Nitrogen defect engineering in porous g-C3N4 via one-step thermal approach

Graphitic carbon nitride (g-C3N4), a smart material with fascinating properties, finds extensive use in applications such as visible-light-driven photocatalysis and lithium-ion batteries. Recently, much research has been focused on increasing the surface area of g-C3N4 by creating nitrogen defects in its structure. Here, we report a controlled one-step thermal approach for creating nitrogen defects without adding any external reducing/oxidizing agent to engineer its overall structure. Unique ion beam analysis techniques such as Rutherford backscattering spectroscopy (RBS) and elastic recoil detection analysis (ERDA) were used to investigate elemental composition and quantify hydrogen concentrations, respectively. The defect-modified g-C3N4 demonstrated an increased surface area and bandgap compared to raw g-C3N4. A maximum surface area of almost 2.35 times of the raw g-C3N4 was achieved for the sameple heated at 650 degrees C for 2 h. With the proposed one-step thermal approach, we have achieved an increase in C/N ratio, bandgap, and surface area for all defect-modified g-C3N4 samples. This study provides a simple defect engineering strategy for g-C3N4 which was verified with ion beam analysis technologies.