Laser-reduced graphene oxide for a flexible liquid sliding sensing surface.

Flexible electronic skin is a flexible sensor system that imitates human skin. Recently, flexible sensors have been successfully developed. However, the droplet sliding sensing technology on a flexible electronic skin surface is still challenging. In this Letter, a flexible droplet sliding sensing surface is proposed and fabricated by laser-reduced graphene oxide (LRGO). The LRGO shows porous structures and low surface energy, which are beneficial for infusing lubricants and fabricating stable slippery surfaces. The slippery surface guarantees free sliding of droplets. The droplet sliding sensing mechanism is a combination of triboelectricity and electrostatic induction. After a NaCl droplet slides from lubricant-infused LRGO, a potential difference (∼0.2 mV) can be measured between two Ag electrodes. This study reveals considerable potential applications in intelligent robots and the medical field.

Photothermal responsive slippery surfaces based on laser-structured graphene@PVDF composites.

Photothermal responsive slippery surfaces with switchable superwettability are promising in the fields of biomedicine, self-cleaning, anti-corrosion, and lab-on-a-chip systems. However, the development of a light switchable slippery surface that combines high-performance photothermal materials with hierarchical microstructures of special orientation remains challenging, which limits the applications in anisotropic droplet manipulation. Herein, we demonstrate a photothermal responsive slippery surface based on laser-structured graphene and polyvinylidene difluoride composites (L-G@PVDF) for controllable droplet manipulation. The L-G@PVDF film exhibits high light absorption (∼95.4%) in the visible and NIR region. After lubricating with paraffin, the resultant surface shows excellent self-healing ability and light-responsive wettability change due to the photothermal effect of L-G@PVDF and the hot melting effect of paraffin. Additionally, by introducing anisotropic grooved structures, the paraffin-infused L-G@PVDF surface displays anisotropic wettability that further affects droplet manipulation under light irradiation. Also, the photothermal responsive slippery property endows the paraffin-infused L-G@PVDF surface with excellent anti-frosting and de-icing capability. Moreover, the smart paraffin-infused L-G@PVDF surface can be combined with a microfluidics chip for light-driven automatic sampling. This study offers insight into the rational design of photothermal responsive slippery surfaces for controllable droplet manipulation.

Fabrication of anti-icing/de-icing surfaces by femtosecond laser.

In this minireview, we comprehensively reviewed recent progress on fabricating anti-icing/de-icing surfaces by femtosecond laser technologies. Typical bioinspired micro-/nano-structures fabrication strategies, superhydrophobic surfaces with anti-icing properties, and photothermal surfaces with de-icing properties are summarized. At last, we discussed challenges and prospects in anti-icing/de-icing surfaces fabricated by femtosecond laser technologies.

Micro-/Nano-Structures Fabricated by Laser Technologies for Optoelectronic Devices.

Due to unique optical and electrical properties, micro-/nano-structures have become an essential part of optoelectronic devices. Here, we summarize the recent developments in micro-/nano-structures fabricated by laser technologies for optoelectronic devices. The fabrication of micro-/nano-structures by various laser technologies is reviewed. Micro-/nano-structures in optoelectronic devices for performance improvement are reviewed. In addition, typical optoelectronic devices with micro-nano structures are also summarized. Finally, the challenges and prospects are discussed.