2D covalent organic framework-based core-shell structures for high-performance solar-driven steam generation

2D covalent organic frameworks (COFs) are a promising candidate in the field of solar-driven steam generation (SSG), though their applications are limited by the narrow-band spectral response, complicated framework design, expensive building blocks, and weak chemical stability in current stage. Herein, a composite photothermal material TpPa-COF@MoS 2 (MoCOF) with a core-shell structure is prepared by encapsulation of the MoS 2 micron-flowers with TpPa-COF via in situ growth to relieve the aforementioned shortcomings. Interestingly, the as-synthesized MoCOF not only presents an enhanced photothermal performance (78.5 °C, at 1 sun intensity) but also has a relative lower cost. Afterwards, a MoCOF@Gel SSG evaporator is fabricated by introducing MoCOF composites into the PVA (polyvinyl alcohol) polymer network . Attributing to the synergistic effects of efficient heat localization, hierarchical water pathways, and hydrophilic channels with a large specific surface area, the MoCOF@Gel shows a high evaporation rate up to 2.31 kg/m 2 /h and energy efficiency of 91.8% under one sun irradiation, which is superior to most of reported COF based steam generators. Furthermore, the MoCOF@Gel also shows robust mechanical property, satisfactory purification performance, and exceptionally antibacterial activity.