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Two kinds of triphenylamine‐derived solid‐state emissive carbon dots (CDs) with orange and yellow color are facilely synthesized through solvothermal treatment, taking advantage of the nonplanar structure and good carrier mobility of triphenylamine unit. Theoretical calculations show that the triphenylamine structure could greatly inhibit the direct π–π stacking of aromatic skeletons and enhance the fluorescence properties of CDs in aggregation state. By adopting the CDs as single emissive layer, high‐performance orange‐color and green‐color electroluminescent light‐emitting diodes (LEDs) are successfully fabricated, with maximum brightness of 9450/4236 cd m−2, high current efficiency of 1.57/2.34 cd A−1 and low turn‐on voltage of 3.1/3.6 eV are respectively achieved. Significantly, white‐color LED device is further prepared. This work provides a universal platform for the construction of novel solid‐state emissive CDs with significant applications in photoelectric device. [ABSTRACT FROM AUTHOR]

• An oil-soluble fluorescent CDs (TPA-CDs) is synthesized through a solvent-free reaction. • Solvent-free synthesized CDs are used for both photoluminescent and electroluminescent LEDs. • A maximum luminance of 1503 cd·m−2 is achieved for TPA-CDs based electroluminescent LEDs. • Photoluminescent TPA-CDs LEDs can be easily assembled with oil soluble resin. Fluorescent carbon dots (CDs) have attracted great attention in multidisciplinary fields due to their distinctive advantages of tunable emission, low toxicity and abundant raw materials. However, it is still a big challenge to effectively applicate these CDs in electroluminescent light-emitting diodes (LEDs) due to their poor oil solubility and easy aggregation-induced quenching. Herein, an oil-soluble fluorescent CDs is designed and synthesized using triphenylamine and 4-iodophenyldiphenylamine as precursors through a solvent-free reaction. The obtained CDs (TPA-CDs) display an emission peak at 551 nm with good oil-solubility in different organic solvents. Therefore, TPA-CDs can be used as the host material of emission layer to prepare monochromatic electroluminescent LEDs with a maximum luminance of 227 cd·m−2 and as guest material in PVK to demonstrate white light electroluminescent LED with a maximum luminance of 1503 cd·m−2. This CDs can also be mixed well with oil soluble resin to easily assemble photoluminescent devices with a high luminous efficiency of 17.1 lm·W−1. This is the first example that solvent-free synthesized CDs are used for both photoluminescent and electroluminescent devices. [ABSTRACT FROM AUTHOR]