Photochromism in Sm³⁺-doped inorganic semiconductor oxide CaBiNb₂O₉ induced by ultraviolet light irradiation

Semiconductor oxides are widely used in the field of optical materials due to their broad spectral response, tunable structure, low cost, high chemical and thermal stability, among other advantages. The design and fabrication of photochromic materials in semiconductor oxides have shown tremendous potential in various fields such as optoelectronic displays, optical storage, and light-stimulated responses. In this work, we have designed and fabricated a novel inorganic photochromic material by doping Sm³⁺ ions into the semiconductor oxide CaBiNb₂O₉ (CBN). The introduction of Sm³⁺ ions induces the formation of oxygen vacancies and cationic vacancies in CBN, greatly enhancing the photochromic effect of the matrix. CaBiNb₂O₉: Sm³⁺ (CBN: Sm) can achieve reversible photochromic response through 254 nm light irradiation and 350 ℃ thermal stimulation, and exhibit excellent stability and fatigue resistance. The photochromic process and performance of the CBN: Sm materials were characterized, and the potential mechanisms were analyzed and discussed. The conducted research and insights will provide support for other researchers in the design and fabrication of photochromic materials based on semiconductor oxides.