Synergy of first-and second-sphere interactions in a covalent organic framework boosts highly selective platinum uptake  

作　　者：Linwei He Baoyu Li Zhonglin Ma Lixi Chen Shicheng Gong Mingxing Zhang Yaoyao Bai Qi Guo Fuqi Wu Fuqiang Zhao Jie Li Duo Zhang Daopeng Sheng Xing Dai Long Chen Jie Shu Zhifang Chai Shuao Wang 

机构地区：[1]State Key Laboratory of Radiation Medicine and Protection,School for Radiological and Interdisciplinary Sciences(RAD-X)and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions,Soochow University,Suzhou 215123,China [2]Analysis and Testing Center,Soochow University,Suzhou 215123,China

出　　处：《Science China Chemistry》2023年第3期783-790,共8页中国科学（化学英文版）

基　　金：supported by the National Natural Science Foundation of China (21825601, 21790374, U1967217, 21906116, 22176139, 21906114);the National Key R&D Program of China (2018YFB1900203);the Postgraduate Research & Practice Innovation Program of Jiangsu Province (KYCX22_3212);the Postdoctoral Science Foundation of China (2021M692346, 2021M702390);the Foundation of Science and Technology on Surface Physics and Chemistry Laboratory (WDZC202102)

摘　　要：Platinum recovery from waste electrical and electronic equipment(WEEE) in highly acidic solutions is significant to the electronics industry and environmental remediation. However, the lack of ingenious design and synergetic coordination gives rise to unsatisfied PtCl_(4)^(2-)extraction capacities and selectivities in most previously reported adsorbents(e.g., polymeric and inorganic materials). Herein, we proposed a synergistic strategy that realizes highly selective PtCl_(4)^(2-)uptake through first-and second-sphere coordinations. The proof-of-concept imine-linked covalent organic framework(SCU-COF-3) was found to chelate Pt Cl42-via the direct N…Pt coordination and the synergistically interlaminar N–H…Cl hydrogen bonds, which was disclosed by the comprehensive analysis of extended X-ray adsorption fine structure(EXAFS) characterizations and density functional theory(DFT) calculations. The unique adsorption mechanism imparts a superior adsorption capacity(168.4 mg g-1)and extraordinary Pt(II) selectivity to SCU-COF-3 under static conditions. In addition, SCU-COF-3 exhibits an upgraded distribution coefficient of 1.62 × 10^(5)mL· g^(-1), one order of magnitude higher than those of reported natural adsorbents. Specifically, SCU-COF-3 can extract PtCl_(4)^(2- )quantitatively from a simulated acidic waste solution coexisting with other 12 competitive ions, suggesting its promising application in practical scenarios.

关 键 词：covalent organic frameworks PLATINUM hydrogen bond adsorption 

分 类 号：O64[理学—物理化学]