3D MnO2/GO-cellulose sponge enabling salt-resistant interfacial evaporation and efficient antibiotic degradation

Monolithic MnO 2 /GO-cellulose sponge couples solar evaporation with photocatalytic antibiotic degradation. • Evaporation rate of 1.40 kg m −2  h −1 and 85% tetracycline degradation achieved under one sun. • 78% degradation efficiency maintained in 10 wt% NaCl with zero surface salt crystallization. • “Mesopore-concentration and macropore-reflux” mechanism enables robust salt resistance. Simultaneous antibiotic removal and salt resistance remain a promising yet challenging frontier in solar-driven interfacial evaporation. Herein, we fabricated a three-dimensional super-hydrophilic cellulose sponge integrated with a MnO 2 /GO composite (MGCS) via polydopamine-assisted deposition, successfully coupling photothermal steam generation with photocatalysis. This composite architecture enables efficient broadband solar harvesting and suppresses photogenerated electron–hole recombination, thereby enhancing both photothermal evaporation and photocatalytic degradation. Under one sun irradiation, MGCS delivers an evaporation rate of 1.40 kg m −2  h −1 and degrades 85% of tetracycline (15 mg L −1 , 150 min). Crucially, in a 10 wt% NaCl matrix, the system maintains a 78% degradation efficiency with zero surface salt crystallization over 24 h of continuous operation. This exceptional salt tolerance originates from a synergistic anti-fouling mechanism driven by the negatively charged, super-hydrophilic surface and a dynamic “mesopore-concentration and macropore-reflux” structural architecture. Ultimately, this monolithic platform provides a robust material framework for purifying complex, hypersaline wastewaters. Download: Download high-res image (186KB) Download: Download full-size image