A cubic porphyrin-based covalent organic framework (COF) named CTP with excellent hydrophilicity was prepared with a facile method for the first time. Different from the conventional methods for the synthesis of porphyrin-based COFs, this facile strategy has greatly shortened the reaction time under mild conditions. Linking the porphyrin monomer into the COF overcame its poor solubility and biocompatibility and also narrowed the band gap owing to the formation of the π-conjugation structure. The improved biocompatibility and narrowed band gap enabled CTP to be an excellent sonosensitizer with an enhanced sonodynamic effect. Moreover, CTP could also effectively realize photothermal conversion under external irradiation due to the extended conjugated structure. This work developed a novel synthesis method for COFs and employed a COF as a sonosensitizer for the first time, which not only provided a new strategy to improve the efficiency of organic sonosensitizers but also inspired us to design more functional COFs for versatile applications.

Liquid crystalline elastomers (LCEs) are lightly crosslinked polymers that combine liquid crystalline order and rubber elasticity. Owing to their unique anisotropic behavior and reversible shape responses to external stimulation (temperature, light, etc.), LCEs have emerged as preferred candidates for actuators, artificial muscles, sensors, smart robots, or other intelligent devices. Herein, we discuss the basic action, control mechanisms, phase transitions, and the structure–property correlation of LCEs; this review provides a comprehensive overview of LCEs for applications in actuators and other smart devices. Furthermore, the synthesis and processing of liquid crystal elastomer are briefly discussed, and the current challenges and future opportunities are prospected. With all recent progress pertaining to material design, sophisticated manipulation, and advanced applications presented, a vision for the application of LCEs in the next generation smart robots or automatic action systems is outlined.

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Enhance light absorption in two-dimensional (2D) materials are of great importance for the development of many optoelectronic devices such as photodetectors, modulators and thermal emitters. In this paper, a resonant nanostructure based on subwavelength gratings of monolayer molybdenum disulphide (MoS2) is proposed. It is shown numerically that the excitation of guided modes in the proposed structure leads to perfect absorption in the visible range. The linewidth of the absorption spectrum can be narrow down to 0.1 nm. The resonance wavelength exhibits an almost linear dependence on the incidence angle. The proposed structure provides a method to design ultra-narrowband absorbers and similar designs can be applied to other 2D materials. It may find applications for optical filters, directional thermal emitters, 2D materials based lasers and others.