2026-10-11T19:54:16Z https://www.scidb.cn/oai

10.57760/sciencedb.37609 2026-05-21T13:59:52Z

2026-05-21 Activating inert cobalt sites via interfacial nitrogen vacancies in Co3O4@g-C3N4 heterojunctions for selective boron recovery from hypersaline brines doi:10.57760/sciencedb.37609 en Abstract Developing efficient adsorbents for selective boron capture remains fundamentally challenging due to two distinct barriers: the weak binding affinity of neutral boric acid (H3BO3) and severe competitive interference from coexisting ions in complex water matrices. Although transition metal oxides offer theoretical potential for boron coordination, their practical performance is severely restricted by particle agglomeration and insufficiently activated surface metal sites. To overcome these bottlenecks, we report a heterojunction adsorbent (CoCN) constructed by coupling nitrogen-vacancy-rich ultrathin g-C3N4 nanosheets with ZIF-67-derived porous Co3O4. Batch adsorption experiments combined with density functional theory (DFT) calculations reveal that interfacial nitrogen vacancies act as electron sinks, inducing pronounced charge redistribution that renders adjacent Co sites more electron-deficient. This electronic modulation enhances their Lewis acidity, lowers the adsorption free energy (ΔG = -4.28 eV), and facilitates the spontaneous formation of robust Co-O-B coordination bonds. Consequently, the optimized CoCN-5 delivers an equilibrium boron adsorption capacity of 128.5 mg g-1 at 25 °C within 120 min, significantly outperforming pristine Co₃O₄ (~8.2 mg g-1). Furthermore, the material demonstrates exceptional practical viability in actual hypersaline brines (LaGuoCuo: 81 mg g-1; ChaErHan: 79 mg g-1), achieving remarkably high separation factors against major competing ions (SF(B/Na) = ~217, SF(B/Mg) = ~159). These findings establish interfacial defect engineering as a precise strategy for activating metal oxide sites, providing a molecular-level paradigm for selective boron recovery from complex aquatic systems. Boron adsorption; Defect engineering; Electronic modulation; Lewis acid-base interaction; Complex aqueous systems 邵一凡 柳瑞瑞 潘建明 周永全 EMBARGO https://creativecommons.org/licenses/by-nc-nd/4.0/ dataset Science Data Bank