A phosphor-converted yellow light-emitting diodes (pc-LEDs) device has been produced by coating a low-dimensional CsCu2I3 phosphor with high quantum yield and good stability on a 310 nm ultraviolet chip. The LED device with the as-synthesized phosphor emits a pure, bright yellow color at a current of 20 mA. It shows promising exciting potential applications in photoluminescence and phototherapy fields.