Graphitic carbon nitride (CN) nanosheets have aroused a great deal of interest due to their capability to utilize visible light to split water into its constituent molecules of hydrogen and oxygen (H₂ and O₂). However, the photocatalytic capacity of conventional bulk g-C₃N₄, with its large π-π conjugated electronic system, is still constrained by the π-π stacking interaction and small number of active sites. Hence, an uncomplicated post-processing method to construct a different π-π conjugated electronic system of holey CN nanosheets using alkali etching of bulk CN (CN (B)) at 300 °C for 1 h has been developed. Among such compounds, the optimal alkali treatment bulk CN (CN 3(2)) exhibits a suitable conjugated system and copious in-plane holes, and it retains the ability to absorb sunlight during alkali depolymerization. Compared to CN (B), the resultant CN 3(2) has a distensible bandgap of 2.66 eV associated with a much larger specific surface area of 265.2 m² g⁻¹. However, excessive alkali treatment significantly decrease the visible light absorbance and the photocatalytic properties of the CN nanosheet, which demonstrated that a suitable π-π conjugated electronic system is very important in allowing the process to proceed. As such, the photocatalytic H₂ and O₂ production rate of CN 3(2) was nearly 24.6 times that of CN (B) with the addition of carbon quantum dots (CQDs) and Pt.

石墨碳氮化物（CN）纳米片由于具有利用可见光将水分解成氢和氧（H ₂和O ₂）的组成分子的能力而引起了人们的极大兴趣。但是，常规本体gC ₃ N ₄的光催化能力拥有庞大的π-π共轭电子系统，仍然受到π-π堆叠相互作用和少量活性位点的限制。因此，已经开发出一种简单的后处理方法，该方法通过在300°C下对本体CN（CN（B））进行碱蚀刻1 h来构建多孔CN纳米片的不同π-π共轭电子系统。在这些化合物中，最佳的碱处理本体CN（CN 3（2））表现出合适的共轭体系和大量的面内孔，并且在碱解聚过程中保留了吸收阳光的能力。与CN（B）相比，所得的CN 3（2）具有2.66 eV的可扩展带隙，与265.2 m ²  g ^-1的更大的比表面积相关联。然而，过度的碱处理显着降低了CN纳米片的可见光吸收率和光催化性能，这表明合适的π-π共轭电子系统在允许该过程继续进行中非常重要。这样，通过添加碳量子点（CQDs）和Pt，CN 3（2）的光催化H ₂和O ₂生产率几乎是CN（B）的24.6倍。