Photocatalytic production of hydrogen peroxide (HO) from O and water offers a sustainable and environmentally friendly approach to solar-to-chemical energy conversion. To address the low HO yield of pristine carbon quantum dots (CQDs) (354 µmol g h), we applied molecular level engineering of CQDs through surface NH functionalization (CQDs-NH), which significantly increased photocatalytic activity of HO production to 2974 µmol g h. This enhanced performance is attributed to the CN-NH- group in CQDs-NH, which improves light absorption, facilitates carrier separation and transfer, increases the selectivity of two-electron oxygen reduction reaction, and promotes oxygen adsorption. Additionally, the hydrogen atom in the CN-NH- group acts as a proton conductor, which significantly promoted the proton-coupled electron transfer process to produce HO in the presence of O. Moreover, a high HO production capacity of 2764 µmol g h was obtained even in the absence of an electron donor.

中文翻译：

---

用于高效光催化过氧化氢生产的表面工程碳量子点

利用 O 和水光催化生产过氧化氢 (H2O) 为太阳能转化为化学能提供了一种可持续且环保的方法。为了解决原始碳量子点 (CQD) (354 µmol g h) 的低 H2O 产量问题，我们通过表面 NH 功能化 (CQDs-NH) 应用 CQD 的分子水平工程，将 H2O 生产的光催化活性显着提高至 2974 µmol g h 。这种增强的性能归功于CQDs-NH中的CN-NH-基团，它提高了光吸收，有利于载流子分离和转移，增加了双电子氧还原反应的选择性，并促进了氧吸附。此外，CN-NH-基团中的氢原子充当质子导体，显着促进了在O存在下产生H2O的质子耦合电子转移过程。此外，获得了2764 µmol gh的高H2O生产能力即使没有电子供体。