A dual-functional lignin containing pulp foam for solar evaporation and contaminant adsorption

Recently, solar-driven evaporator has been widely investigated as an environmentally benign and sustainable method in water desalination and purification, but its evaporation efficiency is highly reliant on solar intensity, and the increased contamination in water can hinder the production of clean water. Herein, we designed a novel and scalable polydopamine-functionalized lignin containing pulp (LPNR@PDA) foam evaporator with the dual-purpose of high-efficiency desalination and multi-contaminant adsorption. With excellent light absorption (90 %), high water absorption ability (9.5 g g-1), low thermal conductivity (0.1 W mK-1) and chelation capabilities, the LPNR@PDA foam evaporator synergized solar evaporation and contaminant adsorption with one another, making the LPNR@PDA foam evaporator a desirable material with the capability of continuous clean water production in all-weather conditions. Additionally, the LPNR@PDA foam evaporator with unique porous structure presented potential applications in treatments of metal ion concentration and contaminated seawater, and also the LPNR foam exhibited excellent biodegradability in the natural environment compared to poly-styrene foam. Therefore, this novel foam material will shine a new light for developing multifunctional photo -thermal system for solar-driven water purification.

Automated summary

In this study, a novel polydopamine-functionalized lignin-containing pulp foam evaporator with high-efficiency desalination and multi-contaminant adsorption capabilities was designed. The foam evaporator showed excellent light absorption, water absorption, thermal conductivity, and chelation abilities, allowing for solar evaporation and contaminant adsorption synergistically. It also exhibited potential applications in metal ion concentration and contaminated seawater treatments, and demonstrated superior biodegradability compared to poly-styrene foam. This foam material holds promise for developing multifunctional photo-thermal systems for solar-driven water purification.