Hydrogen Peroxide-Treated Carbon Dot Phosphor with a Bathochromic-Shifted, Aggregation-Enhanced Emission for Light-Emitting Devices and Visible Light Communication.

It is demonstrated that treatment of blue-emissive carbon dots (CDs) with aqueous hydrogen peroxide (H2O2) results in the green emissive solid state CD phosphor with photoluminescence quantum yield of 25% and short luminescence lifetime of 6 ns. The bathochromic-shifted, enhanced green emission of H2O2-treated CDs in the powder is ascribed to surface state changes occurring in the aggregated material. Using the green emissive H2O2-treated CD phosphor, down-conversion white-light-emitting devices with cool, pure, and warm white light are fabricated. Moreover, using the green emissive CD phosphor as a color converter, a laser-based white-light source is realized, and visible light communication with a high modulation bandwidth of up to 285 MHz and data transmission rate of ≈435 Mbps is demonstrated.