▎ 摘　　要

Coal is the plentiful and widely and universally used fuel. However, its structural characteristic makes a perception that it is only worthwhile for generating energy via combustion. Herein we report a simple method to synthesize nanometre-sized graphene sheets with amorphous carbon addends on the edges from sub-bituminous coal. The X-ray analysis reveals the presence of crystalline carbon in the amorphous background. The average number of carbon atoms and aromatic layers was estimated as similar to 21 and 8. The interlayer spacing d(002) for the aromatic lamellae of samples leached using HF and acetic acid, are found to be 0.352 and 0.376 nm, respectively. The oxidation of coal structure resulted in nanometre sized graphene having lateral size of 4.19 nm and stacking height of 2.3 nm. The Raman spectrum analysis confirmed the formation of finite sized, less defective graphene nanolayers with leaching. The crystalline carbon within the coal matrix displaced with chemical leaching, resulting nano-meter sized graphene sheets. The results also established that with HF leaching, carbon in coal becomes more stacked and ordered compared to organic acid leached coal.