Abstract In this report, we demonstrate on the preparation of mesoporous graphitic carbon nitride (gCN) with 3D porous structure using dicyandiamide as a CN precursor and KIT-6 as a template via hard-template replication method and its superior photocatalytic hydrogen evolution activity under simulated sunlight. The powder X-ray diffraction, nitrogen adsorption and near edge X-ray absorption fine structure (NEXAFS) results reveal that the prepared materials possess gCN crystal structure with ordered mesopores and a 3D porous structure and a high specific surface area (221 m2/g). UV–Vis and PL spectra show that the absorption edges of mesoporous gCNs are slightly blue-shifted and the PL intensity is remarkably suppressed. The photocatalytic hydrogen evolution activity of gCN-KIT-6 under solar simulated irradiation is 1.92 mmol·g−1 h−1 which is much higher than that of gCN with 2D mesoporous structure, gCN from silica nanoparticle and bulk nonporous gCN. This high photocatalytic activity of gCN-KIT-6 can be attributed to 3D structure and the retarded electron-hole recombination.

中文翻译：

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具有3D连接介孔结构的石墨氮化碳的高度增强的光催化析氢活性

摘要 在本报告中，我们展示了以双氰胺为 CN 前驱体和 KIT-6 为模板，通过硬模板复制方法制备具有 3D 多孔结构的介孔石墨碳氮化物 (gCN) 及其在模拟条件下优异的光催化析氢活性。阳光。粉末 X 射线衍射、氮吸附和近边 X 射线吸收精细结构 (NEXAFS) 结果表明，制备的材料具有 gCN 晶体结构、有序介孔和 3D 多孔结构和高比表面积 (221 m2/g ）。UV-Vis 和 PL 光谱表明，介孔 gCNs 的吸收边缘轻微蓝移，PL 强度受到显着抑制。gCN-KIT-6在太阳模拟辐照下的光催化析氢活性为1。92 mmol·g-1 h-1，远高于具有二维介孔结构的gCN、来自二氧化硅纳米颗粒的gCN和块状无孔gCN。gCN-KIT-6 的这种高光催化活性可归因于 3D 结构和延迟的电子-空穴复合。