Room temperature phosphorescent wood hydrogel
Ruixia Liu, Hongda Guo, Shouxin Liu, Jian Li, Shujun Li, Tony D. James, Zhijun Chen
Abstract
Room temperature phosphorescent (RTP) hydrogels exhibit great potential but show poor mechanical performance (Tensile strengthen <1 MPa) and non-tunable RTP performance, hindering their practical applications. Here, we develop wood hydrogel (W-hydrogel) by the in situ polymerization of acrylamide in the presence of delignified wood. As a result of the molecular interactions between the components of delignified wood and polyacrylamide, the W-hydrogel exhibit a tensile strengthen of 38.4 MPa and green RTP emission with a lifetime of 32.5 ms. Moreover, the tensile strength and RTP lifetime are increased to 153.8 MPa and 69.7 ms, upon treating W-hydrogel with ethanol. Significantly, the mechanical and RTP performance of W-hydrogel is switched by alternating “ethanol and water” treatments. Additionally, W-hydrogel is used as energy donor in order to produce red afterglow emission using RhB via an energy transfer process. Taking advantage of these properties, W-hydrogel is processed into multiple hydrogel-based luminescent materials. Hydrogels with room temperature phosphorescence have potential in a number of applications, but mechanical properties can limit the potential. Here, the authors report a wood-based hydrogel with room temperature phosphorescence, by polymerization of acrylamide with delignified wood.