近日，中南民族大学吕康乐团队实现了通过K⁺掺杂和氰化物缺陷工程提高结晶g-C₃N₄对NO氧化和CO₂还原的光催化活性。该研究于2025年8月6日发表于《结构化学》杂志上。

聚合物半导体光催化剂石墨氮化碳（g-C₃N₄）因其可见光响应性和良好的生物相容性而受到广泛关注。

然而，由于本体g-C₃N₄ （CNB）的光吸收范围有限，载流子重组速度快，因此其光催化效率在实际应用中仍然不足。研究组在KCl存在下，采用双氰胺煅烧法制备了含氰缺陷的K⁺掺杂g-C₃N₄晶体（CNK）。KCl的加入促进了含氰缺陷的K⁺掺杂g-C₃N₄晶体的形成。优化后的光催化剂CNK₂对NO氧化的光催化活性最高，去除率达47.40%，是CNB的2.1倍。这种增强主要是由于活性氧（ROS）的产生增加，特别是超氧自由基（O₂^-）和单线态氧（¹O₂）。

此外，还观察到光催化CO₂-to-CH₄转化性能的提高，这是由于K⁺离子掺杂引起的内建电场（BIEF）的形成和氰基缺陷的引入。

附：英文原文

Title: Enhancing the photocatalytic activity of crystalline g-C3N4 towards NO oxidation and CO2 reduction through K+-doping and cyano defects engineering

Author: anonymous

Issue&Volume: 2025-08-06

Abstract: The polymeric semiconductor photocatalyst graphitic carbon nitride (g-C3N4) has attracted considerable attention due to its visible-light responsiveness and excellent biocompatibility. However, the photocatalytic efficiency of bulk g-C3N4 (CNB) remains insufficient for pratical applications, primarily due to its limited light absorption range and the rapid charge carrier recombination. In this study, K+-doped crystalline g-C3N4 with cyano defects (CNK) was synthesized by the calcination of dicyandiamide in the presence of KCl. The addition of KCl promoted the formation of K+-doped crystalline g-C3N4 with cyano defects. The optimized photocatalyst (CNK2) exhibited the highest photocatalytic activity for NO oxidation, achieving a removal rate of 47.40%, which is 2.1 times higher than that of CNB. This enhancement is mainly attributed to the increased generation of reactive oxygen species (ROS), particularly superoxide radicals (O2-) and singlet oxygen (1O2). Furthermore, improved performance in photocatalytic CO2-to-CH4 conversion was also observed, which is attributed to the formation of a build-in electric field (BIEF) induced by K+ ion doping and the introduction of cyano defects.

DOI: 10.1016/j.cjsc.2025.100698

Source: http://cjsc.ac.cn/cms/issues/852