College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, Guangdong, 518060, P. R. China.
Institute of Information Technology, Shenzhen Institute of Information Technology, Shenzhen, Guangdong, 518172, P. R. China.
Adv Sci (Weinh). 2022 Jul;9(21):e2201677. doi: 10.1002/advs.202201677. Epub 2022 Jun 2.
Most near-infrared (NIR) light-responsive photocatalysts inevitably suffer from low charge separation due to the elevated Coulomb interaction between electrons and holes. Here, an n-type doping strategy of alkaline earth metal ions is proposed in crystalline K implanted polymeric carbon nitride (KCN) for visible and NIR photoactivity. The n-type doping significantly increases the electron densities and activates the n→π* electron transitions, producing NIR light absorption. In addition, the more localized valence band (VB) and the regulation of carrier effective mass and band decomposed charge density, as well as the improved conductivity by 1-2 orders of magnitude facilitate the charge transfer and separation. The proposed n-type doping strategy improves the carrier mobility and conductivity, activates the n→π* electron transitions for NIR light absorption, and breaks the limitation of poor charge separation caused by the elevated Coulomb interaction.
大多数近红外（NIR）光响应光催化剂由于电子和空穴之间的升高库仑相互作用不可避免地遭受低电荷分离。在这里，提出了在晶态 K 注入聚合物碳氮化物（KCN）中进行碱土金属离子的 n 型掺杂策略，以实现可见光和 NIR 光活性。n 型掺杂显著增加了电子密度，并激活了 n→π电子跃迁，产生了 NIR 光吸收。此外，更局域的价带（VB）和载流子有效质量以及能带分解电荷密度的调节，以及通过 1-2 个数量级提高的电导率，有利于电荷转移和分离。所提出的 n 型掺杂策略提高了载流子迁移率和电导率，激活了 n→π电子跃迁以吸收 NIR 光，并打破了由于升高的库仑相互作用而导致的电荷分离不良的限制。
