A CuCo Bimetal Confined Hollow SiC Hybrid Photothermal Nanoreactor for the Integration of Pollutant Mineralization and Solar-Powered Water Evaporation

Abstract

Growing attention has been paid to the rational treatment of antibiotics-bearing medical wastewater. However, the complexity of polluted wastewater makes the later comprehensive treatment difficult only by the Advanced Oxidation Process technique. Therefore, the coupled water treatment techniques including contaminant mineralization and regeneration of cleanwater become very attractive. A bimetallic functional hollow nanoreactor defined as (Co@SiO₂/Cu−X) was successfully constructed by coating a Cu-doped silica layer on the metal-organic framework (ZIF-67) followed by programmed calcination in nitrogen. The nanoreactor was endowed with a hollow configuration composed of mesoporous N-doping C-Silica hybrid shell encapsulated ultrafine Cu and Co metallic species. Such a configuration allows for the efficient diffusion and open reaction space of big contaminant molecules. The catalytic synergy of exposed Co−Cu bimetals and the easy accessibility of electron-rich contaminants by polar N doping sites triggered surface affinity make the optimal Co@SiO₂/Cu-6 afford an excellent catalytic norfloxacin mineralization activity (7 min, k_abs=0.744 min⁻¹) compared to Cu-free Co@SiO₂-6 (k_abs=0.493 min⁻¹) and Co-6 (k_abs=0.378 min⁻¹) Benefiting from the above unique advantages, Co@SiO₂/Cu-6 show excellent removal performance in degrading different pollutants (carbamazepine, oxytetracycline, tetracycline, and bisphenol A) and persistent recycled stability in removing NFX. In addition, by virtue of the excellent photothermal properties, interfacial solar water evaporation application by Co@SiO₂/Cu-6 was further explored to reach the regeneration of cleanwater (1.595 kg m⁻² h⁻¹, 97.51 %). The integration of pollutant mineralization and solar water evaporation by creating the monolith evaporation by anchoring the Co@SiO₂/Cu-6 onto the tailored melamine sponge allows the regeneration of cleanwater (1.6 kg⋅m⁻²⋅h⁻¹) and synchronous pollutant removal (NFX, 95 %, 60 min), which provides potential possibility the treatment of complicated wastewater.