Graphitic carbon nitride (g-C₃N₄) has emerged as one of the most promising visible light active photocatalysts for NOx removal. Due to its low efficiency in bulk form though, many methods have been applied in order to improve the optical properties and photocatalytic activity. Among them, exfoliation via chemical and thermal treatment appears to be very effective and easy to perform. In this work, g-C₃N₄ was exfoliated by high-yield chemical and thermal treatment. A thorough comparative investigation was performed, revealing successful exfoliation of g-C₃N₄ and significantly enhanced visible light photocatalytic activity. Both methods led to high pore volume and specific surface area. It was established that chemical exfoliation resulted in wider band gap with more positive VB edge in comparison to thermal exfoliation. Furthermore, increased superoxide radical formation and reactivity of photogenerated electrons was demonstrated by EPR measurements in the case of chemical exfoliation. The chemically exfoliated g-C₃N₄ showed superior photocatalytic performance in NOx removal under visible light irradiation. This outcome was ascribed to the increased superoxide radical formation, the favorable band gap edges and porosity of the materials.

石墨化的氮化碳（gC ₃ N ₄）已经成为去除NOx的最有希望的可见光活性光催化剂之一。然而，由于其散装形式的低效率，已经应用了许多方法来改善光学性质和光催化活性。其中，通过化学和热处理的剥离似乎非常有效且易于执行。在这项工作中，通过高产率的化学和热处理使gC ₃ N ₄脱落。进行了彻底的比较研究，发现gC ₃ N _4的成功剥落并显着增强了可见光的光催化活性。两种方法均导致高孔体积和比表面积。已经确定，与热剥落相比，化学剥落导致更宽的带隙和更正的VB边缘。此外，在化学剥落的情况下，通过EPR测量证明了超氧化物自由基的形成和光生电子的反应性增加。化学剥落的gC ₃ N ₄在可见光照射下显示出优异的光催化性能，可去除NOx。该结果归因于超氧化物自由基形成的增加，有利的带隙边缘和材料的孔隙率。