Breaking the Limitation of Elevated Coulomb Interaction in Crystalline Carbon Nitride for Visible and Near‐Infrared Light Photoactivity
Guoqiang Zhang, Yangsen Xu, Muhammad Rauf, Jinyu Zhu, Yongliang Li, Chuanxin He, Xiangzhong Ren, Peixin Zhang, Hongwei Mi
Abstract
Abstract 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.