# Photoswitching Lanthanoid Luminescence With Diazocines

## TL;DR

This paper introduces a new method to control the light emission of lanthanoid ions using diazocine photoswitches, enabling remote control and multiplexing applications.

## Contribution

A novel non-covalent strategy for photomodulating lanthanoid luminescence using diazocine photoswitches is introduced.

## Key findings

- EuIII, TbIII, and YbIII luminescence can be modulated using diazocine photoswitches without covalent bonding.
- The method allows reversible changes in luminescence intensity and lifetimes.
- Photophysical studies at 77 K provided insights into the mechanism of the effect.

## Abstract

The unique photophysical properties of the lanthanoids provide the core functionality for various high‐tech applications, including optoelectronic materials, lasers, anti‐counterfeiting dyes, or tools for biological sciences. The combination of these luminophores with photoswitches has the potential to make them remote controllable and adds new layers of complexity to their applications. We herein report that such a photomodulation of EuIII, TbIII, and YbIII luminescence is possible with the aid of diazocine photoswitches. The new approach, which does not require covalent connection of the photoswitch and antenna ligand, is by design suitable for multiplexing applications and allows for a drastic and reversible modulation of the overall luminescence intensity and luminescence lifetimes. Photophysical studies under bypassing of the antenna ligand and at 77 K gave insights into the mechanism of the effect.

Photomodulation of lanthanoid luminescence promises new layers of complexity for diverse applications. We herein present a new strategy for the manipulation of luminescence intensities and lifetimes based on diazocine photoswitches. This strategy is particularly well suited for multiplexing and does not require covalent connection of individual photoactive components.