Laser-fabricated core-shell Ti/W based photocatalytic films with superhydrophilic self-cleaning properties

Abstract

A low-cost and efficient method for fabricating photocatalytic Ti/W-based films was developed using simple laser ablation and deposition in air. A laser marker was employed to ablate Ti/W targets separately through the glass substrate, resulting in a superhydrophilic core-shell Ti/W-based film deposited on the glass surface. The photocatalytic performance of the film was optimized by varying the laser ablation process parameters, which altered the composition of the metal core and oxide shell. Experimental results demonstrated that under 50W UV irradiation, the optimal sample decomposed 86.73 % of a methyl orange (MO) solution and 100 % of methyl stearate (MS) coated on the film surface within 50 h, restoring the film's contact angle to nearly 0°, close to its initial state. The sample also exhibited excellent photocatalytic self-cleaning properties. Furthermore, the film demonstrated high transmittance of 84 % at 550 nm and effective anti-fog properties. Notably, the sample maintained its 0° contact angle even after two months of outdoor exposure, a result not previously reported. The films also demonstrated superior photocatalysis property after 1h acid (pH=1) immersion and performance stability after 1h alkaline (pH=13) immersion. These properties highlight the broad potential of this laser deposition technique for environmental applications.