The effective capture of radioactive volatile iodine ( 131 I and 129 I) from nuclear waste stream is of vital significance. In this work three kinds of porous organic frameworks (POFs) knitting with N -containing building units were constructed via cost-effective and maneuverable Scholl reaction. The obtained PAFs exhibited moderate porosity and satisfying thermal stability. With coexistence of open porous structure, the electron-rich amino group featured with π-π interactions was found to improve the affinity to iodine, and the iodine uptake capacities were 408 wt%, 335 wt% and 268 wt% when the prepared POFs of P-DPDA, P-TPB and P-PC were employed for the adsorption experiments. The results were superior to most of the porous adsorbents including zeolite , metal-organic frameworks (MOFs) and porous organic polymers (POPs). Iodine adsorption capacities of 289.50 mg g −1 (for P-DPDA), 194.63 mg g −1 (for P-TPB) and 259.69 mg g −1 (for P-PC) in organic solution were achieved, and the adsorbed iodine molecules could be released to ethanol. Such promising and cost-effective materials can be envisaged for application in the field of nuclear waste management.
Fluorescent antifouling is a method that utilizes substances fluorescent repellent effect to prevent organisms attachment and fouling. It is considered one of the directions for developing environmentally friendly marine antifouling materials. The current fluorescent antifouling materials were characterized by issues such as single functionality, unclear antifouling mechanisms, and suboptimal antifouling performance. In this study, three carbazole derivatives containing carbon–carbon double bonds were synthesized by Friedel-Crafts alkylation reaction, and a series of zinc acrylate resins containing carbazole derivative structures were further synthesized through free radical polymerization. Three carbazole derivatives were tested for their fluorescence and their growth inhibition properties against bacteria and algae. The results showed that the three carbazole derivatives not only had high fluorescence intensity, but also had good inhibitory effects on bacteria and algae, with the highest inhibition rate of 81% on algae. The fluorescence properties, algal inhibition properties and anti-algal adhesion properties of the resin were investigated. The results showed that the fluorescence intensity of the resin was enhanced with the increase of carbazole derivative content. The inhibition rate of the resin against algae was as high as 88.5%, and the anti-algal adhesion rate of the resin was improved under light conditions. Mechanistic studies showed that the resin influenced the cell wall, and the fluorescence caused the algae to prioritize photosynthesis rather than attachment and settlement. Self-polishing performance test results showed that the introduction of carbazole derivatives improved the stability of the resin. The results of the real sea antifouling test show that the resin integrates fluorescence, chemical activity and self-polishing, and has excellent antifouling performance. This provides a theoretical basis for the development of environmentally friendly marine antifouling materials.
Wang Yifan,Dong Wenjian,Yan Xuefeng,Li Xia,Yu Liangmin
Tin-free self-polishing antifouling coatings are prevalent today. However, its high Cu 2 O content endangers the marine environment. Leveraging the fluorescent properties of coating to prevent fouling is an environmentally friendly antifouling coating development. In this paper, four unreported fluorescent structural carbazole amide derivatives (FSCAD) were synthesized by Friedel–Crafts alkylation reaction. Their fluorescence, antibacterial, and algal inhibition properties were examined. The fluorescent properties test results showed that the four FSCAD exhibited high fluorescence properties. The results of antibacterial test and anti-algae growth test showed that the maximum bacterial inhibition rate can reach 90%, and the growth inhibition rate of three kinds of microalgae can reach more than 75%. It was added to the antifouling coating system as an antifouling agent instead of the traditional antifouling agent Cu 2 O. The abrasion rate, contact angle, surface morphology, and roughness of the coatings were determined by dynamic simulation experiments, and the antifouling properties of the coatings were evaluated by the anti-algae sedimentation test and marine environment antifouling experiments. The results of dynamic simulation experiments showed that adding FSCAD does not affect the wettability and surface state of the coating. Anti-algae sedimentation test exhibited that marine antifouling coatings with FSCAD showed excellent inhibition on the sedimentation of microalgae. The anti-fouling performance of the coating was tested in the marine environment antifouling experiments. The results showed that the coating exhibited excellent anti-fouling performance, with minimal biofouling was attached to the surface of the coating. Especially, the antifouling performance with compound A was better than that of chlorothalonil. Graphical abstract