A　sustainable　separation　technique　is　a　key　to　obtaining　high-purity　monochrome　fluorescent　carbon　quantum　dots　(CQDs),　which　have　broad　potential　applications　in　light-emitting　diodes,　bioimaging,　and　biomedicine.　In　this　work,　a　green,　tenable,　and　universal　method　of　effectively　separating　a　large　number　of　hydrophilic　hybrid-light　CQDs　using　pure　water　as　the　eluent　was　demonstrated　for　the　first　time.　Just　after　one　separation,　multicolor　fluorescent　CQDs　can　be　divided　into　two,　three,　and　four　CQDs　with　a　gradient　of　fluorescent　colors　ranging　from　blue　to　orange　under　UV　light　irradiation,　in　accordance　with　the　increasing　size　of　CQDs.　The　larger　red-shift　of　the　fluorescent　color　of　CQDs　before　separation,　the　more　the　quantity　of　fluorescent　CQDs　were　obtained　after　separation.　Comparing　with　multicolor　CQDs,　the　separated　CQDs　reveal　similar　structure　characteristics,　higher　color-purity,　narrower　full　width　at　half　maximum,　and　better　excitation-independent　performance.　This　separation　strategy　relies　on　the　adsorption　capacity-size　effect.　Our　finding　opens　the　door　to　make　separating　hydrophilic　hybrid-light　CQDs　practical　and　straightforward,　which　will　expand　the　potential　applications　of　hydrophilic　CQDs.　(C)　2019　Published　by　Elsevier　Ltd.