Chenxi Li,Donglei Li,Mingting Zhang,Bo You,Zonglin Wu,Yulin Tao,Yaojie Sun,Limin Wu,Xiaoliang Mo
Modern miniaturized intelligent electronics call for smart switchable and flexible electromagnetic interference (EMI) shielding material for highly precise applications. However, most switchable EMI shielding materials are based on an explicit structural change. Herein, we report a succulent-inspired smart switchable MXene (WR-MXene) coating film realized by inner implicit structural change, which benefits from the insertion of our reversible large-cavity yolk–shell biomicrospheres. The novel switchable yolk–shell biomicrospheres contain a soft N-isopropylacrylamide (PNIPAM) hydrogel core, an “ON/OFF” switchable cavity (over 30% volume fraction), and a porous polydopamine (p-PDA) shell. The yolk–shell biomicrospheres can be obtained by a facile two-step polymerization and a simple drying-dehydration treatment. Because of the “ON/OFF” switchable void space brought by the smart biomicrospheres and conductive framework of MXene, an optimized ultralight and flexible WR-MXene coating film (vWR-coating film) showed both large switchable change (over 60 dB) and extraordinary EMI shielding effectiveness, reaching 95 and over 50 dB in the whole X band (8.2–12.4 GHz). These novel reversible yolk–shell biomicrospheres and the succulent-inspired switchable coating films are promising for smart flexible wearable devices and many advanced multifunctional systems needing dynamic real-time response.
Yi Pan,Zhenyu Yang,Chang Li,Sammer Ul Hassan,Ho Cheung Shum
The healthy functioning of the plants’ vasculature depends on their ability to respond to environmental changes. In contrast, synthetic microfluidic systems have rarely demonstrated this environmental responsiveness. Plants respond to environmental stimuli through nastic movement, which inspires us to introduce transformable microfluidics: By embedding stimuli-responsive materials, the microfluidic device can respond to temperature, humidity, and light irradiance. Furthermore, by designing a foldable geometry, these responsive movements can follow the preset origami transformation. We term this device TransfOrigami microfluidics (TOM) to highlight the close connection between its transformation and the origami structure. TOM can be used as an environmentally adaptive photomicroreactor. It senses the environmental stimuli and feeds them back positively into photosynthetic conversion through morphological transformation. The principle behind this morphable microsystem can potentially be extended to applications that require responsiveness between the environment and the devices, such as dynamic artificial vascular networks and shape-adaptive flexible electronics.
危险品化学品经营许可证（带存储）