Dictyophora-based evaporator developed by sericin bidirectional crosslinking for photocatalytic degradation and efficient solar desalination in harsh environments
Qian Yang, Junkai Gao, Mengsheng Xia, Jingkang Fang, Weipeng Wu, Yan Chen
Abstract
This study introduces a novel dictyophora-based evaporator , SCNT/TiO 2 @PAM-DIC, developed through a pioneering sericin bidirectional crosslinking strategy. This innovative material boasts a range of advantages, including environmental friendliness, salt resistance, antibacterial properties , acid and alkali resistance, oil repellency , and pressure resistance. By incorporating polyacrylamide (PAM) hydrogel enhanced with sericin, SCNT/TiO 2 @PAM-DIC significantly improves the mechanical strength of dictyophora while offering anti-fouling, antibacterial, and high-efficiency evaporation capabilities. Unlike its predecessor DIC, SCNT/TiO 2 @PAM-DIC retains a porous structure with a smoother surface, enabling multiple sunlight reflections and prolonged exposure, which enhances its solar absorption to an impressive 93 %. Photothermal conversion studies reveal that SCNT/TiO 2 @PAM-DIC achieves a surface temperature of 63.5 °C within 5 min, surpassing DIC (29.1 °C) and S@PAM-DIC (30.9 °C). The evaporation rate of SCNT/TiO 2 @PAM-DIC is significantly higher at 2.495 kg m −2 h −1 , compared to 1.149 kg m −2 h −1 for DIC and 1.433 kg m −2 h −1 for S@PAM-DIC. Additionally, its dark evaporation rate is 1.8 times that of pure water. The material's exceptional salt rejection and self-cleaning properties are attributed to the presence of zwitterionic groups in its structure. Mechanically, SCNT/TiO 2 @PAM-DIC demonstrates superior compressive performance and stability, with compressive stresses of 0.516 MPa at a 25 % compression ratio, significantly higher than DIC's 0.104 MPa. Furthermore, it achieves an 83.5 % photocatalytic degradation efficiency of methylene blue within 3 h. Its robust performance in challenging environments, such as oily wastewater, emulsified oil, organic dyes, and acidic/alkaline solutions, positions SCNT/TiO 2 @PAM-DIC as a promising solution for advanced water purification technologies , offering a new avenue for sustainable water treatment.