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.

可持续的分离技术是获得高纯度单色荧光碳量子点（CQD）的关键，而高纯度单色荧光碳量子点在发光二极管，生物成像和生物医学中具有广泛的潜在应用。在这项工作中，首次展示了一种绿色，持久且通用的方法，该方法使用纯水作为洗脱液有效分离大量亲水性混合轻质CQD。一次分离后，根据CQD尺寸的增加，可以将多色荧光CQD分为两个，三个和四个CQD，在紫外线照射下，荧光色的梯度从蓝色到橙色。分离前CQD的荧光颜色的红移越大，分离后获得的荧光CQD的数量越多。与多色CQD相比，分离的CQD显示出相似的结构特征，更高的色纯度，更窄的半峰全宽以及更好的与激发无关的性能。这种分离策略依赖于吸附容量-尺寸效应。我们的发现为使亲水性轻质混合轻质CDD分离变得实用而直接敞开了大门，这将扩大亲水性CQD的潜在应用。