State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, China.
Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, 10691, Sweden.
Nat Commun. 2023 Jan 17;14(1):263. doi: 10.1038/s41467-023-35971-w.
The role of N-heterocyclic carbene, a well-known reactive site, in chemical catalysis has long been studied. However, its unique binding and electron-donating properties have barely been explored in other research areas, such as metal capture. Herein, we report the design and preparation of a poly(ionic liquid)-derived porous organic polycarbene adsorbent with superior gold-capturing capability. With carbene sites in the porous network as the "nanotrap", it exhibits an ultrahigh gold recovery capacity of 2.09 g/g. In-depth exploration of a complex metal ion environment in an electronic waste-extraction solution indicates that the polycarbene adsorbent possesses a significant gold recovery efficiency of 99.8%. X-ray photoelectron spectroscopy along with nuclear magnetic resonance spectroscopy reveals that the high performance of the polycarbene adsorbent results from the formation of robust metal-carbene bonds plus the ability to reduce nearby gold ions into nanoparticles. Density functional theory calculations indicate that energetically favourable multinuclear Au binding enhances adsorption as clusters. Life cycle assessment and cost analysis indicate that the synthesis of polycarbene adsorbents has potential for application in industrial-scale productions. These results reveal the potential to apply carbene chemistry to materials science and highlight porous organic polycarbene as a promising new material for precious metal recovery.
N-杂环卡宾作为一种众所周知的反应活性位点，其在化学催化中的作用早已得到广泛研究。然而，其独特的配位和供电子性质在金属捕获等其他研究领域几乎尚未得到探索。在此，我们报告了一种具有优越金捕获能力的聚（离子液体）衍生多孔有机聚卡宾吸附剂的设计和制备。多孔网络中的卡宾位点作为“纳米陷阱”，其金捕获容量高达 2.09 g/g。在电子废物提取溶液中复杂金属离子环境的深入探索表明，聚卡宾吸附剂具有 99.8%的高金回收效率。X 射线光电子能谱和核磁共振波谱表明，聚卡宾吸附剂的高性能源于形成了稳定的金属-卡宾键以及将附近的金离子还原成纳米颗粒的能力。密度泛函理论计算表明，多核 Au 结合的能量有利增强了吸附作用。生命周期评估和成本分析表明，聚卡宾吸附剂的合成具有在工业规模生产中应用的潜力。这些结果表明卡宾化学在材料科学中的应用潜力，并突出了多孔有机聚卡宾作为一种有前途的新型贵金属回收材料。
