Novel double perovskite Sr3WO6:Sm3+, Na+ orange-red emitting phosphors with high thermal stability for white LEDs

•Sr3WO6:Sm3+ phosphors can be firstly synthesized via solid-state reaction.•The phosphor emits bright orange-red light at 407 nm excitation.•The phosphor possesses excellent thermal stability.•The w-LEDs exhibit good color rending index and low correlated color temperature.