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Multiple‐color‐emissive carbon dots (CDots) have potential applications in various fields such as bioimaging, light‐emitting devices, and photocatalysis. The majority of the current CDots to date exhibit excitation‐wavelength‐dependent emissions with their maximum emission limited at the blue‐light region. Here, a synthesis of multiple‐color‐emission CDots by controlled graphitization and surface function is reported. The CDots are synthesized through controlled thermal pyrolysis of citric acid and urea. By regulating the thermal‐pyrolysis temperature and ratio of reactants, the maximum emission of the resulting CDots gradually shifts from blue to red light, covering the entire light spectrum. Specifically, the emission position of the CDots can be tuned from 430 to 630 nm through controlling the extent of graphitization and the amount of surface functional groups, COOH. The relative photoluminescence quantum …