Integration of bimetallic CuCo into N-doping SiC hollow nanoreactor for pollutant removal coupled solar-driven cleanwater regeneration.

Photothermal nanomaterials have showed great potential for development in simultaneous pollutant purification and freshwater recovery. In this study, a novel composite composed of hollow N-doping SiC porous hybrid network with the integration of CoCu bimetal species was constructed by a simple self-assembly and temperature-modulated approach. Such a hollow porous hybrid nanoreactor is endowed with abundant synergetic CuCo bimetallic reactive sites and polar pyrrolic N sites, which improves the enrichment of pollutants and intermetallic redox pairs. Ultrafine nanocrystals corresponding to Co 2 SiO 4 over the hybrid framework can be evidenced by HRTEM technique. The experimental results showed that the optimal CoSiCu-6 degraded norfloxacin (NFX) by 90.7% in 10 min with a pseudo-first-order rate constant of 0.493 min⁻¹, which was about 6.49 folds enhancement compared to Cu-free CoSi-6 counterparts, achieving a low reaction activation energy (18.02 kJ mol⁻¹) during the reaction. Control experiments including anion interference and broad applicability for pollutants degradation were further explored, emphasizing the excellent performance of CoSiCu-6 in the practical contaminant removal. The mechanism study showed that, single linear oxygen (¹O 2) coupled with electron-transfer process work as the main activation routes dominating the degradation process. In addition, Co³⁺/Co²⁺/Cu²⁺ redox pairs and oxygen vacancies (O v) play a key role in the PMS activation process. The obtained optimal catalyst was further explored for solar-driven photothermal interfacial water evaporation, showing a rational cleanwater recovery efficiency (∼1.3 kg m⁻² h⁻¹) from the polluted wastewater. In addition, monolith floatable evaporator was constructed by anchoring CoSiCu-6 onto a tailored melamine sponge foam via a calcium ion-triggered sodium alginate cross-linking strategy, affording an excellent evaporation performance (2.16 kg m⁻² h⁻¹) and coupled norfloxacin degradation efficiency (93.6%, within 5 min). This innovative monolithic evaporator made of CoCu integrated SiC hybrid nanosphere has a powerful dual function of rapidly degrading pollutants and facilitating solar-powered regeneration of contaminated wastewater due to its unique hollow porous structure and the CoCu bimetallic synergistic action that provides a rich set of reaction sites, which is promising for the treatment of complicated wastewater. [Display omitted] • N-doping SiC hybrid hollow nanoreactor confined bimetallic CoCu species was constructed. • N-doping polar sites coupled nanochannel contribute to efficient enrichment and mass-transfer of contaminants. • Excellent mineralization of various persistent pollutants was enabled by obtained nanoreactor. • The monolith evaporator was constructed by anchoring nanoreactor onto melamine sponge. • The monolith evaporator enables synchronous pollutant mineralization and solar evaporation. [ABSTRACT FROM AUTHOR]