To our best knowledge, we report the first long-term stable highly efficient CsPb(Br-0.4, I-0.6)(3) perovskite QDs with ethyl cellulose for warm white light generation in optoelectronic devices. Compared with conventional inorganic YAG: Ce and red phosphor, CsPb(Br-0.4, I-0.6)(3) perovskite QDs are inexpensive with outstanding characteristics of narrow FWHM of 32 nm, high luminous efficacy of 46.45 Im/W and CRI of 90.3. We propose the CsPb(Br-0.4, I-0.6)(3) perovskite QDs with ethyl cellulose as a promising red-emitting material and a color converter which can replace the conventional inorganic phosphor. (C)2016 Elsevier B.V. All rights reserved.