AC-Driven Ultraviolet-C Electroluminescence from an All-Solution-Processed CaSiO3:Pr3+ Thin Film Based on a Metal-Oxide-Semiconductor Structure

An ultraviolet (UV) light source is continuously required for applications of sterilization as well as industrial value. In particular, research on materials and devices emitting UV-C radiation in the range from 210 to 280 nm is very meaningful and challenging work. Herein, UV-C electroluminescence (EL) from an all-solution processed CaSiO3:Pr3+ (CSO) thin film is reported for the first time. The CSO thin film is formed on a Si substrate (size of 13 x 13 mm(2)), and structurally, the UV-C EL device has a metal-oxide-semiconductor (MOS) shape consisting of CSO and interlayered SiOx of 100 and 150 nm thickness, respectively, on Si. The emission and electrical properties of the UV-C EL device are investigated under an alternating current system. The results reveal UV-C emission peaking at 276 nm attributed to the 4f5d-H-3(F)(j) transition of Pr3+ ions within CSO, with a maximum output optical power of 8.37 mu W cm(-2) (power efficiency of 0.15%) at an operating voltage of 40 V-op (50 Hz). The work can provide a feasible method for realizing large-area UV-C-emitting devices based on the MOS structure.