A strategy
to design step by step an inorganic single-doped white
phosphor is demonstrated. The method consists in tuning different
contributions of the emission by successively controlling the chemical
compositions of the solid solution or nanosegregated host matrix and
the oxidation states of the single dopant. We use this approach to
design a white phosphor Na<sub>4</sub>CaMgSc<sub>4</sub>Si<sub>10</sub>O<sub>30</sub>:Eu with excellent color rendering (CRI > 90) that
is similar to common mixed-phosphor light sources but for a single-phase.
We show that this methodology can also be extended to other phosphors
for use in diverse applications such as biomedicine or telecommunications