Dou Qian, Hou Jianhua, Hussain Asif, Zhang Geshan, Zhang Yongcai, Luo Min, Wang Xiaozhi, Cao Chuanbao
College of Environmental Science and Engineering, Yangzhou University, Yangzhou 225000, PR China.
College of Environmental Science and Engineering, Yangzhou University, Yangzhou 225000, PR China; Guangling College, Yangzhou University, Yangzhou 225009, PR China; Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing 210095, PR China.
J Colloid Interface Sci. 2022 Oct 15;624:79-87. doi: 10.1016/j.jcis.2022.05.085. Epub 2022 May 17.
Graphitic carbon nitride (g-CN) is considered as a promising low-cost polymeric semiconductor as conjugated photocatalyst for energy and environmental application. This study exhibits a Na-doped g-CN with willow-leaf-shaped structure and high degree of crystallinity, which was synthesized with a convenient thermal polymerization using sodium carbonate (NaCO) as the sodium source. The π-conjugated systems of g-CN were improved by doping sodium, which could accelerate the electron transport efficiency resulting in outstanding photocatalytic properties. Furthermore, optimum Na-doped g-CN (CN-0.05) attributed its enhanced irradiation efficiency of light energy to its narrower band gap and significant improvement in charge separation. Consequently, the H evolution rate catalyzed with CN-0.05 can achieve 3559.8 μmol g h, which is about 1.9 times higher than that with pristine g-CN. The rate of CN-0.05 for reduction of CO to CO (3.66 μmol g h) is 6.6 times higher than that of pristine g-CN. In experiments of pollutants degradation, the reaction constants of degradation of rhodamine B (RhB) and methyl orange (MO) with CN-0.05 were 0.0271 and 0.0101 min, respectively, which are 4.7 and 7.2 times more efficient than pristine g-CN, respectively. This work provides a simple preparation method for tailoring effective photocatalyst for the sustainable solution of environmental issues.
石墨相氮化碳（g-CN）被认为是一种很有前景的低成本聚合物半导体，可作为用于能源和环境应用的共轭光催化剂。本研究展示了一种具有柳叶状结构和高结晶度的钠掺杂g-CN，它是使用碳酸钠（Na₂CO₃）作为钠源通过简便的热聚合反应合成的。通过掺杂钠改善了g-CN的π共轭体系，这可以加速电子传输效率，从而产生出色的光催化性能。此外，最佳的钠掺杂g-CN（CN-0.05）将其光能辐照效率的提高归因于其更窄的带隙和电荷分离的显著改善。因此，CN-0.05催化的析氢速率可达3559.8 μmol g⁻¹ h⁻¹，约为原始g-CN的1.9倍。CN-0.05将CO₂还原为CO的速率（3.66 μmol g⁻¹ h⁻¹）是原始g-CN的6.6倍。在污染物降解实验中，CN-0.05降解罗丹明B（RhB）和甲基橙（MO）的反应常数分别为0.0271和0.0101 min⁻¹，分别比原始g-CN高效4.7倍和7.2倍。这项工作为定制有效的光催化剂以可持续解决环境问题提供了一种简单的制备方法。
