Abstract

Manganese (IV) (Mn4+)-doped fluoride phosphors generally suffer two pressing problems, thermal quenching (TQ) and poor water resistance. This study reports striking luminous intensity enhancement, anti-TQ property, and waterproofness of Mn4+-doped potassium fluosilicate phosphors induced by synergy of double coating and single passivation (coating with hydroxylated graphene quantum dots (GQDs), passivation with H2O2, and coating with K2SiF6). The luminous intensity of the phosphor is approximately 163 % of that of K2SiF6:Mn4+. The integrated emission intensity at 150 °C is 129.3 % higher than that at 30 °C. The emission intensity remains 93.2 % of the initial value after immersion in water for 480 min. These results are attributed to energy transfer from GQDs to Mn4+ and the formation of a stable Mn-free shell layer. In particular, the white light-emitting diodes produced using the phosphors maintained 99.6 % luminescence efficiency after 240 h of operation in high-temperature, high-humidity environments. We believe that this study provides a feasible approach to simultaneously enhance the thermal stability and waterproofness of Mn4+-doped fluoride phosphors.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.