Polydopamine-based polysaccharide materials for water treatment

Abstract

Low-cost polysaccharides, such as cellulose, chitosan, chitin and alginate, have come into people's sight for water treatment. Nevertheless, their treatment e ciency and capability are sometimes unsatisfactory because of the lack of active sites and functionalities. In recent years, more and more attentions have been paid to the integration of polydopamine (PDA) into polysaccharide-based materials to develop highperformance products for wastewater treatment. PDA modi cation can endow polysaccharides with plentiful functional moieties (including catechol, amine, and phenyl groups) for binding heavy metals and organic pollutants. PDA coatings may increase interfacial stability and hydrophilicity for oil/water separation. PDA also may anchor various catalysts for catalytic degradation of organic pollutants.Furthermore, the good light-harvesting capability and photothermal transformation feature of PDA are available for solar-driven water puri cation. This review aims to give the comprehensive overview on the development of PDA-based polysaccharide materials for water treatment. PDA-based polysaccharide materials can be made into cost-effective and high-performance products (including hydrogels, aerogels, membrane, beads and nanocomposites) for adsorption of heavy metals and organic pollutants, oil/water separation, catalytic degradation of organic pollutants, and solar-driven water puri cation. This review will give a valuable information for the design and exploitation of PDA-based polysaccharide materials in water treatment.

Polycondensation-Involved Melanin-like Polymers for Enhanced Solar Energy Utilization

“…Because of the severe environment pollution and explosive population growth, fresh-water scarcity is among the most serious crises across the world. As a simple and green method, solar-driven interfacial water evaporation has received increasing attention in seawater desalination as well as in wastewater purification. − Owing to the admirable performance in solar energy gathering, photothermal conversion, and adhesive property, the prepared PDHI-5 NPs were further applied to fabricate the solar interfacial evaporator. As illustrated in Figure a, the PDHI-5 NP-coated hydrophilic PES (PES@PDHI-5) membrane served as a photothermal layer to absorb sunlight and convert into thermal energy.…”

Self-Healing Hydrogels: From Synthesis to Multiple Applications

“…The aggregation form of hydrogels is neither solid nor liquid but a special form between solid and liquid. Almost all hydrophilic polymers can be used to form hydrogels. − According to the different synthetic materials, they can be divided into natural polymer (including cellulose, chitosan, alginate, and gelatin) hydrogels − and chemically synthesized (including poly­(vinyl alcohol), poly­(acrylic acid), and poly­(ethylene glycol)) hydrogels. − According to different cross-linking types, they are also sorted into physical cross-linking hydrogels, − chemical cross-linking hydrogels , and physical/chemical dual cross-linking hydrogels. − Due to their good biocompatibility, biodegradability, and flexibility, hydrogels are appropriate for applications in wound healing, − as drug carriers, , in tissue engineering, , as sensors, − actuators, − and wearable electronics, , in catalysis, in solar water purification, − as supercapacitors, , etc.…”

Development of an Antioxidant and UV-Shielding Composite Hydrogel Using Mussel-Inspired Cellulose Nanocrystals, Polydopamine, and Poly(vinyl alcohol) for Application in Sunscreens

“…Inspired by mussels, Messersmith et al discovered that dopamine can form polydopamine (PDA) via self-polymerization and that PDA can serve as a potential coating material. Subsequently, PDA has been widely employed for the surface modification of various materials . Notably, PDA has physicochemical properties similar to those of eumelanins and contributes to the UV-shielding and radical-scavenging functions, which can protect the skin from UV rays by scavenging free radicals and preventing their penetration into the skin. , Thus, these promising features make PDA-containing gels ideal candidates as safe and efficient UV-shielding materials. − …”