The photocatalytic performance of carbon dots is strongly related to surface modifications and graphitization. Herein, we show that carbon dots without metal loaded can serve as an efficient photocatalyst for reducing CO₂. The conjugate carbon great π could stabilize the photogenerated electrons, which turned out to improve the separation of the photogenerated electron-hole pairs and can kinetically promote interfacial reaction. Besides, the strong chemisorption of the nitrogen-containing groups on the carbon dots to the CO would help to further conversion of the intermediate in the demonstrated CO₂ photo-reduction systems. As a result of these merits, the highly graphitized carbon dots prepared from graphene oxide with plenty of nitrogen-containing groups exhibit 74.8% electronic selectivity of methane. This strategy provides an important requirement for designing of CO₂ photocatalysts.

碳点的光催化性能与表面改性和石墨化密切相关。在本文中，我们表明没有负载金属的碳点可以用作减少CO ₂的有效光催化剂。π大的共轭碳可以稳定光生电子，从而改善了光生电子-空穴对的分离，并可以动力学地促进界面反应。此外，碳点上的含氮基团强烈地化学吸附到CO上将有助于进一步证明所展示的CO ₂中的中间体光还原系统。这些优点的结果是，由具有大量含氮基团的氧化石墨烯制备的高度石墨化的碳点表现出74.8％的甲烷电子选择性。该策略对设计CO ₂光催化剂提出了重要要求。