Tunable thermally enhanced lasers based on 727 nm-emitting aqueous carbon dots

Near-infrared carbon dots (NIR CDs) have been used in optoelectronics and laser devices owing to their exceptional optical properties and remarkable laser gain performance. However, achieving anti-thermal-quenching steady-state NIR emission remains a significant challenge. Herein, we synthesized high-performance, anti-thermal-quenching aqueous NIR CDs exhibiting a maximum emission wavelength of 727 nm. Detailed characterizations indicated that the rigid conjugated carbon core with high graphitic nitrogen content promoted NIR emission. The CDs exhibited high exciton binding energy and minimal structural defects, which suppressed nonradiative transitions and enabled anti-thermal-quenching optical properties. Notably, thermally enhanced laser emission was successfully achieved. The lasing threshold decreased gradually with increasing temperature, and the system maintained stable operation for 6 h without significant attenuation, thereby fully verifying its excellent optical stability and feasibility as a laser source. The results demonstrate that the anti-thermal-quenching NIR CDs have significant potential for the development of high-performance steady-state optoelectronic and laser devices.