ABSTRACT Regulating interlayer distance is a crucial factor in the development of two-dimensional (2D) nanomaterials. A 2D metal-free photocatalyst, such as graphitic carbon nitride (g-C3N4), exhibits morphology- and microstructure-dependent photocatalytic activity. Herein, we report a straightforward and facile route for the preparation of unique lamellar g-C3N4, by co-firing melamine and ammonium chloride via microwave-assisted heating. Through the decomposition of NH4Cl, the evaporation of NH3 gas can effectively overcome van der Waals forces, expanding the interlayer distance of g-C3N4, thereby creating a lamellar structure consisting of nanosheets. Compared with bulk g-C3N4, the NH3-derived lamellar g-C3N4 exhibits a larger specific surface area and enhanced optical absorption capability, which increase photocatalytic hydrogen production because of the highly active structure, excellent utilization efficiency of photon energy, and low recombination efficiency of photogenerated charge carriers. This study provides a simple strategy for the regulation of the g-C3N4 microstructure toward highly efficient photocatalytic applications.

中文翻译：

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具有扩大层间距离的工程石墨氮化碳促进光催化析氢

摘要 调节层间距是二维 (2D) 纳米材料发展的关键因素。二维无金属光催化剂，如石墨氮化碳 (g-C3N4)，表现出依赖于形态和微结构的光催化活性。在此，我们报告了一种通过微波辅助加热共烧三聚氰胺和氯化铵来制备独特的层状 g-C3N4 的简单易行的路线。通过NH4Cl的分解，NH3气体的蒸发可以有效克服范德华力，扩大g-C3N4的层间距，从而形成由纳米片组成的层状结构。与块体 g-C3N4 相比，NH3 衍生的层状 g-C3N4 表现出更大的比表面积和增强的光吸收能力，由于其具有高活性结构、光子能量的优异利用效率和光生载流子的低复合效率，从而提高了光催化产氢量。该研究为调节 g-C3N4 微结构以实现高效光催化应用提供了一种简单的策略。