International water security has become unprecedentedly complicated, therefore, effective and selective removal of hazardous materials, especially toxic heavy metal ions, are significant for effluent purification. In this regard, ion-imprinted polymers with special recognition cavities have received much attention. However, configuration screening and performance optimization of functional materials by trial-and-error design method is undoubtedly time- and money-consuming. In this study, high-performance ion-imprinted chitosan microspheres (ICSMs) were successfully designed via density functional theory (DFT) calculation and synthesized via facile microfluidic technology. As-synthesized ICSMs exhibited highly uniform morphology (Dav = 420.6 µm, CV = 3.6%) and ultra-high adsorption capacity (qmax = 107.12 mg g−1). The adsorption isotherm was best fitted to the Langmuir model while the kinetic data followed the pseudo-second order model, indicating a dominant role of chemisorptions. Also, ICSMs displayed satisfactory stability and reusability (95.34 mg g−1, after 5 cycles). Moreover, the selective adsorption mechanism was quantitative revealed by electronegativity, electrophilicity index, adsorption energy (Ea) and bond length. This study is expected to lay a foundation for high-performance biosorbents design and synthesis for future water remediation
