基于后功能化工艺修饰类石墨相氮化碳及其光催化产氢性能研究

Post-functionalization of graphitic carbon nitride for highly efficient photocatalytic hydrogen evolution

本研究设计了一种后功能化工艺方法修饰类石墨相氮化炭材料。通过此工艺成功得到了硼掺杂的介孔氮化炭材料,该材料比表面积高达125 m^(2)/g,这为提升光催化分解水性能奠定了基础。利用X射线衍射、X射线光电子能谱,荧光光谱和紫外-可见光谱对材料进行了全面的表征。基于X射线光电子能谱分析,发现通过后功能化处理硼原子成功掺杂进入氮化炭的晶格中;通过吸收光谱分析得知,硼掺杂的介孔氮化炭材料增强了在可见光区的光吸收;通过荧光光谱分析得知,相比原始氮化炭材料,硼掺杂后的介孔氮化炭材料有着更低的荧光强度,意味着光生电子和空穴的分离得到了提升。对材料进行光催化分解水测试,后功能化处理得到的硼掺杂介孔氮化炭材料的产氢速率是原始氮化炭材料的10.2倍。此结论对后续利用后功能化工艺修饰材料提升材料性能具有一定的借鉴意义。

In this work we report the feasible modification of graphitic carbon nitride(g-C_(3)N_(4))polymer through a post-functionalization progress.The resultant photocatalyst exhibits boron doping and mesoporous structure with a high surface area of 125 m^(2)/g,leading in an increased surface activity for photocatalytic water splitting reaction.X-ray diffraction,X-ray photoelectron spectroscopy,PL emission spectra and UV-Vis spectra were used to detect the properties of as-prepared samples.Based on X-ray photoelectron spectroscopy analysis,boron is proposed to dope in the g-C_(3)N_(4) lattice.Optical studies indicated that boron doped g-C_(3)N_(4) exhibits enhanced and extended light absorbance in the visible-light region and a much lower intensity of PL emission spectra compared to pure g-C_(3)N_(4).As a result,boron doped g-C_(3)N_(4) shows activity of 10.2 times higher than the pristine g-C_(3)N_(4) for photocatalytic hydrogen evolution.This work may provide a way to design efficient and mesoporous photocatalysts through post modification.