Structural Investigation of Graphitic Carbon Nitride via XRD and Neutron Diffraction
Structural Investigation of Graphitic Carbon Nitride via XRD and Neutron Diffraction
复制标题
DOI：
10.1021/acs.chemmater.5b00411
复制
发表时间：
2015-04-14
影响因子：
8.6
通讯作者：
Irvine, John T. S.
中科院分区：
文献类型：
--
作者：
Fina, Federica;Callear, Samantha K.;Irvine, John T. S.
自2009年以来，石墨氮化碳（g-C3N4）作为一种可见光活性的析氢光催化剂引起了人们的广泛关注。自1834年合成以来，g-C3N4在催化和结构上都得到了广泛的研究。虽然它的二维结构似乎已经解决了，但它的三维晶体结构尚未得到证实。本研究尝试用x射线衍射和中子散射的方法求解石墨氮化碳的三维结构。首先，考虑了各种结构模型，并将其XRD谱图与实测模型进行了比较。在选择了g-C3N4等可能的候选结构后，利用中子散射技术确定了描述石墨氮化碳三维结构的最佳模型。发现以AB堆叠基序分层组织的三-s-三嗪单元的平行链很好地描述了合成的石墨氮化碳的结构。层间的不对齐是有利的，因为层间的pp排斥相互作用减少了。
Graphitic carbon nitride (g-C3N4) has, since 2009, attracted great attention for its activity as a visible-light-active photocatalyst for hydrogen evolution. Since it was synthesized in 1834, g-C3N4 has been extensively studied both catalytically and structurally. Although its 2D structure seems to have been solved, its 3D crystal structure has not yet been confirmed. This study attempts to solve the 3D structure of graphitic carbon nitride by means of X-ray diffraction and of neutron scattering. Initially, various structural models are considered and their XRD patterns compared to the measured one. After selecting possible candidates as g-C3N4 structure, neutron scattering is employed to identify the best model that describes the 3D structure of graphitic carbon nitride. Parallel chains of tri-s-triazine units organized in layers with an AB stacking motif are found to describe the structure of the synthesized graphitic carbon nitride well. A misalignment of the layers is favorable because of the decreased pp repulsive interlayer interactions.