Mingmei Zhang

While silver halides (AgX) are promising visible-light photocatalysts for water remediation, their practical deployment is severely hindered by intrinsic photocorrosion, rapid charge recombination, and macroscopic recovery challenges. Here, we demonstrate a monolithic AgX/biomass carbon aerogel composite platform, constructed by anchoring AgX nanocrystals in situ onto a 3D hierarchical carbon skeleton. The carbon network not only suppresses nanoparticle aggregation but also plays contrasting optical roles: amplifying the intrinsic visible-light absorption of AgBr while endowing the otherwise UV-confined AgCl with substantial visible-light response. Consequently, the optimal 30 wt% AgBr/CA composite achieves a 95.68% methylene blue degradation efficiency within 60 min—outperforming pristine AgBr by 2.6-fold—while establishing robust activity against two additional, structurally distinct pollutants: rhodamine B and the colorless antibiotic ciprofloxacin. Notably, the free-standing monolith retains exceptional activity over six consecutive cycles. Mechanistic investigations reveal that the carbon aerogel functions as an electron-accepting reservoir, which accelerates interfacial charge separation and steers electron flow toward superoxide radical generation. Notably, XRD and XPS analyses confirm that no detectable metallic Ag⁰ is present in the as-prepared composites. This work establishes a sustainable and scalable architectural paradigm for designing highly efficient, stable, and easily recyclable photocatalytic systems.

Low-temperature dried alginate/silica hybrid aerogel beads with a large specific surface area (160.8 m²/g), low density (0.160 m²/g), and high degree of sphericity were successfully fabricated. Single networks of silica aerogels beads were synthesized via by calcining hybrid aerogel beads in air. Moreover, alginate-derived carbon/silica aerogel beads were also obtained by the thermal treatment of the hybrid aerogel beads in nitrogen, which were indicative of the double networks of the as-synthesized crack-free hybrid aerogel beads for the first time. The adsorption performances of above aerogel beads were also investigated. Meanwhile, using a common silane coupling agent as a modifying agent, a series of hybrid aerogel beads with tunable functional surfaces were obtained. The results showed that the obtained samples adsorbed Pb²⁺ well, and the hybrid aerogel beads modified with KH-590 exhibited an experimental maximum adsorption capacity of Pb²⁺ of 193.73 mg·g⁻¹.