Grain-orientation-engineered textured BaMoO4: Eu3+ luminescent thin film

Rare-earth-doped luminescent thin films have been responsible for unprecedented positive impacts in optoelectronic devices with high lateral resolution, excellent thermal stability, and strong adhesion to the solid surface. However, limited emission intensity and high-cost fabrication routine deeply inhibit their practical and commercial applications. Here, we propose a grain orientation engineering strategy via simple and low-cost polymer-assisted deposition (PAD) to fabricate textured BaMoO4: Eu3+ thin films with highly improved emission intensity by reducing the lattice mismatch between the thin films and substrates. The high-quality < 004 > textured BaMoO4: Eu3+ thin film mounted on the (001)-oriented Si substrate with the Lotgering factor F-004 of 94.6%, boosting up the emission intensity of which to 366% compared to their randomly oriented counterparts. Moreover, the as-fabricated BaMoO4: Eu3+ film shows strong red emission at 615 nm corresponding to the D-5(0) -> F-7(2) transition of Eu3+ with correlated color temperature (CCT) of 2922 degrees C and ultra-high color purity (nearly 100%). Furthermore, the geometry, size, and luminescence performance of the crystals can be precisely manipulated by tuning the growth temperature, layers of the film, and doping concentration. The present research offers a novel and low-cost route to engineer luminescent films with controllable orientation and enhanced emission intensity, which demonstrate great potentials towards practical applications and industrialization.