Photooxidation of IR-820 by Calixpyridinium-Induced Assembled Material and Its pH-Controlled Visual Multicolor Luminescence

Comprehensive Summary In this work, a spherical calixpyridinium–IR-820 supramolecular assembled material was fabricated based on the calixpyridinium- induced IR-820 aggregation. This assembled material exhibited a well visible light responsiveness by the photodecomposition of aggregated IR-820 accompanied by an obvious color change. Such photochromic material has many potential applications. More interestingly, the photodecomposition of aggregated IR-820 was significantly promoted, although the aggregated photosensitizers usually exhibited a lower photoreactivity. This approach can be further extended to construct various visible-light responsive supramolecular assembled materials and potentially applied in many fields. Herein, benefitting from the pH-dependent luminescent properties of calixpyridinium and the photodegradation products of IR-820, a pH-controlled visual multicolor luminescence was achieved, which was perfectly applied in the detection of pH from 5 to 10 by naked eyes.