Designing a single-phase phosphor with high quantum efficiency
and full spectrum emission is inevitable for today’s scientific
world. Herein, an optimal strategy for realizing white emission in
a single component matrix is envisaged based on the structure–property-design-device
policy. Cationic substitution corresponding to polyhedral expansion
and contraction in A2A′B2V3O12 confirms the existence of strong and intricate linkage
in the garnet structure. The dodecahedral expansion causes compression
of VO4 tetrahedra and a blue shift. The direct correlation
of V–O bond distance with red shift validates the distortion
of the VO4 tetrahedra. The interdependence of photophysical
properties via cationic substitution and subsequent correlation of
the V–O bond distance with emission bands enabled the tailoring
of phosphor-CaSrNaMg2V3O12 with a
high quantum efficiency of 52% and excellent thermal stability of
0.39 eV. Bright warm white light-emitting diode (WLED) devices are
fabricated based on Eu3+ and Sm3+-activators.
A high quantum efficiency-74% is obtained for the designed Eu3+ phosphor. CIE coordinates near the achromatic point (0.329,
0.366), low CCT-5623 K, and high color rendering index (CRI)-87 are
obtained for the single-phase WLED device. This work puts forth a
new direction for designing and engineering promising WLEDs with enhanced
color rendering based on single-phase phosphors with full spectrum
emission.