Ho Wingkei, Zhang Zizhong, Lin Wei, Huang Shuping, Zhang Xianwen, Wang Xuxu, Huang Yu
Department of Science and Environmental Studies, The Hong Kong Institute of Education , Hong Kong, China.
ACS Appl Mater Interfaces. 2015 Mar 11;7(9):5497-505. doi: 10.1021/am509213x. Epub 2015 Mar 2.
Copolymerization with 2,4,6-triaminopyrimidine (TAP) is developed for precise substitution of one nitrogen with carbon atom in the triazine ring of polymeric g-C3N4. Direct incorporation of C4N2 ring from TAP into the network retains the structural features of g-C3N4, but induces the rolling-up of g-C3N4 sheets into tubular configuration. The band gap energy is narrowed from 2.7 to 2.4 eV by a negative shift of valence band of the g-C3N4 photocatalyst, which enhances charge-carrier migration and separation, leading to higher photocatalytic activity for NO gas pollutant removal. It is attributed to the decrease of the π-deficiency and the generation of imbalanced electron density in π-electron conjugated units of g-C3N4 by TAP incorporation. This work provides a significant technique for precise control of heteroatom in the framework of g-C3N4 to finely adjust its intrinsic electronic properties and its photocatalytic properties.
与2,4,6-三氨基嘧啶（TAP）的共聚反应被用于在聚合石墨相氮化碳（g-C3N4）的三嗪环中精确地用碳原子取代一个氮原子。将TAP中的C4N2环直接并入网络中保留了g-C3N4的结构特征，但会导致g-C3N4片层卷曲成管状结构。g-C3N4光催化剂的价带负移使带隙能量从2.7 eV缩小到2.4 eV，这增强了电荷载流子的迁移和分离，从而对去除NO气体污染物具有更高的光催化活性。这归因于通过引入TAP，g-C3N4的π-缺电子性降低以及π-电子共轭单元中电子密度失衡的产生。这项工作为在g-C3N4框架中精确控制杂原子以精细调节其固有电子性质和光催化性质提供了一项重要技术。
