Hygroscopic salt-hydrogel-based atmospheric water harvesting (HAWH) technology represents an auspicious approach to alleviating the water crisis, as it is not limited by factors such as climactic. Reducing hygroscopic salt leakage is of the utmost importance to maintaining the technology's consistent performance. Consequently, we have developed a composite hygroscopic material (PPy-AAC-LiCl) with in situ loaded polypyrrole (PPy) as a photothermite. The in-situ loading of PPy not only achieves the photothermal performance of PPy-AAC-LiCl but also enhances the hygroscopic performance, which is due to the presence of nitrogen atoms in the structure facilitating the formation of hydrogen bonds between water molecules, and reduces the leakage of hygroscopic salts attributed to its ability to inhibit the increase in pore size after hygroscopicity of PPy-AAC-LiCl. The experimental results show that PPy-AAC-LiCl has effective hygroscopic performance at relative humidity (RH) of 30 %–90 %. The hygroscopicity at 25 °C and RH 70 % was about 1.53 g water g adsorbents −1 after 12 h. After ten hygroscopicity-desorption cycles, the hygroscopicity of the samples did not decrease significantly, and no white crystals appeared on the surface of the samples during the desorption process. Furthermore, PPy-AAC-LiCl demonstrated effective atmospheric water harvesting capabilities in outdoor trials, exhibiting a desorption rate of 87.6 % and a moisture absorption rate of 1.26 g water g adsorbents −1 . The preparation of this simple and environmentally friendly hygroscopic composite material lays the foundation for the future development of atmospheric water materials.
Biomimetic surfaces that can manipulate droplets have attracted intense attention because of their application prospects in the fields of drug detection, cell sorting, bio-sensor, etc. Although many promising advances have been made, it is still a challenge to achieve lossless, no cross-contamination and on-demand controllable manipulation of underwater oil droplets without external energy input. Herein, SHI & SLIP interlaced wetting smart surfaces were fabricated by a simple strategy for manipulating underwater oil droplets. Depending on the switchable wettability and reasonable alternating wetting, the lubricant-infused area and superhydrophilic area can be on-demand controlled on the same surface. Numerical calculation and theoretical analysis reveal that the energy barrier between different interfaces is an important factor to realize underwater oil droplet manipulation. By the rational design of the interlaced wetting pattern, the capture, lossless transfer, fusion and directional transportation of underwater oil droplets were realized. Besides, the as-prepared surface has cross-contamination resistance, stable wettability and rewritability, which expands the application field and improves the potential value. We expect this work to open new avenues for flexible and controllable manipulation of underwater oil droplets and promote the development of smart microfluidic platform. It is also expected to be used in unpowered delivery systems, micro-reactions and energy transfer.
危险品化学品经营许可证（带存储）