Carbon quantum dot as well as preparation method and application thereof

The invention provides a preparation method of carbon quantum dots, which comprises the following steps: dissolving a dihydric phenol substance in a polar organic solvent, and then adding strong acid to obtain a mixed solution; carrying out solvothermal reaction on the mixed solution, wherein the reaction condition is that the reaction is carried out for 4-10 hours at the temperature of 100-200 DEG C under a closed condition; according to the method, the dihydric phenol substance is taken as the raw material, the strong acid is taken as the catalyst, and then the solvothermal reaction is carried out, so that the emission wavelength of the generated carbon quantum dots is increased, the carbon quantum dots can be located in yellow and red fluorescent regions, and in addition, the carbon quantum dots synthesized by the method have pH sensitivity and can be used for detecting the pH value. 本发明提供的一种碳量子点的制备方法，将二元酚类物质溶解于极性有机溶剂中，然后加入强酸，得到混合液；将所述混合液进行溶剂热反应，反应条件为密闭条件下于温度100～200℃下反应4～10h；上述方法中，以二元酚类物质为原料，采用强酸作为催化剂，然后进行