Tong Liu,Dawei Zhang,Lingwei Ma,Yao Huang,Xiangping Hao,Herman Terryn,Arjan Mol,Xiaogang Li
Herein, we report the development of a self-sensing and active corrosion protection coating which incorporates pH-sensitive multilayer chitosan/alginate-covered CaCO 3 microcontainers containing 1,10-phenanthrolin-5-amine (APhen). The microcontainers can respond to pH variation to release APhen which serves not only as a corrosion indicator but also as an inhibitor. An epoxy coating doped with 5 wt% microcontainers exhibited improved corrosion performance and was capable of inhibiting corrosion spreading from the damaged area in a 3.5 wt% NaCl solution. The salt spray test showed that corrosion damage can be quickly detected by the appearance of a red color within 2 min.
Guomin Ding,Weicheng Jiao,Liuyang Chen,Meiling Yan,Lifeng Hao,Rongguo Wang
Smart superhydrophobic surfaces with controllable adhesion behavior or sensing capability have become a research hotspot in many areas, such as self-cleaning and microdroplet transportation. Herein, we design and fabricate a superhydrophobic, open-cell graphene network with a polypropylene coating (PP/OCGN) via a new method of boiling coating. The adhesive force of PP/OCGN for water droplets can be controlled easily from 66.8 μN to 32.3 μN by adjusting the soaking time. Using the PP/OCGN with controllable adhesion behavior, the lossless transportation of water microdroplets has been achieved. What's more, because of the boiling coating process, the PP/OCGN exhibits a heterogeneous network, which has the coated graphene on the surface and the uncoated graphene in the inner part. By means of the special network and strong water repellency of PP/OCGN, we report for the first time a conductive, superhydrophobic graphene material with a self-sensing capability for continuously falling water droplets. When the water droplets fall on the surface, the PP/OCGN with low adhesive force not only makes the droplets bounce off successfully, but also has a rapid response to the bouncing process through changing the resistance. The size of falling water droplets can also be determined. Therefore, our multifunctional superhydrophobic PP/OCGN can meet multiple needs simultaneously, such as self-cleaning and detecting raindrops, and it has great application prospects in the future.
Min Ge,Shiyan Han,Yanli Ma,Jian Li,Shouxin Liu,Zhijun Chen,Shujun Li
Mechanofluorochromic carbon dot-based aggregation-induced emission luminogens (M-CD-AIEgens) are attracting much attention because of their many potential practical applications. However, the mechanofluorochromic response of current M-CD-AIEgens only occurs under high pressure, which greatly hinders their practical applications. To overcome this shortcoming, more pressure-sensitive M-CD-AIEgens are now developed, which show approximately fivefold enhancement of photoluminescence quantum yield after grinding. This enhancement of photoluminescence is attributed to the weakening of π–π stacking interactions between the carbon dots, which is caused by the grinding process. To illustrate a potential application of their interesting properties, M-CD-AIEgens are incorporated into a poly( e -caprolactone) matrix to prepare self-sensing sustainable plastics, which are able to dynamically sense the external pressure distribution when subjected to strain.