PXRD patterns of Py-BT-COF. (c) N₂ adsorption-desorption isotherm of Py-BT-COF. Inset: pore size distribution. (d) FT-IR spectra of BO-CHO, TPE-NH₂, and TPE-BO-COF. (e) PXRD patterns of TPE-BO-COF. (f) N₂ adsorption-desorption isotherm of TPE-BO-COF. Inset: pore size distribution. Normalized PL spectra of Py-BT-COF (g) and TPE-BO-COF (h) under UV irradiation (λex = 365 nm) during the compression process. (i) PL wavelength plots of Py-BT-COF and TPE-BO-COF at various pressures.

Figure 3.(a) FT-IR spectra of BO-CHO, Py-NH₂, and Py-BO-COF. (b) PXRD patterns of Py-BO-COF. (c) N₂ adsorption-desorption isotherm Py-BO-COF. (d) Normalized PL spectra of Py-BO-COF upon compression excited by 365 nm. (e) PL wavelength of Py-BO-COF at various pressure values (the straight line represents the linear fit of wavelength, and the slope indicates the pressure coefficient). (f) Comparison of the pressure-responsive sensitivity of the typical piezochromic MOFs/COFs in the previous literature. (g) Linear regression fittings on the PL wavelength against pressure over multiple cycles. (h) PL wavelength and corresponding images of Py-BO-COF changes upon compression-decompression process over five cycles.

Figure 4.(a) UV-vis absorption spectra of Py-BT-COF, TPE-BO-COF, and Py-BO-COF. (b) In situ UV-vis absorption spectra of Py-BO-COF under high pressure. (c) Absorption edge of Py-BO-COF, TPE-BO-COF, and Py-BT-COF varies with pressure. In situ FT-IR spectra of Py-BO-COF under pressure conditions, 790–1159 cm⁻¹ (d) and 1300–1700 cm⁻¹ (e). (f) Corresponding pressure-dependent evolution of characteristic vibrational modes including δ(C–H), ν(C=C), and ν(C=N).

【通讯作者简介】

Aisen Li(李爱森) received her PhD degree from Jilin University in 2020. She has been working at Liaocheng University since 2023. Her research interests are in mechanoresponsive organic luminescent materials.

Qian Li (李茜) received her PhD degree from Jilin University in 2015. She has been a full Professor at Liaocheng University since 2022. Her research interests are in optical functional materials under high pressure.

Zhen Li (李振) received his BSc and PhD degrees from Wuhan University (WHU) in 1997 and 2002, respectively. He has been a full professor at WHU since 2006. His research interests focus on the design and synthesis of organic molecules and polymers with novel structures and functions for applications in organic electronics and photonics.