Scalable fabrication of monolithic porous foam based on cross-linked aromatic polymers for efficient solar steam generation

Cost-effective and scalable solution to fabricate high-performance photothermal materials is the key to enable widespread application for solar steam generation. Herein, we report the facile and scalable fabrication of monolithic porous foam based on cross-linked aromatic polymer (PDVB-PS) using styrene as monomer and divinylbenzene as cross-linking agent through a facile one-step hydrothermal method. The resulting PDVB-PS foam possesses well-controlled porous structure, open channel structure, low apparent density and low thermal conductivity (0.038Wm(-1)k(-1)). After modification with sodium alginate and polypyrrole, the as-modified PDVB-PS (named as PPy-coated M-PDVB-PS) shows a superhydrophilic wettability (water contact angle similar to 0 degrees) and stronger light absorption (ca. 90%), which could dramatically enhance its water transportation ability and photothermal property. Taking advantages of these unique physicochemical properties mentioned above, a high solar-vapor conversion efficiency of 87.6% for the PPy-coated M-PDVB-PS was obtained under 1-sun irradiation, showing great potentials for real applications. More importantly, as a kind of representative synthetic polymers, the success in employment of the PPy-coated M-PDVB-PS as efficient photothermal materials shown in this study may also open a new opportunity for rational design and fabrication of polymer-based solar generators derived from commercial available low-cost raw chemicals with simple and scalable manufacture process for practical solar steam generation on large scale.