Facile Preparation of Full‐Color Tunable Room Temperature Phosphorescence Cellulose via Click Chemistry

Abstract Sustainable long‐lived room temperature phosphorescence (RTP) materials with color‐tunable afterglows are attractive but rarely reported. Here, cellulose is reconstructed by directed redox to afford ample active hydroxyl groups and water‐solubility; arylboronic acids with various π conjugations can be facilely anchored to reconstructed cellulose via click chemistry within 1 min in pure water, resulting in full‐color tunable RTP cellulose. The rigid environment provided by the B─O covalent bonds and hydrogen bonds can stabilize the triplet excitons, thus the target cellulose displays outstanding RTP performances with the lifetime of 2.67 s, phosphorescence quantum yield of 9.37%, and absolute afterglow luminance of 348 mcd m −2 . Furthermore, due to the formation of various emissive species, the smart RTP cellulose shows excitation‐ and time‐dependent afterglows. Taking advantages of sustainability, ultralong lifetime, and full‐color tunable afterglows, et al, the environmentally friendly RTP cellulose is successfully used for nontoxic afterglow inks, delay lighting, and afterglow display.