We synthesized a new type of Eu2+/Eu3+ co-doped high-temperature high-power near-ultraviolet warm white LED glass ceramics by using high temperature solid phase method. Fluoride and oxide crystals were obtained in the amorphous glass after the heat treatment. At the same time, Eu3+ and Eu2+ entered the two crystals, respectively. To prove this phenomenon, we chose to use SEM-CL and STEM-EDX testing methods. Under 393nm near ultraviolet light excitation, the glass ceramic sample with the heat treatment at 680 degrees Celsius shows that Eu2+ ions provided broadband visible light from blue region to green region and Eu3+ ions produced a relatively strong red-light region fluorescence emission, which is located in the warm white region on the color coordinates. The sample has a relatively high fluorescence intensity and color temperature stability during the 1000-hour thermal degradation test (temperature 573K). Although under the high temperature (573K), its fluorescence intensity remains 60.6% of fluorescence intensity under the indoor temperature. This study provides references for the development and application of high-power, high-temperature, near-ultraviolet unpackaged LEDs, which has some potential practical value.
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