Functional carbon materials have been fabricated through simple and effective catalytic carbonization with waste coffee grounds (CGs) as carbon precursor and FeCl₃ as catalyst. The effect of FeCl₃ loading and carbonization temperature on carbon yield was investigated. The morphology and structure of as-synthesized carbons was characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and nitrogen isothermal adsorption/desorption measurement, respectively. Furthermore, the carbon materials showed high efficiency for the removal of methylene blue (MB, 653.6 mg g⁻¹), methyl orange (MO, 465.8 mg g⁻¹) and rhodamine B (RB, 366.1 mg g⁻¹). More importantly, the carbon was magnetic, so it can be easily separated by a magnet and reused multiple times. This work not only exploited a low–cost and large-scale preparation method to synthesize functional carbon materials from bioresources, but also provided an eco-friendly and effective adsorbent in water purification applications.

通过使用废咖啡渣（CGs）作为碳前驱体和FeCl ₃作为催化剂，通过简单有效的催化碳化来制造功能性碳材料。研究了FeCl _3的添加量和碳化温度对碳收率的影响。通过扫描电子显微镜（SEM），透射电子显微镜（TEM），X射线衍射（XRD），拉曼光谱，X射线光电子能谱（XPS）和氮等温吸附/解吸测量。此外，碳材料显示出高效率的亚甲基蓝（MB，653.6 mg g ^-1），甲基橙（MO，465.8 mg g ^-1）的去除。）和若丹明B（RB，366.1 mg g ^-1）。更重要的是，碳是磁性的，因此可以很容易地被磁铁分开并重复使用多次。这项工作不仅利用低成本，大规模的制备方法来从生物资源中合成功能性碳材料，而且还为净水应用提供了一种环保，有效的吸附剂。