Fast Photo Stimulus Responsive Ultralong Room-temperature Phosphorescence Behaviour of Benzoic Acid Derivatives @ Boric acid

Abstract Ultralong room-temperature phosphorescence (URTP) materials with photo stimulus responsive (named URTP-PSR) behavior are amazing but still rarely reported due to their great requirements on the crystal structure, complicated synthesis process, long photo-activation and deactivation time. Herein, a series of URTP-PSR materials were prepared by a facile doping process, which involved one-pot heating treatment of benzoic acid derivatives and boric acid to form an amorphous phase. The URTP-PSR materials displayed gradually enhanced ultra-long phosphorescence upon prolonged deep UV light illumination under ambient conditions to restricts the vibration and rotation of molecular. Impressively, both of the photo-activation and deactivation process can be finished within several seconds, which was much fast than previously reported URTP-PSR materials. The optical properties can be repeated many times without obvious loosing performance, suggesting excellent fatigue resistance behaviors of the URTP-PSR materials. Simultaneously, the URTP-PSR materials also displayed excellent atmosphere stability, which still maintained good optical properties even under oxygen atmosphere. Furthermore, owing to the high processability and light-stimulus emission, the URTP-PSR materials have been utilized as security ink for anti-counterfeiting pattern application. It's worth mentioning that all the raw materials are commercialized and low-cost, which could be purchased directly and benefit for the practical application. These findings break through many limitations of existing dynamic RTP materials, such as complicated preparation process, fine crystal structure, long photo-activation and deactivation time, and furthermore expand the scope of dynamic smart-response materials for great potential in many fields.