Engineering Organic Photochromism with Photoactivated Phosphorescence: Multifunctional Smart Devices and Enhanced Four-Channel Data Storage

The development of organic photoresponsive materials with multiple responses is essential for advancing multichannel data storage systems. In this study, interactions between photochromic and phosphorescent components are engineered by covalently linking them to obtain NMC (the compound containing naphthalimide and merocyanine units), which converted into NSP (the compound containing naphthalimide and spiropyran units) upon blue light irradiation, resulting in a maximum decrease in absorption of more than 90%, a blueshift of the fluorescent emission peaks from 605 to 490 nm, and an 84 fold enhancement in phosphorescence emission intensity. These significant optical changes across the three modes upon exposure to blue light are unprecedented. The conversion of optical signals to electrical signals enables the successful implementation of devices for remote monitoring of acid gas and blue light, as well as automatic control of blue light exposure. Furthermore, the data storage capacity of the device is significantly enhanced, increasing from 1 bit to log₂(4n) bits per point in a four-channel data storage system. The design and synthesis of this compound present a promising approach for the development of sustainable, efficient, and flexible smart optoelectronic devices.