Photochromic Coordination Compound: Oxygen-Assisted Photoinduced Color Change for Triplet Oxygen Detection.

Detection of oxygen though color change is highly desirable for rapid qualitative analysis like the case of pH test papers. This work demonstrates 3O2-assisted photoinduced color change of a new photochromic coordination compound [Zn(4-aminopyridine)2Cl2] (ZnaPyCl), which represents the first photochromic compound with a selective 3O2 detection ability. The compound underwent photoinduced intraligand charge separation and formed a stable diradical-like triplet species in the solid state or in frozen solution, accompanied by conversion of triplet oxygen to singlet oxygen.

Significant enhancement of conductance of a hybrid layered molybdate semiconductor by light or heat.

Introduction of the viologen cation, a well-known electron acceptor, into molybdate layers led to a dramatic change in the conductance of the 2D hybrid material in the process of photo-induced or thermo-induced coloration, which provides an alternative approach to manipulate the electronic properties of 2D semiconductors via external optical/thermal stimuli.

Energy-dependent photochromism at room temperature for visually detecting and distinguishing X-rays.

A radiochromic material with energy-dependent X-ray-induced photochromism was obtained by incorporating a radiosensitive glycolate ligand into an electron-transfer photochromic metalloviologen system. It is highly promising for detecting soft X-rays with energies less than 2 keV and may find application in qualitatively and visually distinguishing the energy range of X-rays.