The　selective　capture　of　low-concentration　CO2　from　air　or　confined　spaces　remains　a　great　challenge.　In　this　study,　various　functional　groups　were　introduced　into　UiO-66　to　generate　functionalized　derivatives　(UiO-66-R,　R　=　NO2,　NH2,　OH,　and　CH3),　aiming　at　significantly　enhancing　CO2　adsorption　and　separation　efficiency.　More　significantly,　UiO-66-NO2　and　UiO-66-NH2　with　high　polarity　exhibit　exceptional　CO2　affinity　and　optimal　separation　characteristics　in　mixed　CO2/O2/N2　(1:21:78).　In　addition,　the　impressive　stability　of　UiO-66-NO2　and　UiO-66-NH2　endows　them　with　excellent　recycling　stability.　The　effective　adsorption　and　separation　performances　demonstrated　by　these　two　functional　materials　suggest　their　potential　as　promising　physical　adsorbents　for　capturing　low-concentration　CO2.　©　2023　American　Chemical　Society.