A device and associated method are provided for a light emitting diode device (LED) with suppressed quantum dot (QD) photobrightening. The QD surfaces, with a maximum cross-sectional dimension of 10 nanometers, are treated with a solution including a multi-valent cation salt. In response to heating the solution, multi-valent cations become attached to the surface of the QD nanocrystals, forming treated QDs that are deposited overlying a top surface of an LED. The LED device emits a non-varying intensity of first wavelength light in the visible spectrum from the treated QDs, when subjected to a continuous exposure of a second wavelength of LED light having an intensity of greater than 50 watts per square centimeter. For example, blue, green, or red color light may be emitted when exposed to LED light in the ultraviolet (UV) spectrum, or a green or red color light when exposed to a blue color LED light.