Yang Qian, Li Zehao, Chen ChengCheng, Zhang Zhengguo, Fang Xiaoming
Key Laboratory of Enhanced Heat Transfer and Energy Conservation, The Ministry of Education, School of Chemistry and Chemical Engineering, South China University of Technology Guangzhou 510640 China
Guangdong Engineering Technology Research Center of Efficient Heat Storage and Application, South China University of Technology Guangzhou 510640 China.
RSC Adv. 2019 Feb 5;9(8):4404-4414. doi: 10.1039/c8ra09576k. eCollection 2019 Jan 30.
Numerous vertical slices with thicknesses in the range of 100-200 nm were generated from pristine bulk carbon nitride (BCN) an ammonium nitrate (NHNO)-assisted hydrothermal treatment. Compared with the structure of BCN, the obtained novel hierarchical structure consisted of more uniform mesopores (2-14 nm) and possessed enlarged specific surface area of 64.1 m g. It was elucidated that both NH and NO play important roles in the formation of the vertical slices, which could not only create an acidic environment for the hydrothermal system but also form hydrogen bonds with the surface tri--triazine units of BCN simultaneously. It was found that the hierarchical structure exhibited enhanced crystallinity, reduced photoluminescence emission, and increased photocurrent response. Consequently, a hydrogen evolution rate of 1817.9 μmol h g was achieved by the hierarchical structure, which was 4.1 times higher than that of BCN. The hydrothermal post-treatment strategy explored in this work provides a new insight into the design and modification of polymeric carbon nitride for generating a hierarchical porous microstructure.
通过硝酸铵（NH₄NO₃）辅助水热法从原始块状氮化碳（BCN）制备了许多厚度在100 - 200纳米范围内的垂直薄片。与BCN的结构相比，所获得的新型分级结构由更均匀的中孔（2 - 14纳米）组成，比表面积增大至64.1平方米/克。研究表明，NH₄⁺和NO₃⁻在垂直薄片的形成中都起着重要作用，它们不仅能为水热体系创造酸性环境，还能同时与BCN表面的三嗪单元形成氢键。结果发现，这种分级结构具有增强的结晶度、降低的光致发光发射和增加的光电流响应。因此，这种分级结构实现了1817.9微摩尔/小时·克的析氢速率，是BCN的4.1倍。这项工作中探索的水热后处理策略为聚合物氮化碳的设计和改性提供了新的思路，以生成分级多孔微结构。
