Binary Ligand‐Mediated Photochromic Tuning of Lanthanide‐Doped Upconversion Nanoparticle Conjugates. Issue 22 (19th August 2022)

• Record Type: Journal Article
• Authors: Peng, Chenxi; Chen, Xue; Suh, Yung Doug; Liu, Xiaowang
• Is Part Of: Advanced optical materials. Volume 10:Issue 22(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-08-19
• Subjects: binary ligands -- lanthanide‐doped nanoparticles -- ligand exchange -- photochromism -- upconversion; Optical materials -- Periodicals; Photonics -- Periodicals; 620.11295
• DOI: 10.1002/adom.202201354
• Languages: English
• ISSNs: 2195-1071

Abstract

Abstract: The ability to tune photochromic features of nanoparticle (NP)‐ligand conjugates can vastly extend the utility of dynamic materials in the fields of drug delivery, bioimaging, and data storage. Herein, the photochromic tuning of lanthanide‐doped upconversion nanoparticle (UCNP)‐spiropyran (SP) conjugates through a binary ligand strategy is reported. It is found that the content of SP ligand on the surface of UCNPs can be rationally controlled by an SP‐to‐oleate ligand exchange reaction, allowing for regulating the steric congestion in the ligand layer. A highly congested SP layer not only leads to an ultralong lifetime for the purple open‐ring state but also results in improved red fluorescence under UV excitation. The enhancement in steric congestion further enables increased activation energy for the ring‐opening reaction for the bound SP ligand, permitting the generation of high‐resolution self‐erasing patterns in a UCNP‐SP conjugate‐doped polydimethylsiloxane film by local irradiation with either UV or near‐infrared light. The findings provide new insights into the optical tuning of nanoconjugates by controlling the conformational dynamics of their mixed ligand layers. Abstract : The photochromic tuning of lanthanide‐doped upconversion nanoparticle (UCNP)‐spiropyran (SP) conjugates through a binary ligand strategy based on ligand congestion regulation is reported. The enhancement in steric congestion enabling increased activation energy for the ring‐opening reaction for the bound SP, permits the generation of high‐resolution self‐erasing patterns in a UCNP‐SP conjugate‐doped polydimethylsiloxane film by either UV or near‐infrared light.