In this work, nitrogen doped g-C₃N₄ (NCN) with the extremely narrow band gap was prepared and applied for the photodegradation of phenols. Experiments and DFT (the density functional theory) computation identified that N-doping introduced in the g-C₃N₄ matrix by substituting C atoms. DFT, PL (photoluminescence) spectra, optical property characteristic and PEC (photoelectrochemical) indicated that NCN possess extremely narrow band gap, efficient photogenerated carrier separation and the charge transfer, which enhanced the absorption of visible light and further promoted the photocatalytic activity. As a result, NCN(2:2) showed about twice higher photodegradation efficiencies and 3 times rate constant than pristine g-C₃N₄. The radical trapping experiments showed that •O₂- radical and h⁺ served as crucial active species during the whole photodegradation reaction. This work can provide a strategy to enhance the photocatalytic activity of photocatalysts via introduce foreign atoms in matrix.

在这项工作中，制备了带隙极窄的氮掺杂gC ₃ N ₄（NCN），并将其用于苯酚的光降解。实验和DFT（密度泛函理论）计算确定，通过取代C原子，在gC ₃ N ₄矩阵中引入了N掺杂。DFT，PL（光致发光）光谱，光学特性和PEC（光电化学）表明，NCN具有极窄的带隙，有效的光生载流子分离和电荷转移，这增强了可见光的吸收并进一步促进了光催化活性。结果，NCN（2：2）的光降解效率是原始gC _3的两倍，速率常数是其三倍。N ₄。自由基捕获实验表明，•O _2-自由基和h ⁺在整个光降解反应中起着至关重要的活性作用。这项工作可以提供一种通过在基质中引入外来原子来增强光催化剂的光催化活性的策略。