Crystal and Electronic Structures of g-C3N4

Abstract

The graphitic carbon nitride (g-C3N4), as a free-metal, non-toxic, earth-abundant, and environmentally friendly narrow-bandgap dimensional semiconductor with visible light response, has received extensively across-disciplines attention in the fields of photocatalysis, optoelectronic devices, biomedicines, and etc. And the unique crystal and electronic structure of g-C3N4 enables it with tunable luminescence, highly chemical stability and thermal stability. Nevertheless, the crystal and electronic structures of g-C3N4 are fundamental to understand its properties and property mechanisms and to tune performances for variable applications. This review summarizes the crystal and electronic structures of g-C3N4, along with defects identification and band structure regulations. Besides, the structure transition from small molecular precursors to macroscopic compound, including synthesis approaches and reaction conditions on structures and performances of intermediate and final products, of g-C3N4 were discussed. In addition, the applications of g-C3N4 in optoelectronics, sensors and bio-imaging, which mainly involve in photoluminescence and electroluminescence properties, were highlighted.