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[Display omitted] • UiO-66-Rd i-s and UiO-66-Rd p-m adsorbents were designed for capturing Ag(I) from wastewater. • Rhodanine groups were confirmed to be modified outside of UiO-66-Rd p-m and inside of UiO-66-Rd i-s. • UiO-66-Rd p-m exhibited faster kinetic and higher selectivity for Ag(I) capture than UiO-66-Rd i-s. • Enhanced selectivity was dominated by high-exposure rhodanine sites outside of UiO-66-Rd p-m. Highly efficient capturing of silver from wastewater is critical for environmental and economic sustainability but remains significantly challenging to achieve fast kinetics and precise selectivity. Herein, we present two approaches based on rhodanine (Rd)-modified UiO-66 including post-modified ligand exchange for UiO-66-Rd p-m and in-situ solvothermal for UiO-66-Rd i-s. The resultant UiO-66-Rd p-m and UiO-66-Rd i-s perform maximum adsorption capacity of 120 and 109 mg·g−1, respectively, which are both about 6 times higher than pristine UiO-66. Benefitting from high-exposure Rd groups over the surface, UiO-66-Rd p-m exhibits about 3 times faster kinetic adsorption and nearly 15 times higher maximum selectivity coefficient than UiO-66-Rd i-s. Experiment and calculation demonstrate that the excellent performance of Rd-modified UiO-66 is dominantly owing to S chelation in the Rd group. In addition, site energy distributions of the Dubinin-Ashtakhov isotherm model confirm that UiO-66-Rd p-m has more effective sites for Ag(I) adsorption relative to UiO-66-Rd i-s. While a higher density of Rd outside the UiO-66-Rd p-m provides a larger coordination number of S/Ag (1.41) than UiO-66-Rd i-s (0.59), which is attributed to its sufficient exposed active S sites for multidentate coordination of Ag(I), thus significantly enhancing adsorption rate and selectivity. These findings are exploited to shed new insight into the design of adsorbents for the efficient recycling of noble metals from water. [ABSTRACT FROM AUTHOR]

• UiO-66-NH 2 -Rd adsorbent with dual coordination sites was designed and synthesized. • UiO-66-NH 2 -Rd exhibited high capacity and outstanding selectivity for Ag(I) capture. • Amide bonds endowed UiO-66-NH 2 -Rd with excellent recyclability and durability. • Specific adsorption site was identified by theoretical and experimental studies. Selective capture and maximum recovery of Ag(I) from wastewater is of great significance for a sustainable future. In this work, novel rhodanine (Rd)-functionalized UiO-66 adsorbents (i.e., UiO-66-Rd and UiO-66-NH 2 -Rd) were designed and synthesized. Different from previously reported UiO-66 derivatives with single metal coordination sites, the as-synthesized UiO-66-Rd and UiO-66-NH 2 -Rd have dual coordination sites, resulting in higher capacity and outstanding selectivity. The maximum capacities of UiO-66-Rd and UiO-66-NH 2 -Rd are 112 and 163 mg·g−1, nearly 5.6 and 8.2 times higher than that of UiO-66, respectively. Impressively, the maximum selectivity coefficient of UiO-66-NH 2 -Rd is approximately 1795 and 1173 folds higher than that of UiO-66 and UiO-66-NH 2. The experimental characterizations and theoretical calculations indicate that the Rd-induced enhancement in the adsorptivity and selectivity are mainly attributed to the dual coordination sites (i.e., C S and C S bonds), which collectively coordinate with Ag(I) in the form of Ag mono-coordinated with S. Compared with the UiO-66-Rd, UiO-66-NH 2 -Rd possesses excellent recyclability and durability due to the vital role of amide bonds generated from NH 2 group in the functionalization of UiO-66 with Rd. Furthermore, UiO-66-NH 2 -Rd can almost completely remove Ag(I) from the actual wastewater with complex matrix, satisfying the national integrated wastewater discharge standard and industrial wastewater emission standard, highlighting a great potential of practical application. [ABSTRACT FROM AUTHOR]