Fluorescent Material Carbon Substitution Thermal Stability

The patent uses a composite fluorescent material with chemical formula M1yM2nOzCx:M3w, combining multiple rare earth elements (M1, M3) with metal elements (M2) in a crystalline structure where carbon partially replaces oxygen. This composite structure integrates the advantages of different elements to achieve both high color rendering index (Ra≥90) and high thermal stability (bearing temperature ≥1800℃), resolving the contradiction between white light generation and reliability.

The patent optimizes the stoichiometric ratios of elements in the fluorescent material by controlling the parameters y, n, z, x, and w in the formula M1yM2nOzCx:M3w, where 0.45≤x/n≤0.75 and 0.54≤y/n≤0.6. By adjusting these compositional parameters and the partial replacement of oxygen with carbon, the material achieves improved color rendering index and thermal stability while maintaining white light emission capability.

Instead of using silicon-modified YAG, the patent employs a fundamentally different compositional approach with formula M1yM2nOzCx:M3w, incorporating rare earth elements and controlled carbon content. By adjusting the stoichiometric parameters and introducing carbon to partially replace oxygen, the material achieves bearing temperature ≥1800℃ while simultaneously achieving color rendering index Ra≥90, avoiding the eye fatigue problem caused by excessive brightness of silicon-containing materials.

The patent creates a new fluorescent material structure that copies the successful concept of elemental substitution (like silicon in YAG) but implements it differently by using carbon to partially replace oxygen in a multi-element rare earth compound, achieving superior performance in both thermal stability and color rendering without the side effects of silicon-based materials.